Dan Brown’s novel was a smash hit in 2003, even rivaling the sales of the highly popular Harry Potter series ^[1]. It spawned a number of offspring books and drew glowing reviews from the New York Times, People Magazine and the Washington Post ^[2]. It also re-ignited interest in the history of the Roman Catholic Church. As well as re-invigorating interest in the church, The Da Vinci Code has also spawned numerous “knockoffs” (as they are referred to by Publishers Weekly) ^[3], or novels that have a striking resemblance to The Da Vinci Code, including Raymond Khoury’s The Last Templar, and The Templar Legacy by Steve Berry.

It is a worldwide bestseller with more than 60.5 million copies in print (as of May 2006) and has been translated into 44 languages. It is thought to be the ninth best-selling book of all time. Combining the detective, thriller and conspiracy fiction genres, the book is the second book by Dan Brown to include the character Robert Langdon, the first being Brown’s 2000 novel Angels and Demons. In November 2004, Random House published a “Special Illustrated Edition”, with 160 illustrations interspersed with the text.

 Plot summary

This book concerns the attempts of Robert Langdon, Professor of Religious Symbology at Harvard University, to solve the murder of renowned curator Jacques Saunière (see Bérenger Saunière) of the Louvre Museum in Paris. The title of the novel refers, among other things, to the fact that Saunière’s body is found in the Denon Wing of the Louvre naked and posed like Leonardo da Vinci’s famous drawing, the Vitruvian Man, with a cryptic message written beside his body and a Pentagram drawn on his stomach in his own blood. The interpretation of hidden messages inside Leonardo’s famous works, (which relate to the concept of the Sacred feminine) including the Mona Lisa and The Last Supper, figure prominently in the solution to the mystery.

The main conflict in the novel revolves around the solution to two mysteries:

• What secret was Saunière protecting that led to his murder?

• Who is the mastermind behind his murder and the murder of the three other sénéchaux?

The novel has several concurrent storylines that follow different characters throughout different parts of the book. Eventually all the storylines and characters are brought together and resolved in its denouement.

The unraveling of the mystery requires the solution to a series of brain-teasers, including anagrams and number puzzles. The solution itself is found to be intimately connected with the possible location of the Holy Grail and to a mysterious society called the Priory of Sion, as well as to the Knights Templar. The story also involves the Catholic organization Opus Dei.

The novel is the second book of a trilogy by Brown in which Robert Langdon is the main character. The previous book, Angels and Demons, took place in Rome and concerned the Illuminati. Although Angels and Demons is centered on the same character it is not necessary to read the book in order to understand the plot of The Da Vinci Code. The next book is tentatively scheduled for release in 2007. Its working title is The Solomon Key, and it is understood to concern Freemasonry.

Characters in “The Da Vinci Code”

These are the principal characters that drive the plot of the story. It seems to be Dan Brown’s style that many have names that are puns, anagrams or hidden clues:

• Apparently, the relationship between Langdon and Vittoria Vetra from Angels and Demons has ended. This prompts the question of whether his budding romance with Sophie at this novel’s end will also have fallen by the wayside by the next novel.
• The full message Saunière wrote on the floor of the Louvre contained the line “P.S. Find Robert Langdon“. This was the reason Bezu Fache suspected Langdon of being the murderer. Fache had erased this line before Langdon arrived so that Langdon would not be aware that the police suspected him. Sophie Neveu saw the entire text of the message when it was faxed to her office by the police. Sophie realized immediately that the message was meant for her, since her grandfather used to call her “Princess Sophie” (i.e. “PS”). From this, she also knew Langdon to be innocent. She informs him of this secretly when they are in the Louvre by telling him to call her personal voicemail box and listen to the message that she had left there for him.
• At the end of the book, Robert Langdon and Sophie Neveu fall in love. They arrange to meet in Florence, the same way he did with Vittoria from Angels and Demons.

• Jacques Saunière was the Grand Master of the Priory of Sion and therefore knew the hidden location of the “keystone”, which leads to the Holy Grail and documents which would shake the foundation of Christianity and the Church. He was killed in an attempt to extract this information from him and eliminate the top members of the Priory of Sion.
• The reason that Sophie Neveu disassociated herself from her grandfather is that she discovered him participating in a pagan sex ritual (Hieros Gamos) at his home in Normandy, when she made a surprise visit there during a break from college.
• The other three lines of Saunière’s blood message are anagrams. The first line are the digits of the Fibonacci sequence out of order. The second and third lines (“O, Draconian devil!” and “Oh, lame saint!”) are anagrams respectively for “Leonardo da Vinci” and “The Mona Lisa” (in English). These clues were meant to lead to a second set of clues. On the glass over the Mona Lisa, Saunière wrote the message “So dark the con of Man” with a curator’s pen that can only be read in ultra-violet light. The second clue is an anagram for Madonna of the Rocks, another Da Vinci painting hanging nearby. Behind this painting, Saunière hid a key. On the key, written with the curator’s pen, is an address.
• The key opens a safe deposit box at the Paris branch of the Depository Bank of Zurich. Saunière’s account number at the bank is a 10-digit number that consists of the digits of the first eight Fibonacci numbers, arranged in the correct order: 1123581321.
• The instructions that Saunière revealed to Silas at gunpoint are actually a well-rehearsed lie, namely that the keystone is buried in the Church of Saint-Sulpice beneath an obelisk that lies exactly along the ancient “Rose Line” (supposedly the former Prime Meridian which passed through Paris before it was redefined to pass through Greenwich). The message beneath the obelisk simply contains a reference to a passage in the Book of Job (38:11) which reads “Hitherto shalt thou go and no further”. When Silas reads this, he realizes he has been duped.
• The keystone is actually a cryptex, a cylindrical device supposedly invented by Leonardo Da Vinci for transporting secure messages. In order to open it, the combination of rotating components must be arranged in the correct order. If forced open, an enclosed vial of vinegar will rupture and dissolve the message, which was written on papyrus. The rosewood box containing the cryptex contains clues to the combination of the cryptex, written in backwards script in the same manner as Leonardo’s journals. While fleeing to England aboard Teabing’s plane, Langdon solves the riddle and finds the combination to be “S-O-F-I-A”, the ancient (and modern) Greek form of Sophie’s name, also meaning wisdom.
  • Jacques Saunière was the Grand Master of the Priory of Sion and therefore knew the hidden location of the “keystone”, which leads to the Holy Grail and documents which would shake the foundation of Christianity and the Church. He was killed in an attempt to extract this information from him and eliminate the top members of the Priory of Sion.
  • The reason that Sophie Neveu disassociated herself from her grandfather is that she discovered him participating in a pagan sex ritual (Hieros Gamos) at his home in Normandy, when she made a surprise visit there during a break from college.
  • The other three lines of Saunière’s blood message are anagrams. The first line are the digits of the Fibonacci sequence out of order. The second and third lines (“O, Draconian devil!” and “Oh, lame saint!”) are anagrams respectively for “Leonardo da Vinci” and “The Mona Lisa” (in English). These clues were meant to lead to a second set of clues. On the glass over the Mona Lisa, Saunière wrote the message “So dark the con of Man” with a curator’s pen that can only be read in ultra-violet light. The second clue is an anagram for Madonna of the Rocks, another Da Vinci painting hanging nearby. Behind this painting, Saunière hid a key. On the key, written with the curator’s pen, is an address.
  • The key opens a safe deposit box at the Paris branch of the Depository Bank of Zurich. Saunière’s account number at the bank is a 10-digit number that consists of the digits of the first eight Fibonacci numbers, arranged in the correct order: 1123581321.
  • The instructions that Saunière revealed to Silas at gunpoint are actually a well-rehearsed lie, namely that the keystone is buried in the Church of Saint-Sulpice beneath an obelisk that lies exactly along the ancient “Rose Line” (supposedly the former Prime Meridian which passed through Paris before it was redefined to pass through Greenwich). The message beneath the obelisk simply contains a reference to a passage in the Book of Job (38:11) which reads “Hitherto shalt thou go and no further”. When Silas reads this, he realizes he has been duped.
  • The keystone is actually a cryptex, a cylindrical device supposedly invented by Leonardo Da Vinci for transporting secure messages. In order to open it, the combination of rotating components must be arranged in the correct order. If forced open, an enclosed vial of vinegar will rupture and dissolve the message, which was written on papyrus. The rosewood box containing the cryptex contains clues to the combination of the cryptex, written in backwards script in the same manner as Leonardo’s journals. While fleeing to England aboard Teabing’s plane, Langdon solves the riddle and finds the combination to be “S-O-F-I-A”, the ancient (and modern) Greek form of Sophie’s name, also meaning wisdom.

Secret of the Holy Grail

As explained by Leigh Teabing to Sophie Neveu, the figure at the right hand of Jesus is supposedly not the apostle John, but Mary Magdalene. According to the book Mary Magdalene was the wife of Jesus Christ and was in fact pregnant with his child when Jesus was crucified. The absence of a chalice in the painting supposedly indicates that Leonardo knew that Mary Magdalene was actually the Holy Grail (the bearer of Jesus’ blood). This is said to be reinforced by the letter “V” that is created with the bodily positions of Jesus and Mary, as “V” is the symbol for the sacred feminine. The apparent absence of the “Apostle John”, under this interpretation, is explained by identifying John as “the Disciple Jesus loved“, allegedly code for Mary Magdalene (see also Second Apocalypse of James). The book also notes that the color scheme of their garments are inverted: Jesus wears a red blouse with royal blue cape; John/Mary wears a royal blue blouse with red cape  — perhaps symbolizing two bonded halves of marriage.

According to the novel, the secrets of the Holy Grail, as kept by the Priory of Sion, are as follows:

• The Holy Grail is not a physical chalice, but a woman, namely Mary Magdalene, who carried the bloodline of Christ.

• The Old French expression for the Holy Grail, San gréal, actually is a play on Sang réal, which literally means “royal blood” in Old French.

• The Grail relics consist of the documents that testify to the bloodline, as well as the actual bones of Mary Magdalene.

• The Grail relics of Mary Magdalene were hidden by the Priory of Sion in a secret crypt, perhaps beneath Rosslyn Chapel.

• The Church has suppressed the truth about Mary Magdalene and the Jesus bloodline for 2000 years. This is principally because they fear the power of the sacred feminine in and of itself and because this would challenge the primacy of Saint Peter as an apostle.

• Mary Magdalene was of royal descent (through the Jewish House of Benjamin) and was the wife of Jesus, of the House of David. That she was a prostitute was slander invented by the Church to obscure their true relationship. At the time of the Crucifixion, she was pregnant. After the Crucifixion, she fled to Gaul, where she was sheltered by the Jews of Marseille. She gave birth to a daughter, named Sarah. The bloodline of Jesus and Mary Magdalene became the Merovingian dynasty of France.

• The existence of the bloodline was the secret that was contained in the documents discovered by the Crusaders after they conquered Jerusalem in 1099 (see Kingdom of Jerusalem). The Priory of Sion and the Knights Templar were organized to keep the secret.

The secrets of the Grail are connected, according to the novel, to Leonardo Da Vinci’s work as follows:

• Leonardo was a member of the Priory of Sion and knew the secret of the Grail. The secret is in fact revealed in The Last Supper, in which no actual chalice is present at the table. The figure seated next to Christ is not a man, but a woman, his wife Mary Magdalene. Most reproductions of the work are from a later alteration that obscured her obvious female characteristics.

• The androgyny of the Mona Lisa reflects the sacred union of male and female which is implied in the holy union of Jesus and Mary Magdalene. Such parity between the cosmic forces of masculine and feminine has long been a deep threat to the established power of the Church. The name Mona Lisa is actually an anagram for “Amon L’Isa”, referring to the father and mother gods of Ancient Egypt (namely Amun and Isis).

A number of different authors also speculate about the possibility of Jesus becoming a father. There are at least three children attributed to him, a daughter Tamar, born before the Crucifixion, and two sons Jesus (the Jesus Justus from the New Testament) and Josephes, both born after the Resurrection. Their names are now part of the common culture of conspiracy writers, however only two decades ago, when Holy Blood, Holy Grail was written, the names were never mentioned. The royal descents that lie at the heart of The Da Vinci Code mysteries centre on the family of Josephes, who is supposed to be the grandfather of Aminadab del Graal, first of the “Fisher Kings”. However the genealogies that are quoted in Grail lore appear to record too few generations, with children regularly being born to fathers in their 40s.

 The mystery within the mystery

Part of the advertising campaign for the novel was that the artwork in the American version of the bookjacket held various codes, and that the reader who solved them via the author’s website would be given a prize. Several thousand people actually solved the codes, and one name was randomly chosen to be the winner, with the name announced on live television, Good Morning America, in early 2004. The prize was a trip to Paris.

The five hidden puzzles reveal:

• That the back of the book jacket conceals latitude and longitude coordinates, written in reverse, light red on dark red. Adding one degree to the latitude gives the coordinates of the headquarters of the Central Intelligence Agency in Northern Virginia, which is the location of a mysterious sculpture called Kryptos. The coordinates were taken from part of the decrypted text of part 2 of the sculpture (part 4 has never been solved). When Brown has been asked why the coordinates are one degree off, his reply has been, “The discrepancy is intentional”.

• There is a secret message hidden in the text of the book flaps. The message: Is there no help for the widow’s son (a reference to Freemasonry).

• The words “only WW knows” can be seen on the back cover. This too is a reference to part 2 of the Kryptos sculpture.^[4]

• A circle with numbers, when combined with text from the book, reveals a secret message.

• There is reverse writing on the cover of the book, which is the riddle for the first cryptex.

Brown, both via his website and in person, has stated that the puzzles in the bookjacket give hints about the subject of his next novel, The Solomon Key. This repeats a theme from his earlier novels. For example, Deception Point had an encrypted message which, when solved, said, “The Da Vinci Code will surface“.

In the simplified Chinese version of The Da Vinci Code, the cover has a secret text; however, this text can be easily seen. It reads: “13-3-2-1-1-8-5 0, Draconian devil! Oh, Lame Saint! P.S. Find Robert Langdon.” This is the multiply encrypted clue written in invisible ink next to the dead body in the museum which kicks off the plot of the entire novel.

 Inspiration and influences

Direct inspiration

The novel is part of the exploration of alternative religious history. Its principal source book is listed as, as per the court case, Lynn Picknett and Clive Prince‘s The Templar Revelation, as well as the books by Margaret Starbird. Holy Blood, Holy Grail (which is explicitly named, among several others, at the beginning of chapter 60), was stated by Dan Brown not to be amongst his primary research material for the book. It has been claimed that The Da Vinci Code is a romanticised version of this work, which was itself based on a series of documentaries that ran on the BBC in the 1970s, all written and/or directed by Henry Lincoln. The main similarity includes the idea that the Merovingian kings of France were descendents from the bloodline of Jesus Christ and Mary Magdalene. In reference to Richard Leigh and Michael Baigent (two of the authors of Holy Blood, Holy Grail), Brown named the villain of his story “Leigh Teabing” (an anagram of “Baigent Leigh”). Brown confirmed this during the court case. Arguing that Lincoln has medical problems resulting in a severe limp, like the character of Leigh Teabing, Brown stated he was unaware of Lincoln’s illness and the correspondence was a coincidence. After losing before the High Court in July 12, 2006, Michael Baigent and Richard Leigh appealed to the Court of Appeal

Brown has reworked themes and characters from his own earlier novel Angels and Demons, specifically the main character, Robert Langdon.

European readers and critics noted some striking similarities between the “Da Vinci Code” and a Norwegian novel, “Sirkelens ende” (“Circle’s End”) by Tom Egeland, published in 2001 (two years before the Da Vinci code). Like the “Da Vinci Code”, “Circle’s End” involves an ancient mystery and a worldwide conspiracy, the discovery that Jesus was married to Mary Magdalene, and an albino as one of the central characters. In both novels, the main female character turns out to be the last living descendant of Christ and Mary Magdalene, and the daughter/granddaughter of the last grand master of a secret order. Many European readers have speculated that Dan Brown had plagiarized Tom Egeland’s book. Since the Norwegian novel has not been translated into English, it is generally assumed today that the similarities between the two books, although striking, are coincidental. The author himself, Tom Egeland, has in numerous interviews in European media dismissed the claim of Brown’s novel plagiarizing his own novel, stating that the similarities just show that he and Brown more or less have done the same research and found the same sources.

Indirect inspiration

Umberto Eco‘s earlier Foucault’s Pendulum also deals with conspiracies, codes, a chase around the monuments of Paris, including the Holy Blood conundrum (which is mentioned in passing) and the Knights Templar, but does so in a more critical fashion — it is in fact a satire about the futility of conspiracy theories and the people who believe them. Foucault’s Pendulum has since been dubbed “the thinking man’s The Da Vinci Code“.

Foucault’s Pendulum itself is reminiscent in plot, theme and structure to the earlier The Illuminatus! Trilogy, by Robert Shea and Robert Anton Wilson, published 13 years earlier.

Opus Dei was then cast in the role of the “evil opposition”, used to destroy the bloodline. As the bloodline has never proven to be real, but merely a theory proposed in “Holy Blood, Holy Grail”, there is no direct inspiration for this. It is believed Opus Dei’s alleged controversial past allowed Brown to weave the organisation into his novel. On a symbolic level, the Priory of Sion (male and female membership and leadership, “good”) and the Opus Dei (male-only leaders, “bad”) are at opposite sides of the scale. The latter is thus depicted as the attack dog of the Catholic Church, seeking to destroy the former and maintain the status quo. According to the novel, man needs woman for wholeness and, in fact, for experiencing the divine by means of sex (see the Hieros Gamos ritual)–for example, as the novel points out, in one’s orgasm, there is a short period of time when a person’s mind is completely empty, when one makes contact with God.

Literary significance and criticism

The book generated criticism when it was first published, due to speculations and misrepresentations of core aspects of Christianity, the history of the Roman Catholic Church, and descriptions of European art, history, and architecture. The book has received mostly negative reviews from Catholic and other Christian communities, as well as historians.

Critics accuse Brown of distorting and fabricating history. For example, Marcia Ford wrote:

Richard Abanes wrote:

The book opens with the claim by Dan Brown that “all descriptions of artwork, architecture, documents [...] and secret rituals in this novel are accurate”; but this claim is disputed by almost all academic scholars in the fields the book discusses [3].

As widely noted in the media, there has been substantial confusion among readers about whether the book is factual. Numerous works have been published that explain in detail why any claim to accuracy is difficult to substantiate, while two lawsuits have been brought alleging plagiarism in The Da Vinci Code. The second, by the authors of Holy Blood, Holy Grail claiming textual infringement of copyright, was found in Dan Brown’s favor.

Dan Brown himself dilutes the suggestion of some of the more controversial aspects being fact on his web site: “The “FACT” page makes no statement whatsoever about any of the ancient theories discussed by fictional characters. Interpreting those ideas is left to the reader.” [4]. However, it also says that “these real elements are interpreted and debated by fictional characters”, “it is my belief that some of the theories discussed by these characters may have merit.” and “the secret behind The Da Vinci Code was too well documented and significant for me to dismiss.” It is therefore entirely understandable why there would continue to be confusion as to what is the factual content of the book.

Brown’s earlier statements about the accuracy of the historical information in his book, however, were far more strident. In 2003, while promoting his novel, he was asked in interviews what parts of the history in his novel actually happened. He replied “Absolutely all of it.” In a 2003 interview with CNN’s Martin Savidge he was again asked how much of the historical background was true. He replied, “99 per cent is true … the background is all true”. Asked by Elizabeth Vargas in an ABC News special if the book would have been different if he had written it as non-fiction he replied, “I don’t think it would have.” [5] More recently Brown has avoided interviews and has been rather more circumspect about the accuracy of his claims in his few public statements. He has also, however, never retracted any of his earlier assertions that the history in the novel is accurate, despite substantial academic criticism of his claims.

In 2005, UK TV personality Tony Robinson edited and narrated a detailed rebuttal of the main arguments of Dan Brown and those of Baigent, Leigh and Lincoln, “The Real Da Vinci Code”, shown on British TV Channel 4. The program featured lengthy interviews with many of the main protagonists cited by Brown as “absolute fact” in The Da Vinci Code. Arnaud de Sede, son of Gérard de Sede, stated categorically that his father and Plantard had made up the existence of the Prieuré de Sion, the cornerstone of the Jesus bloodline theory – to quote Arnaud de Sede in the program, “frankly, it was piffle”. The program also cast severe doubt on the Roslyn association with the Grail and on other related stories like the alleged landing of Mary Magdalene in France. Detailed analysis of many other claims by Brown in The Da Vinci Code in the program showed them to be unverifiable or unhistorical.

Physical characteristics
Saturn is an oblate spheroid, i.e. it is flattened at the poles and bulging at the equator; its equatorial and polar diameters vary by almost 10% (120,536 km vs. 108,728 km). This is the result of its rapid rotation and fluid state. The other gas planets are also oblate, but to a lesser degree. Saturn is the only one of the Solar System’s planets that is less dense than water, with an average specific density of 0.69. This is a mean value; Saturn’s upper atmosphere is less dense and its core is considerably more dense than water.
Saturn’s interior is similar to Jupiter’s, having a rocky core at the center, a liquid metallic hydrogen layer above that, and a molecular hydrogen layer above that. Traces of various ices are also present. Saturn has a very hot interior, reaching 12,000 Kelvin at the core, and it radiates more energy into space than it receives from the Sun. Most of the extra energy is generated by the Kelvin-Helmholtz mechanism (slow gravitational compression), but this alone may not be sufficient to explain Saturn’s heat production. An additional proposed mechanism by which Saturn may generate some of its heat is the “raining out” of droplets of helium deep in Saturn’s interior, the droplets of helium releasing heat by friction as they fall down through the lighter hydrogen.

Saturn’s atmosphere exhibits a banded pattern similar to Jupiter’s (in fact, the nomenclature is the same), but Saturn’s bands are much fainter and are also much wider near the equator. Saturn’s winds are among the Solar System’s fastest; Voyager data indicates peak easterly winds of 500 m/s (1116 mph)[3]. Saturn’s finer cloud patterns were not observed until the Voyager flybys. Since then, however, Earth-based telescopy has improved to the point where regular observations can be made.

Saturn’s usually bland atmosphere occasionally exhibits long-lived ovals and other features common on Jupiter; in 1990 the Hubble Space Telescope observed an enormous white cloud near Saturn’s equator which was not present during the Voyager encounters and in 1994 another, smaller storm was observed. The 1990 storm was an example of a Great White Spot, a unique but short-lived Saturnian phenomenon with a roughly 30-year periodicity. Previous Great White Spots were observed in 1876, 1903, 1933, and 1960, with the 1933 storm being the most famous. The careful study of these episodes reveals interesting patterns; if it holds another storm will occur in about 2020.(Kidger 1992)

Recent images from the cassini spacecraft show that Saturn’s northern hermisphere is changing colors. It now appears a bright blue, similar to Uranus, as can be seen in the image below. This blue color cannot currently be observed from earth, because Saturn’s rings are currently blocking its northern hemiphere. One therory is that this shocking color change is a result of colder temperatures, as the shadows cast by Saturn’s rings are blocking out sunlight. This would result in the yellow clouds sinking and Saturn’s deeper blue atmosphere being revealed.

Astronomers using infrared imaging have shown that Saturn has a warm polar vortex, and is the only planet in the solar system known to do so.

An apparently permanent hexagonal wave pattern around the polar vortex in the atmosphere at about 78°N was first noted in the Voyager images[4] [5]. HST imaging of the south polar region indicates the presence of a jet stream, but no strong polar vortex nor any hexagonal standing wave
Rotational behavior
Since Saturn does not rotate on its axis at a uniform rate, two rotation periods have been assigned to it (as in Jupiter’s case): System I has a period of 10 h 14 min 00 s (844.3°/d) and encompasses the Equatorial Zone, which extends from the northern edge of the South Equatorial Belt to the southern edge of the North Equatorial Belt. All other Saturnian latitudes have been assigned a rotation period of 10 h 39 min 24 s (810.76°/d), which is System II. System III, based on radio emissions from the planet, has a period of 10 h 39 min 22.4 s (810.8°/d); because it is very close to System II, it has largely superseded it.

While approaching Saturn in 2004, the Cassini spacecraft found that the radio rotation period of Saturn had increased slightly, to approximately 10 h 45 m 45 s (± 36 s). [7] The cause of the change is unknown — however, it is thought that this is due to a movement of the radio source to a different latitude inside Saturn, with a different rotational period, rather than an actual change in Saturn’s rotation.

Planetary rings
Saturn is probably best known for its planetary rings, which make it one of the most visually remarkable objects in the solar system.

History
The rings were first observed by Galileo Galilei in 1610 with his telescope, but he was unable to identify them as such. He wrote to the Duke of Tuscany that “The planet Saturn is not alone, but is composed of three, which almost touch one another and never move nor change with respect to one another. They are arranged in a line parallel to the zodiac, and the middle one (Saturn itself) is about three times the size of the lateral ones [the edges of the rings].” He also described Saturn as having “ears.” In 1612 the plane of the rings was oriented directly at the Earth and the rings appeared to vanish, and then in 1613 they reappeared again, further confusing Galileo.

In 1655, Christiaan Huygens became the first person to suggest that Saturn was surrounded by a ring. Using a telescope that was far superior to those available to Galileo, Huygens observed Saturn and wrote that “It [Saturn] is surrounded by a thin, flat, ring, nowhere touching, inclined to the ecliptic.” [8]

In 1675, Giovanni Domenico Cassini determined that Saturn’s ring was actually composed of multiple smaller rings with gaps between them; the largest of these gaps was later named the Cassini Division.

In 1859, James Clerk Maxwell demonstrated that the rings could not be solid or they would become unstable and break apart. He proposed that the rings must be composed of numerous small particles, all independently orbiting Saturn. [9] Maxwell’s theory was proved correct in 1895 through spectroscopic studies of the rings carried out by James Keeler of Lick Observatory.

Physical characteristics
The rings can be viewed using a quite modest modern telescope or with a good pair of binoculars. They extend from 6,630 km to 120,700 km above Saturn’s equator, average close to one kilometre in thickness and are composed of silica rock, iron oxide, and ice particles ranging in size from specks of dust to the size of a small automobile. There are two main theories regarding the origin of Saturn’s rings. One theory, originally proposed by Édouard Roche in the 19th century, is that the rings were once a moon of Saturn whose orbit decayed until it came close enough to be ripped apart by tidal forces (see Roche limit). A variation of this theory is that the moon disintegrated after being struck by a large comet or asteroid. The second theory is that the rings were never part of a moon, but are instead left over from the original nebular material that Saturn formed out of. This theory is not widely accepted today, since Saturn’s rings are thought to be unstable over periods of millions of years and therefore of relatively recent origin.

While the largest gaps in the rings, such as the Cassini division and Encke division, can be seen from Earth, the Voyager spacecrafts discovered the rings to have an intricate structure of thousands of thin gaps and ringlets. This structure is thought to arise from the gravitational pull of Saturn’s many moons in several different ways. Some gaps are cleared out by the passage of tiny moonlets such as Pan, many more of which may yet be discovered, and some ringlets seem to be maintained by the gravitational effects of small shepherd satellites such as Prometheus and Pandora. Other gaps arise from resonances between the orbital period of particles in the gap and that of a more massive moon further out; Mimas maintains the Cassini division in this manner. Still more structure in the rings actually consists of spiral waves raised by the moons’ periodic gravitational perturbations.

Data from the Cassini space probe indicates that the rings of Saturn possess their own atmosphere, independent of that of the planet itself. The atmosphere is composed of molecular oxygen gas (O2) produced when ultraviolet light from the Sun disintegrates water ice in the rings. Chemical reactions between water molecule fragments and further ultraviolet stimulation create and eject, among other things O2. According to models of this atmosphere, H2 is also present. The O2 and H2 atmospheres are so sparse that if the entire atmosphere were somehow condensed onto the rings, it would be on the order of 1 atom thick. [10] The rings also have a similarly sparse OH (hydroxide) atmosphere. Like the O2, this atmosphere is produced by the disintegration of water molecules, though in this case the disintegration is done by energetic ions that bombard water molecules ejected by Saturn’s moon Enceladus. This atmosphere, despite being extremely sparse, was detected from Earth by the Hubble Space Telescope. [11]

Saturn shows complex patterns in its brightness. Most of the variability is due to the changing aspect of the rings, and this goes through two cycles every orbit. However, superimposed on this is variability due to the eccentricity of the planet’s orbit that causes the planet to display brighter oppositions in the northern hemisphere than it does in the southern. (Henshaw, C., 2003). [12]

Spokes of the rings
Until 1980, the structure of the rings of Saturn was explained exclusively as the action of gravitational forces. The Voyager spacecraft found radial features in the B ring, called spokes, which could not be explained in this manner, as their persistence and rotation around the rings were not consistent with orbital mechanics. The spokes appear dark against the lit side of the rings, and light when seen against the unlit side. It is assumed that they are connected to electromagnetic interactions, as they rotate almost synchronously with the magnetosphere of Saturn. However, the precise mechanism behind the spokes is still unknown.

Twenty-five years later, Cassini observed the spokes again. They appear to be a seasonal phenomenon, disappearing in the Saturnian midwinter/midsummer and reappearing as Saturn comes closer to equinox. The spokes were not visible when Cassini arrived at Saturn in early 2004. Some scientists speculated that the spokes would not be visible again until 2007, based on models attempting to describe spoke formation. Nevertheless, the Cassini imaging team kept looking for spokes in images of the rings, and the spokes reappeared in images taken September 5, 2005.

Natural satellites
Saturn has a large number of moons. The precise figure is uncertain as the orbiting chunks of ice in Saturn’s rings are all technically moons, and it is difficult to draw a distinction between a large ring particle and a tiny moon. Seven of the moons are massive enough to have collapsed into a spheroid under their own gravitation. These are compared to Earth’s moon in the table below. Saturn’s most noteworthy moon is Titan, the only moon in the solar system to have a dense atmosphere.
Traditionally, most of Saturn’s other moons are named after actual Titans of Greek mythology. This started because John Herschel — son of William Herschel, discoverer of Mimas and Enceladus — suggested doing so in his 1847 publication Results of Astronomical Observations made at the Cape of Good Hope,[2] because they were the sisters and brothers of Cronos (the Greek Saturn).

Exploration of Saturn

Pioneer 11 flyby
Saturn was first visited by Pioneer 11 in September 1979. It flew within 20,000 km of the planet’s cloud tops. Low-resolution images were acquired of the planet and few of its moons. Resolution was not good enough to discern surface features, however. The spacecraft also studied the rings; among the discoveries were the thin F-ring and the fact that dark gaps in the rings are bright when viewed towards the Sun, or in other words, they are not empty of material. It also measured the temperature of Titan.
Voyager flybys
In November 1980, the Voyager 1 probe visited the Saturn system. It sent back the first high-resolution images of the planet, rings, and the satellites. Surface features of various moons were seen for the first time. Voyager 1 performed a close flyby of Titan greatly increasing our knowledge of the atmosphere of the moon. However, it also proved that Titan’s atmosphere is impenetrable in visible wavelengths, so no surface details were seen. The flyby also changed the spacecraft’s trajectory out from the plane of the solar system.

Almost a year later, in August 1981, Voyager 2 continued the study of the Saturn system. More close-up images of Saturn’s moons were acquired, as well as evidence of changes in the atmosphere and the rings. Unfortunately, during the flyby, the probe’s turnable cameraplatform stuck for a couple of days and some planned imaging was lost. Saturn’s gravity was used to direct the spacecraft’s trajectory towards Uranus.

The probes discovered and confirmed several new satellites orbiting near or within the planet’s rings. They also discovered the small Maxwell and Keeler gaps.

Cassini orbiter
On July 1, 2004, the Cassini-Huygens spacecraft performed the SOI (Saturn Orbit Insertion) maneuver and entered into orbit around Saturn. Before the SOI, Cassini had already studied the system extensively. In June 2004, it had conducted a close flyby of Phoebe sending back high-resolution images and data. The orbiter completed two Titan flybys before releasing the Huygens probe on December 25, 2004. Huygens descended onto the surface of Titan on January 14, 2005, sending a flood of data during the atmospheric descent and after the landing. As of 2005, Cassini is conducting multiple flybys of Titan and icy satellites. On March 10, 2006, NASA reported that the Cassini probe found evidence of liquid water reservoirs that erupt in geysers on Saturn’s moon Enceladus [14]. On September 20, 2006, a Cassini probe photograph revealed a previously undiscovered planetary ring, outside the brighter main rings of Saturn and inside the G and E rings.[15] The primary mission ends in 2008 when the spacecraft has completed 74 orbits around the planet.

Best viewing of Saturn

Saturn has been known since prehistoric times. It is the most distant of the five planets visible to the naked eye (the other four are Mercury, Venus, Mars, and Jupiter) and was the last planet known to early astronomers until Uranus was discovered in 1781. Saturn appears to the naked eye in the night sky as a bright, yellowish star varying usually between magnitude +1 and 0 and takes approximately 29 and a half years to make a complete circuit of the ecliptic against the background constellations of the zodiac. Optical aid (a large pair of binoculars or a telescope) magnifying at least 20X is required to clearly resolve Saturn’s rings for most people.

While it is a rewarding target for observation for most of the time it is visible in the sky, Saturn and its rings are best seen when the planet is at or near opposition (the configuration of a planet when it is at an elongation of 180° and thus appears opposite the Sun in the sky.) In the opposition on January 13, 2005, Saturn appeared at its brightest until 2031, mostly due to a favorable orientation of the rings relative to the Earth.

Saturn in various cultures
Saturn is known as “Sani” or “Shani” in Hindu Astrology. Hindus believe in the existence of Nine Planets – known as Navagraha(s). These Navagrahas were propitiated as planetary influences govern the life of individuals. Sani is identified as an inauspicious planet, and is worshipped by individuals going through a “bad” phase in their life. Sani’s father is the Sun God “Surya”.

Chinese and Japanese culture designate the planet Saturn as the earth star (土星). This is based on Five Elements which was traditionally used to classify natural elements.

In Hebrew, Saturn is called ‘Shabbathai’. Its Angel is Cassiel. Its Intelligence, or beneficial spirit, is Agiel (layga), and its spirit (darker aspect) is Zazel (lzaz). See: Kabbalah.

In Bahasa Malaysia (the Malay language), its name is ‘Zuhal’.

JULY 14, 1930 ON THE NATURE OF REALITY

Near Potsdam is a small place called Caputh. There, upon a hill, stands a brown wooden house with a red tile roof. Round about, like sentinels, stand the slim trunks of pine trees. In the wooden villa dwells the mathematician, Albert Einstein.

At about 4 o’clock one recent afternoon Rabindranath Tagore walked along the sandy path to the house. he wore a suit of soft, blue cloth; he leaned a bit forward as he walked and one hand was bent behind his back. Beside him stood sturdy, erect Einstein …

TAGORE: You have been busy, hunting down with mathematics, the two ancient entities, time and space, while I have been lecturing in this country on the eternal world of man, the universe of reality.

EINSTEIN: Do you believe in the divine isolated from the world?

TAGORE: Not isolated. The infinite personality of man comprehends the universe. There cannot be anything that cannot be subsumed by the human personality, and this proves that the truth of the universe is human truth.

EINSTEIN: There are two different conceptions about the nature of the universe – the world as a unity dependent on humanity, and the world as reality independent of the human factor.

TAGORE: When our universe is in harmony with man, the eternal, we know it as truth, we feel it as beauty.

EINSTEIN: This is a purely human conception of the universe.

TAGORE: ThE world is a human world – the scientific view of it is also that of the scientific man. Therefore, the world apart from us does not exist; it is a relative world, depending for its reality upon our consciousness. There is some standard of reason and enjoyment which gives it truth, the standard of the eternal man whose experiences are made possible through our experiences.

EINSTEIN: This is a realization of the human entity.

TAGORE: Yes, one eternal entity. We have to realize it through our emotions and activities. We realize the supreme man, who has no individuaL limitations, through our limitations.

Science is concerned with that which is not confined to individuals; it is the impersonal human world of truths. Religion realizes these truths and links them up with our deeper needs. Our individual consciousness of truth gains universal significance. Religion applies values to truth, and we know truth as good through own harmony with it.

EINSTEIN Truth, then, or beauty, is not independent of man?

TAGORE: No, I do not say so.

EINSTEIN: If there were no human beings any more, the Apollo Belvedere no longer would be beautiful?

TAGORE: No!

EINSTEIN: I agree with this conception of beauty, but not with regard to truth.

TAGORE Why not? Truth is realized through men.

EINSTEIN I cannot prove my conception is right, but that is my religion.

TAGORE Beauty is in the ideal of perfect harmony, which is in the universal being; truth is the perfect comprehension of the universal mind. We individuals approach it through our own mistakes and blunders, through our accumulated experience, through our illumined consciousness. How otherwise can we know truth?

EINSTEIN: I cannot prove, but I believe in the Pythagorean argument, that the truth is independent of human beings. It is the problem of the logic of continuity.

TAGORE : Truth, which is one with the universal being, must be essentially human; otherwise, whatever we individuals realize as true, never can be called truth. At least, the truth which is described as scientific and which only can be reached through the process of logic – —in other words, by an organ of thought which is human. According to the Indian philosophy there is Brahman, the absolute truth, which cannot be conceived by the isolation of the individual mind or described by words, but can be realized only by merging the individual in its infinity. But such a truth cannot belong to science. The nature of truth which we are discussing is an appearance; that is to say, what appears to be true to the human mind, and therefore is human, and may be called maya, or illusion.

EINSTEIN It is no illusion of the individual, but of the species.

TAGORE: The species also belongs to a unity, to humanity. Therefore the entire human mind realizes truth; the Indian and the European mind meet in a common realization.

***

EINSTEIN: The word species is used in German for all human beings; as a matter of fact, even the apes and the frogs would belong to it. The problem is whether truth is independent of our consciousness.

TAGORE: What we call truth lies in the rational harmony between the subjective and objective aspects of reality, both of which belong to the superpersonal man.

EINSTEIN: We do things with our mind, even in our everyday life, for which we are not responsible. The mind acknowledges realities outside of it, independent of it. For instance, nobody may be in this house, yet that table remains where it is.

TAGORE: Yes, it remains outside the individual mind, but not the universal mind. The table is that which is perceptible by some kind of consciousness we possess.

EINSTEIN: If nobody were in the house the table would exist all the same, but this is already illegitimate from your point of view, because we cannot explain what it means, that the table is there, independently of us. Our natural point of view in regard to the existence of truth apart from humanity cannot be explained or proved, but it is a belief which nobody can lack – —not even primitive beings. We attribute to truth a superhuman objectivity. It is indispensable for us – —this reality which is independent of our existence and our experience and our mind – though we cannot say what it means.

TAGORE: In any case, if there be any truth absolutely unrelated to humanity, then for us it is absolutely non-existing.

EINSTEIN: Then I am more religious than you are!

TAGORE: My religion is in the reconciliation of the superpersonal man, the universal spirit, in my own individual being.

2nd Law:- A Planet sweeps equal areas in equal times.

3rd Law:- A precise connection between the size of a planet’s orbit & the period for it 2 go once around the Sun. It clearly applies 2 Uranus, Neptune and Pluto, planets discovered long after the death of Kepler.

The third law states square of the periods of the planets (the imes for them 2 complete 1 orbit) r proportional2 the cubes of their averagedistance from the Sun; the more distant the planet, the slower it moves. But according to the precise mathemetical law: P^2=A^3, where P represents the period of one revolutionof the planet, and A is the distance from the Sun measured in “Astronomical Units”

* P.O. Box, 5231, Glendale, CA 91221
^ Professor Emeritus of Psychology, State University of New York at Oswego
` 448 NE Ravenna Blvd., #106, Seattle, WA 98115-6401
# Professor of Physics and Astronomy, University of Hawaii

History
The German physician Samuel Hahnemann (1755-1843) is generally acknowledged to be the founder and developer of homeopathy, although some of his concepts appear very early in medical history.1 Dissatisfied with the state of medicine at the time, which included bleeding, purging, cupping and excessive doses of mercury, he ceased his medical practice in 1782 and began translating medical and chemical texts. It was during this time that he apparently began to seriously question the proposed mechanisms of drug activity of his contemporaries.

Hahnemann followed a tradition that viewed disease as a matter of the vital force or spirit. The concept of the vital spirit appears to be one of the earliest speculations in recorded medical history and similar forces form the proposed basis for any number of metaphysical health practices. It is an alleged nonmaterial “force” that sustains life and for which there is no objective evidence.2 According to Hahnemann, “The causes of our maladies cannot be material, since the least foreign material substance, however mild it may appear to us, if introduced into our blood-vessels, is promptly ejected by the vital force, as though it were a poison….no disease, in a word, is caused by any material substance, but that every one is only and always a peculiar, virtual, dynamic derangement of the health.”3

Consistent with this philosophy is the belief that it is more important to pay attention to symptoms than to the external causes of disease. Knowing the specific symptoms of illness, treatment is then a matter of finding a substance or substances that induced the same symptoms in a healthy individual. This is the basis of Hahnemann’s “Principle of Similars.” The work of Pasteur and Koch on inoculations with very small amounts of weakened disease-causing microbes seemed to support this notion at the time.

Hahnemann and his followers went on to test the effects of almost 100 substances on themselves, a process known as “proving.” The typical procedure was for a healthy person to ingest a small amount of a particular substance and then attempt to carefully note any reaction or symptom (including emotional or mental reactions) that occurred. By this method, Hahnemann and his followers “proved” that the substance was an effective remedy for a particular symptom. That such a method of determining the effectiveness of a treatment is implausible and at least open to the power of suggestion should be inarguable. In fact, in one controlled study, healthy subjects reported similar symptoms whether given a homeopathic dilution of belladonna or a placebo.4

Nevertheless, the collected experiences of such incidents became the basis for a compendium called the Materia Medica. Because some of the substances tested were toxic (such as poison ivy, strychnine and various snake venoms), during a proving it made sense to ingest minuscule doses. This may be the source or the homeopathic principle of “infinitesimal dilutions” in which the most dilute solutions are alleged to be the most potent.

The origin of the principle of “potentization” is more obscure. Potentization purports to make the diluted, inert substance active by releasing its energy. According to Hahnemann: “Homeopathic potentizations are processes by which the medicinal properties of drugs, which are in a latent state in the crude substance, are excited and enabled to act spiritually upon the vital forces.”5 Simple dilution of a drug is insufficient to produce a cure. To achieve potentization, after each successive 1-to-9 (“D”) or 1-to-100 (“C”) dilution, the solution must be shaken vigorously (the process is known as “succussion”). In the case of a powdered substance, it must be vigorously ground up (trituration). Potentization purports to liberate the energy of the substance being used for treatment and this liberated energy purportedly remains, even in the lowest doses.

Hahnemann believed that homeopathic remedies must be appropriately prescribed for individual body types and personalities, based on the ancient humoral theories of Galen. According to these theories, there were four body types and personalities, based on which body “humor” predominated: blood (sanguine, warm-hearted and volatile), black bile (melancholic, sad), yellow bile (choleric, quick to anger and to action) and phlegm (phlegmatic, sluggish and apathetic). In addition to describing a few basic body types, he also suggested that there are a corresponding few primary causes of acute and chronic illnesses, which he called “miasms.” The first miasm, known as “psora” (itch) refers to a general susceptibility to disease and may be considered the source of all chronic diseases. The other two miasms in homeopathic theory are the venereal diseases syphilis and sycosis (gonorrhea). Together, these three conditions were considered to be the cause of at least 80 per cent of all chronic diseases.

Homeopathy has made several important indirect contributions to the practice of medicine. At the time that it was developed, the medical treatments of the time were often more dangerous than the disease that they purported to treat. Indeed, homeopathy may have helped hasten the demise of such treatments. Homeopathy provided the initial idea and source for useful drugs such as nitroglycerin6 and aconite.7 Early scientists such as Joseph Lister and Sidney Ringer stated that they were led to important pharmacological discoveries because of homeopathy.8 Homeopathy has also been given credit for providing early support for clinical trials with control groups, systematic and quantitative procedures and the use of statistics in medicine.9

From the standpoint of veterinary medicine, it is curious that Hahnemann did none of his work on animals. Psora, syphilis and gonorrhea are not conditions recognized in animals. The fallacy of prescribing medications for animals based on how they make people feel seems obvious given interspecies variations between reactions to various pharmacologic substances. The concepts of prescribing medications for body types and personalities would seem to be particularly difficult to apply to animals, as well.

It should be obvious that the premises upon which Hahnemann’s work were based are difficult to support based on current knowledge. From a strictly hypothetical standpoint it is possible that Hahnemann came up with the right conclusion from the wrong reasons. However, while criticisms based solely on the origin of the philosophy may not be entirely damning, they are, at least, instructive.

The Physics of Homeopathy
If homeopathic remedies are effective, there is a mechanism by which they work. It is a fact that the mechanism of action by which they might work has not been established. If the remedies do work, they must do so in a manner which would appear to violate established principles of physics, chemistry and pharmacology or they must work in a manner which is yet to be discovered. As one early critic of homeopathy wrote, “Either Hahnemann is right, in which case our science and the basis of our thinking is nonsense, or he is wrong, in which case this teaching is nonsense.”10

By successively diluting the initial substance, extremely dilute solutions can be made rather quickly. The dilution limit is reached when the volume of the solute is unlikely to contain a single molecule of the solvent. The limit recognizes that there is a large but finite and specific number of atoms or molecules in a mole of substance (a mole is the molecular weight of a substance, expressed in grams). That number of atoms or molecules is 6.022 X 1023, also known as Avogadro’s number.

Homeopathic remedies are diluted by either a factor of 10 or 100. “D” dilutions are prepared by serial dilutions of 1:10; “C” dilutions are prepared by serial dilutions of 1:100. Thus, a remedy marked C30 would imply a 1:100 dilution performed 30 times. By simple mathematics, it can be calculated that at dilutions of C12 or D24 or greater, it is not likely that the remedies contain even a single molecule of the original substance.

Since the original substance is not present in extremely dilute homeopathic remedies, explanations for a mechanism of action of homeopathic medications have moved towards speculation. Such proposals include the formation of stable ice crystals, magnetic properties of water or the formation of protein shells in the water mixture.11 Water molecules are highly polarized, a fact that already accounts for much of the special role of water in biology. However, the likelihood that water can maintain a complex ice-like structure under the vigorous shaking that usually accompanies homeopathic preparation has not been demonstrated. Neither has any physical mechanism by which such hypothetical structures can produce the implied biological effects.

Some of the hypotheses appear to be completely insupportable. Speculation that the mechanism of action of homeopathic medications is somehow related to biological magnetite have been criticized by the investigator who discovered the substance as lacking any foundation and based on a misunderstanding the structure of magnetite.12 Water is also not ferromagnetic.

Structural changes in matter appear to be easily demonstrable in other applications, using such techniques as transmission electron microscopy, spectroscopy, ultraviolet transmission characteristics, X-rays and ultrasound. If they exist, structural changes in the composition of homeopathic remedies should be relatively easy to detect. So far, such changes have not been demonstrated. One ultrasonographic study failed to show differences between homeopathic remedies and water.13 On an empirical basis, even a homeopathic practitioner and his patients were unable to distinguish between two different homeopathic remedies with “strikingly different properties” over nine years of testing.14

From a physical standpoint, structural changes in the water of extremely dilute solutions seem unlikely. Structural studies of water/alcohol mixtures will show regions of local order. However, these regions are transient; depending on the temperature, they can only last for the briefest of times. For most materials, local order does not persist in the liquid phase (the problem is entropy).15. The exceptions are liquid crystals, whose highly elongated molecules are still not able to move about freely when the liquid phase is reached. There has never been the slightest hint, from theory or experiment, that water can form a liquid crystal.

It may also be postulated that there is some sort of biologic effect of homeopathic medications that is independent of known physical laws. Of course, such speculation would be virtually impossible to test and there is no known substance which fits such parameters. Appealing to unknown laws to explain undocumented phenomena simply falls outside the framework of legitimate science.

Further physical difficulties with the concept of homeopathic dilutions relate to the fact that many such remedies come in the form of lactose tablets. In these instances, the homeopathic dilution is applied to the pill, which serves as a carrier. Of course, the diluted liquid must evaporate, which leads to the question of how the information is transferred from liquid to lactose tablet. Other questions include why the diluted mixture would remember only the healing powers of the active substance but forget the side-effects or why the water doesn’t remember other things with which it might have been in contact.

The fact that there is no known mechanism by which extremely dilute homeopathic medications should be able to exert a biological effect is indeed a source or concern to proponents of homeopathy. In fact, if proposed mechanisms can be shown to be insupportable, the Director of the Office of Alternative Medicine of the National Institutes of Health has written that, “highly speculative and imaginary [sic] explanations may be necessary.”16 As a Nobel Prize winning physicist noted, “The theory of quantum electrodynamics describes Nature as absurd from the point of view of common sense. And it agrees fully with experiment.”17 From a mechanistic point of view, however, homeopathy neither makes sense nor agrees with any experiment. Accordingly, most discussions of the possible effects of homeopathy prefer to focus on discussions of results of studies.

In Vitro Studies
In 1988, homeopathy was thrust into the forefront of controversy with the first publication of work supporting effects of homeopathic solutions in a mainstream science journal. The authors of the paper suggested that extremely dilute solutions of antiserum against human IgE were able to induce basophil degranulation.18 Although the experimental model chosen is known to be extremely unstable, the journal in which the study was published could find no apparent flaws. Subsequent to publication, however, the journal sent an investigating team to the laboratory which concluded that there were serious flaws in the original investigation.19 That a war of words subsequently commenced is inarguable. More to the point is that at least three separate investigators using identical or similar experimental models have failed to reproduce the results.20, 21, 22

In fact, the only studies which indicate an in vitro effect of homeopathic dilutions come from the same laboratory. The lead investigator of the studies has since gone on to claim that homeopathic information has been digitized and can be transferred by computer disk over the Internet. Furthermore, his immunopharmacology laboratory has been shut down by INSERM, the French medical research agency.23 Finally, a libel claim by the investigator against two French Nobel prize winners who called the investigator a fraud was recently thrown out of French courts.24

Reviews and Meta-Analyses
When trying to evaluate the evidence for the effectiveness of homeopathic remedies, it is possible to find investigations in which positive, negative or no results are reported. Evaluation of the literature for any form of therapy is difficult and studies vary as to quality. Such a problem appears to be particularly acute in the evaluation of literature concerning alternative therapies such as homeopathy. For example, investigators in one study categorized all 204 articles in one year’s editions of four journals on alternative medicine as positive, neutral or negative. They found 64 per cent of the papers were classified as helpful, 35 per cent as neutral and only 1 per cent as negative. The investigators concluded that there is a strong publication bias in favor of positive conclusions about alternative therapies and that their findings imply that the literature is not objective.25

One way to attempt to answer the question of the effectiveness of homeopathic medications is to look at reviews and meta-analyses (studies of studies). Of course, whether by review or by meta-analysis, attempts at reviewing any medical literature are not without their own problems. Reviews have been criticized as being subject to the bias of the reviewer. On the other hand, meta-analyses, which attempt to gather information and draw conclusions by pooling various reports have been much criticized for using many “weak” studies to arrive at a “strong” conclusion and for relying on the subjective opinions of the authors to determine which studies are worthy of inclusion, among other reasons.26 Further concern about the validity of meta-analysis comes from recent work which indicates disagreement between meta-analysis and subsequent large, randomized, controlled clinical trials in as many as 35 per cent of the cases studied.27

Nevertheless, several reviews and meta-analyses on homeopathy have been performed. Apparently, their results are open to some interpretation. That interpretation may, at first glance, seem to be no more than a “glass half-empty or half-full” argument between proponents of homeopathy and those of evidence-based medicine. Thus, for the purposes of review, it seems most useful to quote the conclusions of the studies rather than take individual bits of data out of them. The authors were able to find four meta-analyses and six reviews of the effects of homeopathic medications. Three of the reviews specifically relate to veterinary medicine.

In 1985, a chapter on veterinary homeopathy concluded that, “Contrary to what you hear or read too often, rigorous scientific demonstration of the therapeutic effect of homeopathic remedies in veterinary medicine has not yet been done. Although it may seem exaggerated to conclude that homeopathy has absolutely no place, from a pragmatic point of view (and relative among animal owners…), in veterinary medicine, it is obvious that future works will have to bend to the new modern methodologies in order to be able to take away the firm beliefs of stern minds.”28

A 1990 review of 40 published randomized trials of homeopathy in human medicine found that most of the studies had major methodological flaws and concluded that, “the results do not provide acceptable evidence that homeopathic treatments are effective.”29

A 1991 meta-analysis of homeopathy in human medicine concluded, “At the moment the evidence of clinical trials is positive but not sufficient to draw definitive conclusions because most trials are of low methodological quality and because of the unknown role of publication bias. This indicates that there is a legitimate case for further evaluation of homeopathy, but only by means of well performed trials.” The investigators also noted that, “Critical people who do not believe in the efficacy of homeopathy before reading the evidence presented here probably will still not be convinced; people who were more ambivalent in advance will perhaps have a more optimistic view now, whereas people who already believed in the efficacy of homeopathy might at this moment be almost certain that homeopathy works.”30 In a later letter, the authors noted that, “The results of our review would probably be interpreted differently if laboratory studies showed convincing evidence that there is some action of high potencies.”31

A 1992 German review of homeopathy concluded that, “Due to the advance of alternative medicine a critical synopsis by means of the comparison between scientific medicine (clinical medicine) and homeopathy is warranted. The review of studies carried out according to current scientific criteria revealed – at best – a placebo effect of homeopathy. Until now there is no proven mechanism for the mode of action of homeopathy. Sometimes so-called “alternative medicine” prevents effective curative measures. In spite of the justified criticism concerning the technical over-estimation of classical medicine, scientific research should remain the basis of clinical work.”32

A 1993 German review of homeopathy in veterinary medicine makes several conclusions:

* “Doctor and veterinarian are similarly obligated to apply the therapeutic measure that prevailing opinions deem most effective. Where there is for particular definite illnesses a particularly effective and generally recognized treatment, in such cases the supporters of homeopathy may not disregard the better successes from their own differing direction.”

* It is undisputed that homeopathy in the area of stronger potency can achieve effects pharmacologically and toxicologically; the superiority of homeopathy as a therapeutic measure in comparison with conventional therapy methods is at this point not verified. Moreover, the harmlessness of homeopathy in stronger potency is for the most part not verified.

* The effectiveness of homeopathy in middle and high potencies is up to now not verified. It is undisputed that with the help of homeopathy, not insignificant placebo effects can be achieved. In veterinary medicine, giving an animal an ‘active’ placebo and another a ‘passive’ can play a significant role and influence the owner.”33

A 1994 review and meta-analysis of serial agitated dilutions (SAD) in experimental toxicology stated that, “As with clinical studies, the overall quality of toxicology research using SAD preparations is low. The majority of studies either could not be reevaluated by the reviewers or were of such low quality that their likelihood of validity is doubtful. The number of methodologically sound, independently reproduced studies is too small to make any definitive conclusions regarding the effect of SAD preparations in toxicology.”34

A 1996 review of homeopathy, concluded that:

* “No one should ignore the role of non-specific factors in therapeutic efficacy, such as the natural history of a given disease and the placebo effect. Indeed, these factors can be used to therapeutic advantage.”

* “As homeopathic treatments are generally used in conditions with variable outcome or showing spontaneous recovery (hence their placebo responsiveness), these treatments are widely considered to have an effect in some patients.”

* “However, despite the large number of comparative trials carried out to date there is no evidence that homeopathy is any more effective than placebo therapy given in identical conditions.”

* “We believe that homeopathic preparations should not be used to treat serious diseases when other drugs are known to be both effective and safe.”

* “Pending further evidence, homeopathy remains a form of placebo therapy.”35

A 1997 meta-analysis concluded, “The results of our meta-analysis are not compatible with the hypothesis that the clinical effects of homeopathy are completely due to placebo. However, we found insufficient evidence from these studies that homeopathy is clearly efficacious for any single clinical condition.” Furthermore, “Our study has no major implications for clinical practice because we found little evidence of effectiveness of any single homeopathic approach on any single clinical condition.” The authors concluded by calling for more research, “providing it is rigorous and systematic.”36 One critic of the study cautioned that when the best trials were examined, the odds of a positive effect of the therapy were distinctly lower than in the overall study.37 Another critic suggested further caution in interpreting the results of this study by noting that negative trials may have been less likely to be published, which may have skewed the analysis. 38

Another meta-analysis conducted in 1997 examined the use of homeopathy for the treatment of postoperative ileus, measured by the time to first flatus. The investigators concluded that their analyses “do not provide evidence for the use of a particular homeopathic remedy or for a combination of remedies for postoperative ileus. Several drawbacks inherent in the original studies and in the methodology of meta-analysis preclude a firm conclusion.” Given those caveats, the study also suggested that homeopathic dilutions less than 12C (those which may contain some of the original substance) had a significant effect, whereas dilutions greater than 12C had none.39

A 1998 review of homeopathic treatment in animals suggested approaching homeopathy with an “open mind.” As evidence for the effectiveness of homeopathic treatment in animals, the study cites 3 studies in which some clinical evidence of effectiveness was seen, 7 in which the results were difficult to interpret for various reasons and 6 in which there was no response to treatment or worsening of the condition. Several of the studies cited were performed on healthy animals. In one of the studies in which the condition of sick animals worsened, the worsening of the animal’s health is taken as possible evidence of treatment effectiveness, according to “Herring’s Law.”13 Critics would note that such a “law” or “healing crisis” would mean that one can’t lose when administering homeopathic medications because whether the patient improves or gets worse, the treatment may be viewed as being successful.

Very few, if any, of the researchers conducting animal and in vitro studies on homeopathy have been rigorously conducted. Properly blinded, randomized experiments with high dilution homeopathic preparations and both a placebo group and a known effective treatment group with a large number of animals and predefined outcome variables that examine the effect on diseases (rather than production efficiency) are absent in veterinary homeopathy. In addition, researchers have been guilty of not reporting differences (if such existed) between the homeopath and placebo groups.33 While the animals (and tissue preparations) may not be susceptible to suggestibility, clearly the researcher making the critical observations could be influenced. One would hope that animals researchers would also be aware of the pioneering work of Pavlov showing that animals are often responding to any change in their environment which could obviously be confused with a response to homeopathic medication.40

Subsequent to submission of the most recent meta-analysis in human medicine, several good trials of homeopathic medications have been conducted in human medicine. Randomized, placebo-controlled double blind studies have shown homeopathic remedies to be ineffective in the treatment of adenoid vegetations in children,41 for control of pain and infection after total abdominal hysterectomy42 and for prophylaxis of migraine headache.43, 44 Furthermore, to date, no single study of homeopathy showing positive results has been successfully replicated.

Curiously, the lack of good evidence of effectiveness of homeopathic remedies may be irrelevant to supporters of homeopathy. One leading advocate asserts that proving the effectiveness of homeopathy through scientific research is not important and suggests that personal experience is more important that any number of carefully controlled studies.45 Positive expectations and beliefs of patients and healers have historically resulted in reports of excellent or good outcomes in more than 70 per cent of cases even though the treatments given are now known to have been worthless.46

Is homeopathy safe?
Safety is, of course, vital to the discussion of any form of therapy. In fact, most conclusions are that homeopathic remedies are largely safe. Such a finding would, of course, not be unexpected were the remedy to contain only a water and/or alcohol solvent (that is, that the solution would contain none of the original substance).

However, while infrequent, there are reports of adverse reactions to homeopathic medications. Adverse reactions have been reported ranging from pruritis and a measles-like skin rash to anaphylactic shock,47 from pancreatitis48 to contact dermatitis.49 In regards to the safety of homeopathic remedies, the previously cited 1996 review stated that, “Serious adverse effects have been reported with low dilutions (<4CH>5CH) administered orally or sublingually appear to be entirely safe. We believe that homeopathic preparations should not be used to treat serious diseases when other drugs are known to be both effective and safe. In addition, regardless of the condition treated, dilution below 5CH (e.g. 3 or 4CH and especially decimal dilutions or mother tinctures) must not only be considered as having no proven efficacy but also as having potential dangers.”33

Further concerns as to safety arise from the apparent attitude against immunization by practitioners of homeopathic therapy. In human medicine, several surveys have demonstrated that homeopathic practitioners routinely advise their clients against immunization.50, 51, 52, 53 Such an attitude would appear to be completely insupportable in light of the tremendous advances made in the protection from disease that vaccination clearly and reliably affords. The origin of homeopathic antipathy to vaccination is unknown; there is nothing in Hahnemann’s writings against immunization.54 It may arise from a general hostility towards modern medicine that, according to studies, appears to be prevalent within complementary medicine in general.55, 56

Homeopathic practitioners may also employ the use of “homeopathic vaccines” or “nosodes” prepared from high dilutions of infectious agents, material such as vomitus, discharges or fecal matter or infected tissues. Curiously, nosodes are not prepared according to homeopathic principles, rather, they would be more properly described as being isopathy. Hahnemann himself decried the use of such preparations. 57 There is no evidence at all to suggest that such “immunizations” have any effectiveness.58 There is one case reported in the human literature where a patient followed her homeopath’s advice and took a homeopathic immunization against malaria before traveling to an endemic area. The patient promptly got malaria.59 Homeopathic nosodes have failed to protect dogs from death due to parvoviral enteritis.60 Even given the concerns regarding potential problems with immunization in animals, it is virtually inconceivable that an ethical medical practitioner would recommend against the use of proven effective vaccine prophylaxis for diseases such as rabies, parvoviral enteritis or viral encephalitis (to name a few). Vaccination arguably constitutes the single most successful public health measure in human history.

Ethics
Any discussion of homeopathy also entails consideration of ethical issues. As homeopathy is unquestionably unproven, it seems clearly unethical to merely give the therapy to an animal and its trusting owner and wait and see what happens.61 Furthermore, social morality would demand that the client be fully informed of the experimental nature of the therapy and consent to it before it is provided. It would also seem clearly unethical to employ an unproven therapy such as homeopathy in cases where an acceptable and effective treatment already exists or where the patient is at risk for greater suffering if the unproven therapy fails.62 Further ethical considerations require that proof of effectiveness be established if safety and efficacy questions have not been documented, as is the case with homeopathy. It would also seem reasonable to expect that if a professional community intends to employ an unproven remedy, said community has the ethical obligation to engage in proper clinical research to help establish or disprove the effectiveness of that remedy.63

Discussion
It is difficult to precisely determine what homeopathy is today. Homeopathy as a single, unified school of thought simply does not exist.64 One report has noted that, “There are as many homeopathies as there are homeopaths.65 Furthermore, the ready availability of mass-marketed, non-prescription homeopathic remedies would appear to violate Hahnemann’s principle of individualizing therapy based on the symptoms of each patient.56 Additionally, the mere fact that homeopathy is a treatment philosophy based exclusively on the recognition and treatment of symptoms would seem to contradict claims made by advocates that homeopathy treats the whole patient, whereas “traditional” medicine is merely treats the symptoms of disease.1

It is interesting to compare the course of progress between medications such as aspirin and homeopathy. It was known for many hundreds of years that chewing on willow bark helped relieve pain and inflammation. The active component of aspirin, initially called salicin, was isolated in 1823, not long after the advent of homeopathy. In 1899, a derivative of salicin, acetylsalicylic acid, was developed and marketed for the first time. The mechanism of action of aspirin began to be uncovered about fifty years later. From this basic information, a proliferation of useful non-steroidal anti-inflammatory drugs developed, leading to the most recent advancements of so-called Cox-2 inhibitors. This process of development has been advanced through the contributions of innumerable investigators, starting with Bayer and continuing today.

Contrast that situation with that of homeopathy. After over two hundred years, there is no single condition for which homeopathy is proven to be effective. The mechanism of action is unknown. The principles of therapy have remained unchanged since it was discovered by its founder and individuals who employ the therapy have added little to the original tenets. If homeopathy is science, it appears not to be advancing.

One simple explanation for the purported effects of homeopathy would be that it is a placebo. Such an explanation would answer the many various questions regarding the therapy. Were homeopathic medications placebo, no physical mechanism by which they could have an effect would be expected to be found. The results of clinical trials would be expected to be frequently confusing, disappointing and/or irreproducible if such trials were in fact comparing one placebo to another. Higher dilution medications would certainly be expected to be safe if they were merely water, water/alcohol mixtures or lactose tablets. Such an explanation, while understandably objectionable to proponents of the therapy, also appears to be reasonable, adequate and sufficient, given the current state of research.

Were homeopathy to prove an effective therapy, it would be irrational for any legitimate medical practitioner to ignore or fail to employ it. Given the apparent lack of adverse effects from high dilution homeopathic remedies, such a therapy should be readily embraced if it were effective. Indeed, open-mindedness is one of the hallmarks of science and the rapid assimilation of new therapies and technologies has been a consistent characteristic of scientific medicine. In fact, studies have shown that practitioners of mainstream medicine are less dogmatic than those of its alternatives.66, 67 To quote the late Dr. Carl Sagan, “…at the heart of science is an essential balance between two seemingly contradictory attitudes — an openness to new ideas, no matter how bizarre or counterintuitive, and the most ruthlessly skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense.”68

There is nothing wrong with the hypothesis that homeopathic remedies, no matter how implausible, are effective. However, such a hypothesis is amenable to scientific testing. Proper trials of homeopathic remedies should be easy to conduct. However, whether they are evaluated by review, by meta-analysis or by postulated physical mechanism, there is no good evidence to date that homeopathic remedies are effective treatments for any condition in human or in veterinary medicine. Nor is there evidence that they are superior to already established therapies.

Every practitioner of medicine requires faith in his or her methods in order to be confident. However, faith is not a legitimate foundation on which to build a practice of scientific medicine. Furthermore, in order for people to change their minds, they must have a good reason to do so; mere faith is not such a reason. Advocates of ethical medicine and veterinary science demand reliable evidence of both efficacy and safety before employing therapies to treat their patients. Thus, the question remains; if homeopathic remedies are safe and effective, why have its practitioners and proponents been unwilling or unable to conduct the proper trials and research required to prove it?

At present, the density of ordinary baryons and radiation in the universe is estimated to be equivalent to about one hydrogen atom per cubic meter of space. Only about 4% of the total energy density in the universe (as inferred from gravitational effects) can be seen directly. About 22% is thought to be composed of dark matter. The remaining 74% is thought to consist of dark energy, an even stranger component, distributed diffusely in space. Some hard-to-detect baryonic matter (see baryonic dark matter) makes a contribution to dark matter, but constitutes only a small portion. Determining the nature of this missing mass is one of the most important problems in modern cosmology and particle physics. Its urgency is underlined by David B. Cline in a 2003 article in Scientific American, in which he writes: “The terms . . . ‘dark matter’ and ‘dark energy,’ serve mainly as expressions of our ignorance”, much as the marking of early maps with ‘Terra Incognita’.
Observational evidence for dark matter
The first to propose the existence of a phenomena that has come to be called “dark matter” was Swiss astrophysicist Fritz Zwicky, of the California Institute of Technology (Caltech) in 1933. He applied the virial theorem to the Coma cluster of galaxies and obtained evidence of unseen mass. Zwicky estimated the total amount of mass in a cluster of galaxies, the Coma Cluster, based on the motions of the galaxies near the edge of the cluster. When he compared this mass estimate to one based on the number of galaxies and total brightness of the cluster, he found that there was about 400 times more mass than expected. The gravity of the visible galaxies in the cluster would be far too small for such fast orbits, so something extra was required. This is known as the “missing mass problem”. Based on these conclusions, Zwicky inferred that there must be some other form of matter existent in the cluster which we have not detected, which provides enough of the mass and gravity to hold the cluster together.
Much of the evidence for dark matter comes from the study of the motions of galaxies. Many of these appear to be fairly uniform, so by the virial theorem the total kinetic energy should be half the total gravitational binding energy of the galaxies. Experimentally, however, the total kinetic energy is found to be much greater: in particular, assuming the gravitational mass is due to only the visible matter of the galaxy, stars far from the center of galaxies have much higher velocities than predicted by the virial theorem. Galactic rotation curves, which illustrate the velocity of rotation versus the distance from the galactic center, cannot be explained by only the visible matter. Assuming that the visible material makes up only a small part of the cluster is the most straightforward way of accounting for this. Galaxies show signs of being composed largely of a roughly spherical halo of dark matter with the visible matter concentrated in a disc at the center. Low surface brightness dwarf galaxies are important sources of information for studying dark matter, as they have an uncommonly low ratio of visible matter to dark matter, and have few bright stars at the center which impair observations of the rotation curve of outlying stars.

Galactic rotation curves

Rotation curve of a typical spiral galaxy: predicted (A) and observed (B). Dark matter can explain the velocity curve having a “flat” appearance out to large radii.
For nearly 40 years after Zwicky’s initial observations, no other corroborating observations indicated that the mass to light ratio was anything other than unity (a high mass-to-light ratio indicates the presence of dark matter). Then in the late 1960s and early 1970s, Vera Rubin, a young astronomer at the Department of Terrestrial Magnetism at the Carnegie Institution of Washington began to present findings based on a new sensitive spectrograph that could measure the velocity curve of edge-on spiral galaxies to a greater degree of accuracy than had ever before been achieved. Together with fellow staff-member Kent Ford, Rubin announced at a 1975 meeting of the American Astronomical Society the astonishing discovery that most stars in spiral galaxies orbit at roughly the same speed which implied that their mass densities were uniform well beyond the locations with the most of the stars (the galactic bulge). This result suggests that either Newtonian gravity does not apply universally or that, conservatively, upwards of 50% of the mass of galaxies was contained in the relatively dark galactic halo. Met with skepticism, Rubin insisted that the observations were correct. She was not unaccustomed to controversy — both her master’s and PhD work were openly ridiculed and rejected for publication years earlier. Eventually other astronomers began to corroborate her work and it soon became well-established that most galaxies were in fact dominated by “dark matter”; the exception appeared to be galaxies with mass-to-light ratios close to that of stars.
Subsequent to this, numerous observations have been made that indicate the presence of dark matter in various parts of the cosmos. Together with Rubin’s findings for spiral galaxies and Zwicky’s work on galaxy clusters, the observational evidence for dark matter has been collecting over the decades to the point that today most astrophysicists accept its existence as a matter of course. As a unifying concept, it is one of the dominant features considered in the analysis of structures on the order of galactic scales and larger.

Velocity dispersions of galaxies
Rubin’s pioneering work has stood the test of time. Measurements of velocity curves in spiral galaxies were soon followed up with velocity dispersions of elliptical galaxies. While sometimes appearing with lower mass-to-light ratios, measurements of ellipticals still indicate a relatively high dark matter content. Likewise, measurements of the diffuse interstellar gas found at the edge of galaxies indicate not only dark matter distributions that extend beyond the visible limit of the galaxies, but also that the galaxies are virialized up to ten times their visible radii. This has the effect of pushing up the dark matter as a fraction of the total amount of gravitating matter from 50% measured by Rubin to the now accepted value of nearly 95%.
There are places where dark matter seems to be a small or totally absent component. Globular clusters show no evidence that they contain dark matter, though their orbital interactions with galaxies do show evidence for galactic dark matter. For some time, measurements of the velocity profile of stars seemed to indicate concentration of dark matter in the disk of the Milky Way galaxy, however, now it seems that the high concentration of baryonic matter in the disk of the galaxy (especially in the interstellar medium) can account for this motion. Galaxy mass profiles are thought to look very different from the light profiles. The typical model for dark matter galaxies is a smooth, spherical distribution in virialized halos. Such would have to be the case to avoid small-scale (stellar) dynamical effects. Recent research reported in January 2006 from the University of Massachusetts, Amherst would explain the previously mysterious warp in the disk of the Milky Way by the interaction of the Large and Small Magellanic Clouds and the predicted 20 fold increase in mass of the Milky Way taking into account dark matter.
Recently, astronomers from Cardiff University claim to have discovered a galaxy made almost entirely of dark matter, 50 million light years away in the Virgo Cluster, which was named VIRGOHI21 (Wikinews, New Scientist). Unusually, VIRGOHI21 does not appear to contain any visible stars: it was seen with radio frequency observations of hydrogen. Based on rotation profiles, the scientists estimate that this object contains approximately 1000 times more dark matter than hydrogen and has a total mass of about 1/10th that of the Milky Way Galaxy we live in. For comparison, the Milky Way is believed to have roughly 10 times as much dark matter as ordinary matter. Models of the Big Bang and structure formation have suggested that such dark galaxies should be very common in the universe, but none have previously been detected. If the existence of this dark galaxy is confirmed, it provides strong evidence for the theory of galaxy formation and poses problems for alternative explanations of dark matter.

Missing matter in galactic clusters

Strong gravitational lensing as observed by the Hubble Space Telescope in Abell 1689 indicates the presence of dark matter – Enlarge the image to see the lensing arcs.
Dark matter affects galaxy clusters as well. X-ray measurements of hot intracluster gas correspond closely to Zwicky’s observations of mass-to-light ratios for large clusters of nearly 10 to 1. Many of the experiments of the Chandra X-ray Observatory use this technique to independently determine the mass of clusters.
The galaxy cluster Abell 2029 is composed of thousands of galaxies enveloped in a cloud of hot gas, and an amount of dark matter equivalent to more than 1014 Suns. At the center of this cluster is an enormous, elliptically shaped galaxy that is thought to have been formed from the mergers of many smaller galaxies. More info is available here: [5] . The measured orbital velocities of galaxies within galactic clusters have been found to be consistent with dark matter observations.
Another important tool for future dark matter observations is gravitational lensing. Lensing relies on the effects of general relativity to predict masses without relying on dynamics, and so is a completely independent means of measuring the dark matter. Strong lensing, the observed distortion of background galaxies into arcs when the light passes through a gravitational lens, has been observed around a few distant clusters including Abell 1689 (pictured right). By measuring the distortion geometry, the mass of the cluster causing the phenomena can be obtained. In the dozens of cases where this has been done, the mass-to-light ratios obtained correspond to the dynamical dark matter measurements of clusters.
Perhaps more convincing, a technique has been developed over the last 10 years called weak lensing which looks at microscale distortions of galaxies observed in vast galaxy surveys due to foreground objects through statistical analyses. By examining the shear deformation of the adjacent background galaxies, astrophysicists can characterize the mean distribution of dark matter by statistical means and have found mass-to-light ratios that correspond to dark matter densities predicted by other large-scale structure measurements. The correspondence of the two gravitational lens techniques to other dark matter measurements have convinced almost all astrophysicists that dark matter actually exists as a major component of the universe’s composition. 

Structure formation
Dark matter is crucial to the Big Bang model of cosmology as a component which corresponds directly to measurements of the parameters associated with Friedmann cosmology solutions to general relativity. In particular, measurements of the cosmic microwave background anisotropies correspond to a cosmology where much of the matter interacts with photons more weakly than the known forces that couple light interactions to baryonic matter. Likewise, a significant amount of non-baryonic, cold matter is necessary to explain the large-scale structure of the universe.
Observations suggest that structure formation in the universe proceeds hierarchically, with the smallest structures collapsing first and followed by galaxies and then clusters of galaxies. As the structures collapse in the evolving universe, they begin to “light up” as the baryonic matter heats up through gravitational contraction and the object approaches hydrostatic pressure balance. Ordinary baryonic matter had too high a temperature, and too much pressure left over from the big bang to collapse and form smaller structures, such as stars, via the Jeans instability. Dark matter acts as a compactor of structure. Amazingly, this model not only corresponds with statistical surveying of the visible structure in the universe but also corresponds precisely to the dark matter predictions of the cosmic microwave background.
This bottom up model of structure formation requires something like cold dark matter to succeed. Large computer simulations of billions of dark matter particles have been used to confirm that the cold dark matter model of structure formation is consistent with the structures observed in the universe through galaxy surveys, such as the Sloan Digital Sky Survey and 2dF Galaxy Redshift Survey, as well as observations of the Lyman-alpha forest. These studies have been crucial in constructing the Lambda-CDM model which measures the cosmological parameters, including the fraction of the universe made up of baryons and dark matter.

Harry
· The true and final loyalty of Severus Snape and Draco Malfoy should be revealed, with an explanation of Dumbledore’s death at the hands of Snape, and in Snape’s reporting of the prophecy about Harry Potter to Voldemort. A confrontation between Snape and Harry is expected.
· Dumbledore’s brother Aberforth, mentioned briefly in Goblet of Fire (Ch. 24), will appear as a major character, probably the barman of the Hog’s Head.
· Wormtail may play a significant role in upcoming events. At the end of Prisoner of Azkaban (ch. 22), Dumbledore tells Harry:
“Pettigrew owes his life to you. You have sent Voldemort a deputy who is in your debt. . . . When one wizard saves another wizard’s life, it creates a certain bond between them . . . and I’m much mistaken if Voldemort wants his servant in the debt of Harry Potter. . . . This is magic at its deepest, its most impenetrable, Harry. But trust me . . . the time may come when you will be very glad you saved Pettigrew’s life.”
Information from J.K. Rowling
· J.K. Rowling said that Harry might get another pet at some point. She also hinted that Fawkes, Dumbledore’s phoenix, might have another role.
· In an interview with Tatler magazine, J.K. Rowling confirmed that she had decided upon a title, saying: “I so nearly told you the title, it almost popped out…”. Like the other books in the series, it is expected to begin with “Harry Potter and the…”.
· Rowling wrote the last chapter of the book some time ago, to give her an ending to work up to. The last word of the seventh book, according to Rowling, is currently “scar” [3], but she has also said it may change, along with the whole last chapter she has previously written. This last chapter contains details of what happens to each surviving character.
“This is the thing that I was very dubious about showing you… (T)his is the final chapter of book seven. This is really where I wrap everything up, it’s the epilogue. And I basically say what happens to everyone after they leave school – those who survive – because there are deaths – more deaths coming. It was a way of saying to myself, ‘Well, you will get it, you will get to book seven one day. And then you’ll need this!’ So I’d just like to remind all the children I know who come around my house and start sneaking into cupboards that it’s not there anymore – I don’t keep it at home anymore for very, very, very obvious reasons. So there it is.” J. K. Rowling

· JKR has stated that she has had enough of writing about Quidditch, and there will be no Quidditch matches in Book 7.
· We will learn something very important about Lily in book seven:
“Now, the important thing about Harry’s mother – the really, really significant thing – you’re going to find out in two parts. You’ll find out a lot more about her in book five, or you’ll find out something very significant about her in book five, and you’ll find out something incredibly important about her in book seven.” J. K. Rowling
.JKR has long said that Harry’s eyes resembling his mother’s is important.
· Severus Snape has been an important and enigmatic character throughout the books, as his true loyalty has always remained unclear. It is to be anticipated that as a surviving major character his loyalty will be settled in the final confrontation of the book.
Questioner: There’s an important kind of redemptive pattern to Snape.
JKR: He, um, there’s so much I wish I could say to you, and I can’t because it would ruin. I promise you, whoever asked that question, can I just say to you that I’m slightly stunned that you’ve said that and you’ll find out why I’m so stunned if you read Book Seven. That’s all I’m going to say.[6]
· She has stated we will learn more about Peter Pettigrew and Dumbledore.

· She refused to comment when asked whether the locked door in the Department of Mysteries in the Ministry of Magic would feature in the final book.
· At the Edinburgh book festival, Rowling mentioned that something more would be revealed about Petunia Dursley. Nothing of note occurred in book 6, so this remains to be discovered.
“..there is a little bit more to Aunt Petunia than meets the eye…She is not a squib, although that is a very good guess. Oh, I am giving a lot away here. I am being shockingly indiscreet”.
· Whether related or not, Rowling has also said that some non-magical character will perform magic late in life in desperate circumstances. However she has also said that Aunt Petunia will not perform magic.
· Also at Edinburgh, Rita Skeeter was mentioned: “She is loathsome…but I can’t help admiring her toughness.. There is more to come on Rita”
· And on Dolores Umbridge, “It’s too much fun to torture her not to have another little bit more before I finish”
· Viktor Krum is set for a reappearance. 
· We will discover what was Dudley’s sad memory when he stood in front of the Dementors in Wisteria Walk.
· The two-way mirror given to Harry by Sirius, and his flying motorbike will return. Rowling refused to comment whether Sirius Black himself might in some way reappear, but said there was a reason why he had to die.
· Dumbledore was seen to have a ‘gleam of triumph’ in his eyes when told that Voldemort had restored his body using Harry’s blood, at the end of Goblet of Fire (ch. 36,Parting of the ways). Rowling has confirmed that this is “still enormously significant”.
· Someone from Harry’s class, not who most readers would expect, and also not Ron, will become a Hogwarts teacher. This seems to indicate that Hogwarts will indeed reopen, though possibly not until the events of book 7 have transpired.
· JK Rowling has been consulted on the film versions of the books, so as to ensure that important aspects of the story do not get omitted or changed. After completion of Prisoner of Azkaban she was interviewed and commented that she was startled by clues which had crept into the film, relating to the final outcome of the series. In particular, she referred to the scene where Remus Lupin talks to Harry about his mother, but she may have meant other scenes as well.

· On her website, in the Rumours Sections, there is the question, Book Seven will be called “Harry Potter And The Pyramids of Furmat”, this is answered by J. K. Rowling with: The Pyramids Of Furmat lie a few miles east of the famous Fortress Of Shadows, not far from the magnificent Pillar Of Storgé. Many tourists prefer to view these ancient monuments at night, when they are illuminated by the Green Flame Torch. All of these ‘landmarks’ are really former rumored names for the various Harry Potter books, so it is unlikely they will be mentioned in Book Seven, unless put in as some sort of gag.
· There are indications that “at least two” of the main characters will die. In a June 2006 interview about the previously-written ending, JK Rowling admitted that:
“One character got a reprieve, but I have to say two die that I didn’t intend to die…A price has to be paid. We are dealing with pure evil…They go for the main characters, or I do”.
· When further questioned in June 2006 about authors who kill off their main characters, Rowling said “I can completely understand, however, the mentality of an author who thinks, well, I’m going to kill them off because that means there can be no non-author-written sequels’”.
Spoilers end here.

Beyond Book Seven
· There isn’t a university after Hogwarts and further Harry Potter books. :Q: Do you think that you will write about Harry after he graduates from Hogwarts? Isn’t there a University of Wizardry?
A: (T)here’s no University for Wizards. At the moment I’m only planning to write seven Harry Potter books. I won’t say “never,” but I have no plans to write an eighth book.
· When asked about other books similar to Quidditch Through the Ages and Fantastic Beasts and Where to Find Them, Rowling has said that she would consider writing them at some point and that they would also be written for charity. She also mentions writing an encyclopedia-style tome on all the major characters, also for charitable purposes.
· Shortly before the release of book 5, in an interview for the BBC, she was asked about Harry’s future by Jeremy Paxman:
JEREMY PAXMAN: So you know what is going to become of all the major characters over the span of the series?
JK ROWLING: Yeah..yeah.
JEREMY PAXMAN: Why stop when they grow up? Might be interesting to know what becomes of Harry as an adult.
JK ROWLING: How do you know he’ll still be alive?
JEREMY PAXMAN: Oh. At the end of book seven?
JK ROWLING: It would be one way to kill off the merchandising.
· When questioned about possible future books, she jokingly suggested Harry Potter’s mid-life crisis?

Biography

Stephen Hawking was born on 8 January 1942 to Frank Hawking, a prominent research biologist, and Isobel Hawking. He had two younger sisters, Philippa and Mary, and an adopted brother, named Edward.
Hawking’s parents moved from North London to Oxford for his birth because it was safer, since London was at that time under German bombardment. After the birth they moved back to London, where his father headed the division of parasitology at the National Institute for Medical Research.
In 1950, Hawking and his family moved to St Albans in Hertfordshire where, from the age of 11, he attended St Albans School, where he was a good but not exceptional student[2]. to this day, he will still come into the school and occasionaly lecture on physics. He was always interested in science, but decided that medicine and biology were “too inexact, too descriptive”. [2] He applied to study mathematics at University College, Oxford, but after one year changed to physics instead. He read for his PhD at Trinity Hall, Cambridge. He was seen as being an extraordinary student. His physics tutor, Robert Berman, later said in the New York Times Magazine, “It was only necessary for him to know that something could be done, and he could do it without looking to see how other people did it. … He didn’t have very many {books}, and he didn’t take notes. Of, course, his mind was completely different from all of his contemporaries.” He was popular with his fellow students, but his unimpressive study habits gave him a final examination score on the borderline between first and second class honors, making an oral examination necessary. Berman said of the oral examination, “And of course the examiners then were intelligent enough to realize they were talking to someone far cleverer than most of themselves.”
After receiving his B.A. degree at Oxford in 1962, he stayed at Oxford to study astronomy, deciding to leave when he found that studying sunspots, which was all the observatory was equipped for, didn’t appeal to him and that he was more interested in theory than in observation. He left Oxford for Cambridge University, where he engaged in the study of theoretical astronomy and cosmology.

Almost as soon as he arrived at Cambridge, he was struck by the motor neuron disease which would cost him the loss of almost all neuromuscular control. During his first two years at Cambridge, he was less than impressive, but, after the disease had stabilized and with the help of his doctoral tutor, Dennis William Sciama, he returned to working on his Ph.D.[2] Hawking later said that he thinks the real turning point was his 1965 marriage to Jane Wilde, a language student.
Hawking was elected as one of the youngest Fellows of the Royal Society in 1974, was created a Commander of the Order of the British Empire in 1982, and became a Companion of Honour in 1989. Prof. Hawking is a member of the Board of Sponsors of The Bulletin of the Atomic Scientists

Research fields
Hawking’s principal fields of research are theoretical cosmology and quantum gravity.

In the late 1960s, he and his Cambridge friend and colleague, Roger Penrose, applied a new, complex mathematical model they had created to Albert Einstein’s general theory of relativity. This led, in 1971, to Hawking proving the first of many singularity theorems; such theorems provide a set of sufficient conditions for the existence of a singularity in space-time. This work showed that, far from being mathematical curiosities which appear only in special cases, singularities are a fairly generic feature of general relativity.

Hawking also suggested that, after the Big Bang, primordial or mini black holes were formed. With Bardeen and Carter, he proposed the four Laws of black hole mechanics, drawing an analogy with thermodynamics. In 1974, he calculated that black holes should thermally create and emit subatomic particles, known as Hawking radiation, until they exhaust their energy and evaporate.

In collaboration with Jim Hartle, Hawking developed a model in which the Universe had no boundary in space-time, replacing the initial singularity of the classical Big Bang models with a region akin to the North pole; while one cannot travel North of the North pole, there is no boundary there. While originally the no-boundary proposal predicted a closed Universe, discussions with Neil Turok led to the realization that the no-boundary proposal is consistent with a Universe which is not closed also.

Illness
Hawking is severely disabled by amyotrophic lateral sclerosis, or ALS (a type of motor neuron disease commonly known in the United States as Lou Gehrig’s disease).

When he was young, he was athletic (although Hawking’s biography on his official website would seem to deny this) [verification needed] and enjoyed riding horses and playing with the other children. At Oxford, he coxed a rowing team, which, he stated, helped relieve his immense boredom at university. Symptoms of the disorder first appeared while he was enrolled at Cambridge. He lost balance and fell downstairs, hitting his head. Worried of losing his genius, he took the Mensa International test, to verify that his intellectual abilities were intact. Diagnosis came when Hawking was 21, shortly before his first marriage, and doctors said he would not survive more than two or three years. He battled the odds and has survived much longer than most sufferers of ALS, although he has become increasingly disabled by the gradual progress of the disease.

He gradually lost the use of his arms, legs, and voice, and is now almost completely paralysed. The computer system attached to his wheelchair is operated by Hawking via an infra-red ‘blink switch’ clipped onto his glasses. By scrunching his right cheek up, he is able to talk, compose speeches, research papers, browse the World Wide Web and write e-mail. The system also uses radio transmission to provide control over doors in his home and office.

During a visit to the research center CERN in Geneva in 1985, Hawking contracted pneumonia, which in his condition was life-threatening. It resulted in acute difficulty of breathing, which could only be overcome through a tracheostomy by which Stephen Hawking lost his natural speech ability. He has since used an electronic voice synthesizer to communicate. The voice synthesizer, which has an American accent, is of a model that is no longer produced. Asked why he has still kept it after so many years, Hawking mentioned that he has not heard a voice he likes better and because he identifies with it. Hawking is said to be looking for a replacement since, other than being obsolete, the synthesizer, a DECtalk DTC01 is now considered large and fragile but as of present, finding a software alternative has been difficult. During a lecture in Hong Kong in June 2006, he joked that if he got a new one with a French accent, his wife would divorce him.

When Hawking (then using a wheelchair and unable to dress himself) and his wife were first living together, they received no outside assistance other than from physics students who helped in exchange for extra attention with their work. As his condition worsened, Hawking needed a team of nurses to provide round-the-clock care. He also needed a wheelchair for mobility.

Despite his disease, he describes himself as “lucky” — not only has the slow progress of his disease provided time to make influential discoveries, it has also afforded time to have, in his own words, “a very attractive family”. When Jane was asked why she decided to marry a man with a 3-year life expectancy, she responded: “These were the days of atomic gloom and doom, so we all had rather a short life expectancy.”

Hawking’s wife cared for him until 1991 when the couple separated under the pressures of fame, his increasing disability, and an affair Hawking began with one of his nurses, Elaine Mason. He and Elaine Mason were married in 1995. (Elaine Mason’s first husband, David Mason, had designed the first version of Hawking’s talking computer.) A 2004 Vanity Fair article by Judy Bachrach indicated allegations of violence between Hawking and his first wife, though a police investigation into the matter that same year was inconclusive.

In 1999, Jane Hawking published a memoir, Music to Move the Stars, detailing her own long-term relationship with a family friend whom she later married. Hawkings’ daughter Lucy Hawking is a novelist. Their son Robert Hawking emigrated to the United States, married, and has one child, George Edwardz.

Distinction
Hawking’s belief that the average person should have access to his work led him to write a series of popular science books in addition to his academic work. The first of these, A Brief History of Time, was published on April 1, 1988 by Hawking, his family and friends, and some leading physicists. It became a documentary in 1991. It surprisingly became a best-seller and was followed by The Universe in a Nutshell (2001).

Both books have remained highly popular all over the world. A collection of essays titled Black Holes and Baby Universes (1993) was also popular. He has now written a new book, A Briefer History of Time (2005) that aims to update his earlier works and make them accessible to a wider audience. He has recently announced that he plans to write a children’s book focusing on science that has been described to be “like Harry Potter, but without the magic.”

Hawking is also known for his wit; he is famous for his oft-made statement, “When I hear of Schrödinger’s cat, I reach for my pistol.” This was a deliberately ironic paraphrase of the phrase “Whenever I hear the word culture… I release the safety-catch of my Browning !”, from a play Schlageter (Act 1, Scene 1) by German playwright and Nazi Poet Laureate, Hanns Johst.

His wit has both entertained the non-specialist public and helped them to understand complex questions. Asked in October 2005 on the British daytime chat show Richard & Judy, to explain his assertion that the question “What came before the Big Bang?” was meaningless, he compared it to asking “What lies north of the north pole?”

Hawking is an active supporter of various causes. He appeared on a political broadcast for the United Kingdom’s Labour Party, and actively supports the children’s charity SOS Children’s Villages UK.

He recently made the news for announcing that he believes colonization on other planets and/or the moon is imperative to ensure the continuation of the human race.

Comments on global warming
In the third week of June 2006, Stephen Hawking spoke in China and made the statement that humans might have already fried the atmosphere and inadvertently reconnected the planet Earth with her dead neighbours.

The China Daily asked Hawking about the environment, and he responded that he was “very worried about global warming.” He said he was afraid that Earth “might end up like Venus, at 250 degrees Celsius and raining sulfuric acid.” In the light of this discussion it is believed that Stephen Hawking asked an open question on Yahoo Answers “How can the human race survive the next hundred years?” and received well over 25,000 responses. The validity of the question was confirmed by Hawking himself and the Yahoo Answers staff. An answer has already been chosen.

In an ABC News interview in August 2006, Hawking explained, “The danger is that global warming may become self-sustaining, if it has not done so already. The melting of the Arctic and Antarctic ice caps reduces the fraction of solar energy reflected back into space, and so increases the temperature further. Climate change may kill off the Amazon and other rain forests, and so eliminate one of the main ways in which carbon dioxide is removed from the atmosphere. The rise in sea temperature may trigger the release of large quantities of carbon dioxide, trapped as hydrides on the ocean floor. Both these phenomena would increase the greenhouse effect, and so further global warming. We have to reverse global warming urgently, if we still can.” He also said that nuclear war and genetically engineered biological weapons were major threats to the human race.

Losing an old bet

Hawking was in the news in July 2004 for presenting a new theory about black holes which goes against his own long-held belief about their behavior, thus losing a bet he made with Kip Thorne and John Preskill of Caltech. Classically, it can be shown that information crossing the event horizon of a black hole is lost to our universe, and that thus all black holes are identical beyond their mass, electrical charge and angular velocity (the “no hair theorem”).

The problem with this theorem is that it implies the black hole will emit the same radiation regardless of what goes into it, and as a consequence that if a pure quantum state is thrown into a black hole, an “ordinary” mixed state will be returned. This runs counter to the rules of quantum mechanics and is known as the black hole information paradox.

Another bet — about the existence of black holes — was described by Hawking as an “insurance policy” of sorts. To quote from his book, A Brief History of Time, “This was a form of insurance policy for me. I have done a lot of work on black holes, and it would all be wasted if it turned out that black holes do not exist. But in that case, I would have the consolation of winning my bet, which would win me four years of the magazine Private Eye. If black holes do exist, Kip will get one year of Penthouse. When we made the bet in 1975, we were 80% certain that Cygnus was a black hole. By now, I would say that we are about 95% certain, but the bet has yet to be settled.” (1988) According to the updated 10th anniversary edition of A Brief History of Time, Hawking has conceded the bet “to the outrage of Kip’s liberated wife” due to subsequent observational data in favour of black holes.

Hawking had earlier speculated that the singularity at the centre of a black hole could form a bridge to a “baby universe” into which the lost information could pass; such theories have been very popular in science fiction. But according to Hawking’s new idea, presented at the 17th International Conference on General Relativity and Gravitation, on 21 July 2004 in Dublin, Ireland, black holes eventually transmit, in a garbled form, information about all matter they swallow:

The Euclidean path integral over all topologically trivial metrics can be done by time slicing and so is unitary when analytically continued to the Lorentzian. On the other hand, the path integral over all topologically non-trivial metrics is asymptotically independent of the initial state. Thus the total path integral is unitary and information is not lost in the formation and evaporation of black holes. The way the information gets out seems to be that a true event horizon never forms, just an apparent horizon.

—GR Conference website summary of Hawking’s talk
Having concluded that information is conserved, Hawking conceded his bet in Preskill’s favour, awarding him Total Baseball, The Ultimate Baseball Encyclopedia. However, Thorne remains unconvinced of Hawking’s proof and declined to contribute to the award.

Trivia

Hawking is lefthanded

Spouses: Jane Wilde (m. 1965; div. 1990), Elaine Mason (m. 1995)

Children: Robert (b. 1967), Lucy (b. 1970), Timothy (b. 1979)

Awards
1975 Eddington Medal
1976 Hughes Medal of the Royal Society
1979 Albert Einstein Medal
1982 Order of the British Empire (Commander)
1985 Gold Medal of the Royal Astronomical Society
1986 Member of the Pontifical Academy of Sciences
1988 Wolf Prize in Physics
1989 Prince of Asturias Awards in Concord
1999 Julius Edgar Lilienfeld Prize of the American Physical Society
2003 Michelson Morley Award of Case Western Reserve University
2006 Copley Medal of the Royal Society

The surface temperature of the Sun is about 6,000° Kelvin, or 10,500° Fahrenheit. Compare that to the average Los Angeles temperature of 72°F or 295°K.
What is the Sun composed of?

In a chemical composition, the Sun is mostly made up of burning hydrogen and a small amount of helium. Aside from which, the Sun contains trace amounts of oxygen, carbon, nitrogen, and other gases.
Physically, the Sun is composed of an outermost layer called corona. Only visible during eclipses, it is a low density cloud of plasma with higher transparency than the inner layers. The white corona is a million times less bright than the inner layers of the sun, but is many times larger. Its temperature range from 1 million degrees Kelvin (or 2 million degrees Fahrenheit) to as much as 3 million degrees Kelvin (or 5 million degrees Fahrenheit). From the corona, several magnetic field patterns are being emitted, such as the violent solar flares, cool and quiet prominences, and the loose particles of solar winds.
The chromosphere can bee seen as a red circle around the outside of the sun during an eclipse. Its red coloring is caused by the abundance of hydrogen. Although the temperature from the Sun’s core to the photosphere decreases, the chromosphere’s temperature, however, is 7,000°K, hotter than that of the photosphere.
The photosphere is located below the chromosphere; a zone from which the sunlight we see is emitted. It is a thin layer of low-pressure gases measuring a few hundred kilometers thick, with a temperature of 6,000°K. The composition, temperature, and pressure of the photosphere are revealed by the spectrum of sunlight.
Sunspots are dark spots on the photosphere, with almost the same size of Earth. They are formed out of loops of the magnetic field opposing convection, resulting to a stoppage of energy flow to the surface. They have cooler temperatures than the photosphere with temperatures of up to 4,500°K. They appear and disappear over a period of 11 years.
Outside the core is the solar envelope, which puts pressure on the core and maintains the core’s temperature. It own temperature is measured at 4 million degrees Kelvin, but it is considered cooler and appears more opaque than the core.
The innermost layer of the sun is the core. Having a density of 160 grams per cubic centimeters—10 times that of lead—the core might be expected to be solid. However, its high temperature of 15 million degrees Kelvin keeps it in a gaseous state, creating an environment just right for nuclear reactions to occur. The core is the source of all the Sun’s energy. Fortunately for life on Earth, the Sun’s energy output is just about constant so we do not see much change in its brightness or the heat it gives off.
How was the sun formed?

Astronomers think that the Sun was formed from a giant cloud which was rotating slowly about five thousand million years ago. Whether this cloud was created by the Big Bang, we do not know for sure. Most of the cloud was made up of hydrogen gas and small amounts of oxygen, silicon, and carbon. Because of gravity, all of the gases wanted to concentrate in one place, but when the gas got closer to the axis of rotation, it started to rotate faster around that axis.
The fast rotation of the gas meant that it could not all be concentrated in one place, and what happened instead is that the gas concentrated in a flat disk with most of the materials in the center. The material in the center concentrated more until it got so hot and dense that it could start generating energy through nuclear fusion of the hydrogen. At that moment, the Sun becomes a star, while the rest of the material clumped together and formed the planets, including Earth.