In physics and mathematics, the dimension of a space or object is informally defined as the minimum number of coordinates needed to specify each point within it. Thus a line has a dimension of one because only one coordinate is needed to specify a point on it (for example, the point at 5 on a number line). A surface such as a plane or the surface of a cylinder or sphere has a dimension of two because two coordinates are needed to specify a point on it (for example, to locate a point on the surface of a sphere you need both its latitude and its longitude). The inside of a cube, a cylinder or a sphere is three-dimensional because three co-ordinates are needed to locate a point within these spaces.

In physical terms, ''dimension'' refers to the constituent structure of all space (cf. volume) and its position in time (perceived as a scalar dimension along the ''t''-axis), as well as the spatial constitution of objects within – structures that have correlations with both particle and field conceptions, interact according to relative properties of mass, and which are fundamentally mathematical in description. These or other axes may be referenced to uniquely identify a point or structure in its attitude and relationship to other objects and occurrences. Physical theories that incorporate time, such as general relativity, are said to work in 4-dimensional "spacetime", (defined as a Minkowski space). Modern theories tend to be "higher-dimensional" including quantum field and string theories. The state-space of quantum mechanics is an infinite-dimensional function space.

The concept of dimension is not restricted to physical objects. High-dimensional spaces occur in mathematics and the sciences for many reasons, frequently as configuration spaces such as in Lagrangian or Hamiltonian mechanics; these are abstract spaces, independent of the physical space we live in.

In mathematics

In mathematics, the dimension of an object is an intrinsic property, independent of the space in which the object may happen to be embedded. For example: a point on the unit circle in the plane can be specified by two Cartesian coordinates but one can make do with a single coordinate (the polar coordinate angle), so the circle is 1-dimensional even though it exists in the 2-dimensional plane. This ''intrinsic'' notion of dimension is one of the chief ways in which the mathematical notion of dimension differs from its common usages.

The dimension of Euclidean -space is . When trying to generalize to other types of spaces, one is faced with the question “what makes -dimensional?" One answer is that to cover a fixed ball in by small balls of radius , one needs on the order of such small balls. This observation leads to the definition of the Minkowski dimension and its more sophisticated variant, the Hausdorff dimension. But there are also other answers to that question. For example, one may observe that the boundary of a ball in looks locally like and this leads to the notion of the inductive dimension. While these notions agree on , they turn out to be different when one looks at more general spaces.

A tesseract is an example of a four-dimensional object. Whereas outside of mathematics the use of the term "dimension" is as in: "A tesseract ''has four dimensions''", mathematicians usually express this as: "The tesseract ''has dimension 4''", or: "The dimension of the tesseract ''is'' 4".

Although the notion of higher dimensions goes back to René Descartes, substantial development of a higher-dimensional geometry only began in the 19th century, via the work of Arthur Cayley, William Rowan Hamilton, Ludwig Schläfli and Bernhard Riemann. Riemann's 1854 Habilitationsschrift, Schlafi's 1852 ''Theorie der vielfachen Kontinuität'', Hamilton's 1843 discovery of the quaternions and the construction of the Cayley Algebra marked the beginning of higher-dimensional geometry.

The rest of this section examines some of the more important mathematical definitions of the dimensions.

Dimension of a vector space

The dimension of a vector space is the number of vectors in any basis for the space, i.e. the number of coordinates necessary to specify any vector. This notion of dimension (the cardinality of a basis) is often referred to as the ''Hamel dimension'' or ''algebraic dimension'' to distinguish it from other notions of dimension.

=== Manifolds === A connected topological manifold is locally homeomorphic to Euclidean -space, and the number is called the manifold's dimension. One can show that this yields a uniquely defined dimension for every connected topological manifold.

The theory of manifolds, in the field of geometric topology, is characterized by the way dimensions 1 and 2 are relatively elementary, the high-dimensional cases }} are simplified by having extra space in which to "work"; and the cases and are in some senses the most difficult. This state of affairs was highly marked in the various cases of the Poincaré conjecture, where four different proof methods are applied.

Lebesgue covering dimension

For any normal topological space , the Lebesgue covering dimension of is defined to be n if ''n'' is the smallest integer for which the following holds: any open cover has an open refinement (a second open cover where each element is a subset of an element in the first cover) such that no point is included in more than elements. In this case dim . For a manifold, this coincides with the dimension mentioned above. If no such integer exists, then the dimension of is said to be infinite, and one writes dim . Moreover, has dimension −1, i.e. dim if and only if is empty. This definition of covering dimension can be extended from the class of normal spaces to all Tychonoff spaces merely by replacing the term "open" in the definition by the term "functionally open".

Inductive dimension

An inductive definition of dimension can be created as follows. Consider a discrete set of points (such as a finite collection of points) to be 0-dimensional. By dragging a 0-dimensional object in some direction, one obtains a 1-dimensional object. By dragging a 1-dimensional object in a ''new direction'', one obtains a 2-dimensional object. In general one obtains an ()-dimensional object by dragging an dimensional object in a ''new'' direction.

The inductive dimension of a topological space could refer to the ''small inductive dimension'' or the ''large inductive dimension'', and is based on the analogy that )-dimensional}} balls have dimensional boundaries, permitting an inductive definition based on the dimension of the boundaries of open sets.

Hausdorff dimension

For sets which are of a complicated structure, especially fractals, the Hausdorff dimension is useful. The Hausdorff dimension is defined for all metric spaces and, unlike the Hamel dimension, can also attain non-integer real values. The box dimension or Minkowski dimension is a variant of the same idea. In general, there exist more definitions of fractal dimensions that work for highly irregular sets and attain non-integer positive real values. Fractals have been found useful to describe many natural objects and phenomenon.

Hilbert spaces

Every Hilbert space admits an orthonormal basis, and any two such bases for a particular space have the same cardinality. This cardinality is called the dimension of the Hilbert space. This dimension is finite if and only if the space's Hamel dimension is finite, and in this case the above dimensions coincide.

In physics

Spatial dimensions

Classical physics theories describe three physical dimensions: from a particular point in space, the basic directions in which we can move are up/down, left/right, and forward/backward. Movement in any other direction can be expressed in terms of just these three. Moving down is the same as moving up a negative distance. Moving diagonally upward and forward is just as the name of the direction implies; ''i.e.'', moving in a linear combination of up and forward. In its simplest form: a line describes one dimension, a plane describes two dimensions, and a cube describes three dimensions. (See Space and Cartesian coordinate system.)

Number of dimensions	Example co-ordinate systems
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Time

A temporal dimension is a dimension of time. Time is often referred to as the "fourth dimension" for this reason, but that is not to imply that it is a spatial dimension. A temporal dimension is one way to measure physical change. It is perceived differently from the three spatial dimensions in that there is only one of it, and that we cannot move freely in time but subjectively move in one direction.

The equations used in physics to model reality do not treat time in the same way that humans commonly perceive it. The equations of classical mechanics are symmetric with respect to time, and equations of quantum mechanics are typically symmetric if both time and other quantities (such as charge and parity) are reversed. In these models, the perception of time flowing in one direction is an artifact of the laws of thermodynamics (we perceive time as flowing in the direction of increasing entropy).

The best-known treatment of time as a dimension is Poincaré and Einstein's special relativity (and extended to general relativity), which treats perceived space and time as components of a four-dimensional manifold, known as spacetime, and in the special, flat case as Minkowski space.

Additional dimensions

Theories such as string theory and M-theory predict that physical space in general has in fact 10 and 11 dimensions, respectively. The extra dimensions are spatial. We perceive only three spatial dimensions, and no physical experiments have confirmed the reality of additional dimensions. A possible explanation that has been suggested is that space acts as if it were "curled up" in the extra dimensions on a subatomic scale, possibly at the quark/string level of scale or below.

Up to now, no experimental or observational signs of extra dimensions have been officially reported. An analysis of results from the Large Hadron Collider in December 2010 severely constrains theories with large extra dimensions.

Networks and dimension

Some complex networks are characterized by fractal dimensions. The concept of dimension can be generalized to include networks embedded in space. The dimension characterize their spatial constraints.

Literature

Perhaps the most basic way in which the word ''dimension'' is used in literature is as a hyperbolic synonym for ''feature'', ''attribute'', ''aspect'', or ''magnitude''. Frequently the hyperbole is quite literal as in ''he's so 2-dimensional'', meaning that one can see at a glance what he ''is''. This contrasts with 3-dimensional objects which have an interior that is hidden from view, and a back that can only be seen with further examination.

Science fiction texts often mention the concept of dimension, when really referring to parallel universes, alternate universes, or other planes of existence. This usage is derived from the idea that to travel to parallel/alternate universes/planes of existence one must travel in a direction/dimension besides the standard ones. In effect, the other universes/planes are just a small distance away from our own, but the distance is in a fourth (or higher) spatial (or non-spatial) dimension, not the standard ones.

One of the most heralded science fiction novellas regarding true geometric dimensionality, and often recommended as a starting point for those just starting to investigate such matters, is the 1884 novel ''Flatland'' by Edwin A. Abbott. Isaac Asimov, in his foreword to the Signet Classics 1984 edition, described ''Flatland'' as "The best introduction one can find into the manner of perceiving dimensions."

The idea of other dimensions was incorporated into many early science fiction stories, appearing prominently, for example, in Miles J. Breuer's ''The Appendix and the Spectacles'' (1928) and Murray Leinster's ''The Fifth-Dimension Catapult'' (1931); and appeared irregularly in science fiction by the 1940s. Some of the classic stories involving other dimensions include Robert A. Heinlein's 1941 ''—And He Built a Crooked House'', in which a California architect designs a house based on a three-dimensional projection of a tesseract, and Alan E. Nourse's ''Tiger by the Tail'' and ''The Universe Between'', both from 1951. Another reference would be Madeleine L'Engle's novel ''A Wrinkle In Time'' (1962) which uses the 5th Dimension as a way for "tesseracting the universe", or in a better sense, "folding" space in half to move across it quickly.

The fourth and fifth dimensions were also a key component of the book ''The Boy Who Reversed Himself'', by William Sleator.

Philosophy

In 1783, Kant wrote: "That everywhere space (which is not itself the boundary of another space) has three dimensions and that space in general cannot have more dimensions is based on the proposition that not more than three lines can intersect at right angles in one point. This proposition cannot at all be shown from concepts, but rests immediately on intuition and indeed on pure intuition ''a priori'' because it is apodictically (demonstrably) certain."

More dimensions

See also

Degrees of freedom

Dimension (data warehouse) and dimension tables

Dimensional analysis

Fractal dimension

Hyperspace (disambiguation page)

Space-filling curve

Intrinsic dimension

A list of topics indexed by dimension

Zero dimensions:

*Point

*Zero-dimensional space

*Integer

One dimension:

*Line

*Graph (combinatorics)

*Real number

Two dimensions:

*Complex number

*Cartesian coordinate system

*List of uniform tilings

*Surface

Three dimensions

*Platonic solid

*Stereoscopy (3-D imaging)

*Euler angles

*3-manifold

*Knot (mathematics)

Four dimensions:

*Spacetime

*Fourth spatial dimension

*Convex regular 4-polytope

*Quaternion

*4-manifold

High-dimensional topics from mathematics:

*Octonion

*Vector space

*Manifold

*Calabi–Yau spaces

High-dimensional topics from physics:

*Kaluza–Klein theory

*String theory

*M-theory

Infinitely many dimensions:

*Hilbert space

*Function space

References

Further reading

Edwin A. Abbott, (1884) ''Flatland: A Romance of Many Dimensions'', Public Domain. Online version with ASCII approximation of illustrations at Project Gutenberg.

Thomas Banchoff, (1996) ''Beyond the Third Dimension: Geometry, Computer Graphics, and Higher Dimensions, Second Edition'', Freeman.

Clifford A. Pickover, (1999) ''Surfing through Hyperspace: Understanding Higher Universes in Six Easy Lessons'', Oxford University Press.

Rudy Rucker, (1984) ''The Fourth Dimension'', Houghton-Mifflin.

Michio Kaku, (1994) ''Hyperspace, a Scientific Odyssey Through the 10th Dimension'', Oxford University Press.

Category:Physics Category:Abstract algebra Category:Algebra Category:Linear algebra

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name	Carl Sagan
birth date	November 09, 1934
birth place	Brooklyn, New York City, U.S.
residence	United States
nationality	American
death date	December 20, 1996
death place	Seattle, Washington, U.S.
death cause	Pneumonia
education	Rahway High School
alma mater	University of Chicago,Cornell University
field	Astronomy, Astrophysics, Cosmology, Astrobiology, Space science, Planetary science
work institutions	Cornell University Harvard University Smithsonian Astrophysical Observatory University of California, Berkeley
alma mater	University of Chicago (B.A.), (B.Sc.), (M.Sc.), (Ph.D.)
known for	Search for Extra-Terrestrial Intelligence (SETI) ''Cosmos: A Personal Voyage'' ''Cosmos'' Voyager Golden Record Pioneer plaque ''Contact'' ''Pale Blue Dot''
prizes	Oersted Medal (1990) NASA Distinguished Public Service Medal (twice) Pulitzer Prize for General Non-Fiction (1978) National Academy of Sciences Public Welfare Medal (1994) }}

Carl Edward Sagan () (November 9, 1934 December 20, 1996) was an American astronomer, astrophysicist, cosmologist, author, science popularizer, and science communicator in the space and natural sciences. During his lifetime, he published more than 600 scientific papers and popular articles and was author, co-author, or editor of more than 20 books. In his works, he advocated skeptical inquiry and the scientific method. He pioneered exobiology and promoted the Search for Extra-Terrestrial Intelligence (SETI).

Sagan became world-famous for his popular science books and for the award-winning 1980 television series ''Cosmos: A Personal Voyage'', which he narrated and co-wrote. A book to accompany the program was also published. Sagan also wrote the novel ''Contact'', the basis for the 1997 film of the same name.

Early life

Carl Sagan was born in Brooklyn, New York City, to a Ukrainian Jewish family. His father, Sam Sagan, was an immigrant garment worker from Kamenets-Podolsk, Ukraine; his mother, Rachel Molly Gruber, a housewife. Carl was named in honor of Rachel's biological mother, Chaiya Clara, in Sagan's words, "the mother she never knew." Sagan graduated from Rahway High School in Rahway, New Jersey, in 1951.

He had one sister, Carol, and the family lived in a modest apartment near the Atlantic Ocean, in Bensonhurst, a Brooklyn neighborhood. According to Sagan, they were Reform Jews, the most liberal of the three main Jewish groups. Both Sagan and his sister agree that their father was not especially religious, but that their mother "definitely believed in God, and was active in the temple ... and served only Kosher meat." During the height of the Depression, his father had to accept a job as a theater usher.

According to biographer Keay Davidson, Sagan's "inner war" was a result of his close relations with both his parents, who were in many ways "opposites." Sagan traced his later analytical urges to his mother, a woman who had known "extreme poverty as a child," and had grown up almost homeless in New York City during World War I and the 1920s. She had her own intellectual ambitions as a young woman, but they were blocked by social restrictions, because of her poverty, her being a woman and wife, and her Jewish religion. Davidson notes that she therefore "worshiped her only son, Carl. He would fulfill her unfulfilled dreams."

However, his "sense of wonder" came from his father, who was a "quiet and soft-hearted escapee from the Czar." In his free time, he gave apples to the poor, or helped soothe labor-management tensions within New York's "tumultuous" garment industry. Although he was "awed" by Carl's "brilliance, his boyish chatter about stars and dinosaurs," he took his son's inquisitiveness in stride, as part of his growing up. In his later years as a writer and scientist, Sagan would often draw on his childhood memories to illustrate scientific points, as he did in his book, ''Shadows of Forgotten Ancestors''. Sagan describes his parents' influence on his later thinking:

:''My parents were not scientists. They knew almost nothing about science. But in introducing me simultaneously to skepticism and to wonder, they taught me the two uneasily cohabiting modes of thought that are central to the scientific method.''

1939 World's Fair

Sagan recalls that one of his best experiences was when he was four or five years old, his parents took him to the 1939 New York World's Fair. The exhibits became a turning point in his life. He later recalled the moving map of the "America of Tomorrow" exhibit: "It showed beautiful highways and cloverleaves and little General Motors cars all carrying people to skyscrapers, buildings with lovely spires, flying buttresses — and it looked great!" At other exhibits, he remembered how a flashlight that shined on a photoelectric cell created a cracking sound, and how the sound from a tuning fork became a wave on an oscilloscope. He also witnessed the future media technology that would replace radio: television. Sagan wrote:

:''Plainly, the world held wonders of a kind I had never guessed. How could a tone become a picture and light become a noise?''

He also saw one of the Fair's most publicized events, the burial of a time capsule at Flushing Meadows, which contained mementos of the 1930s to be recovered by Earth's descendants in a future millennium. "The time capsule thrilled Carl," writes Davidson. As an adult, Sagan and his colleagues created similar time capsules, but ones that would be sent out into the galaxy. These were the Pioneer plaque and the ''Voyager Golden Record'' records, all of which were spinoffs of Sagan's memories of the World Fair.

World War II

During World War II, Sagan's family worried about the fate of their European relatives. Sagan, however, was generally unaware of the details of the ongoing war. He writes, "Sure, we had relatives who were caught up in the Holocaust. Hitler was not a popular fellow in our household ... But on the other hand, I was fairly insulated from the horrors of the war." His sister, Carol, said that their mother "above all wanted to protect Carl ... She had an extraordinarily difficult time dealing with World War II and the Holocaust." Sagan's book, ''The Demon-Haunted World'' (1996), included his memories of this conflicted period in his life, where his family dealt with the realities of the war in Europe, but tried to prevent it from undermining his optimistic spirit.

Inquisitiveness about nature

Soon after entering elementary school, he began to express a strong inquisitiveness about nature. Sagan recalled taking his first trips to the public library alone, at the age of five, when his mother got him a library card. He wanted to learn what stars were, since none of his friends or their parents could give him a clear answer: :''I went to the librarian and asked for a book about stars ... And the answer was stunning. It was that the Sun was a star but really close. The stars were suns, but so far away they were just little points of light ... The scale of the universe suddenly opened up to me. It was a kind of religious experience. There was a magnificence to it, a grandeur, a scale which has never left me. Never ever left me.''

About the time he was six or seven, he and a close friend took trips to the American Museum of Natural History in New York City. While there, they went to the Hayden Planetarium and walked around the museum's exhibits of space objects, such as meteorites, and displays of dinosaurs and animals in natural settings. Sagan writes about those visits: :''I was transfixed by the dioramas — lifelike representations of animals and their habitats all over the world. Penguins on the dimly lit Antarctic ice; ... a family of gorillas, the male beating his chest, ... an American grizzly bear standing on his hind legs, ten or twelve feet tall, and staring me right in the eye.''

His parents helped nurture his growing interest in science by buying him chemistry sets and reading materials. His interest in space, however, was his primary focus, especially after reading science fiction stories by writers such as Edgar Rice Burroughs, which stirred his imagination about life on other planets, such as Mars. According to biographer Ray Spangenburg, these early years as Sagan tried to understand the mysteries of the planets, became a "driving force in his life, a continual spark to his intellect, and a quest that would never be forgotten."

Education and scientific career

He attended the University of Chicago, where he participated in the Ryerson Astronomical Society, received a bachelor of arts with general and special honors in 1954, a bachelor of science in 1955, and a master of science in physics in 1956 before earning a PhD in astronomy and astrophysics in 1960. During his time as an undergraduate, Sagan worked in the laboratory of the geneticist H. J. Muller. From 1960 to 1962 Sagan was a Miller Fellow at the University of California, Berkeley. From 1962 to 1968, he worked at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts.

Sagan lectured and did research at Harvard University until 1968, when he moved to Cornell University in Ithaca, New York. He became a full Professor at Cornell in 1971, and he directed the Laboratory for Planetary Studies there. From 1972 to 1981, Sagan was the Associate Director of the Center for Radio Physics and Space Research at Cornell.

Sagan was associated with the American space program from its inception. From the 1950s onward, he worked as an advisor to NASA, where one of his duties included briefing the Apollo astronauts before their flights to the Moon. Sagan contributed to many of the robotic spacecraft missions that explored the solar system, arranging experiments on many of the expeditions. He conceived the idea of adding an unalterable and universal message on spacecraft destined to leave the solar system that could potentially be understood by any extraterrestrial intelligence that might find it. Sagan assembled the first physical message that was sent into space: a gold-anodized plaque, attached to the space probe Pioneer 10, launched in 1972. Pioneer 11, also carrying another copy of the plaque, was launched the following year. He continued to refine his designs; the most elaborate message he helped to develop and assemble was the Voyager Golden Record that was sent out with the Voyager space probes in 1977. Sagan often challenged the decisions to fund the Space Shuttle and Space Station at the expense of further robotic missions.

Sagan taught a course on critical thinking at Cornell University until he died in 1996 from pneumonia, a few months after finding that he was in remission of myelodysplastic syndrome.

Scientific achievements

Sagan's contributions were central to the discovery of the high surface temperatures of the planet Venus. In the early 1960s no one knew for certain the basic conditions of that planet's surface, and Sagan listed the possibilities in a report later depicted for popularization in a Time-Life book, ''Planets''. His own view was that Venus was dry and very hot as opposed to the balmy paradise others had imagined. He had investigated radio emissions from Venus and concluded that there was a surface temperature of . As a visiting scientist to NASA's Jet Propulsion Laboratory, he contributed to the first Mariner missions to Venus, working on the design and management of the project. Mariner 2 confirmed his conclusions on the surface conditions of Venus in 1962.

Sagan was among the first to hypothesize that Saturn's moon Titan might possess oceans of liquid compounds on its surface and that Jupiter's moon Europa might possess subsurface oceans of water. This would make Europa potentially habitable for life. Europa's subsurface ocean of water was later indirectly confirmed by the spacecraft Galileo. Sagan also helped solve the mystery of the reddish haze seen on Titan, revealing that it is composed of complex organic molecules constantly raining down onto the moon's surface.

He further contributed insights regarding the atmospheres of Venus and Jupiter as well as seasonal changes on Mars. Sagan established that the atmosphere of Venus is extremely hot and dense with pressures increasing steadily all the way down to the surface. He also perceived global warming as a growing, man-made danger and likened it to the natural development of Venus into a hot, life-hostile planet through a kind of runaway greenhouse effect. Sagan and his Cornell colleague Edwin Ernest Salpeter speculated about life in Jupiter's clouds, given the planet's dense atmospheric composition rich in organic molecules. He studied the observed color variations on Mars' surface and concluded that they were not seasonal or vegetational changes as most believed but shifts in surface dust caused by windstorms.

Sagan is best known, however, for his research on the possibilities of extraterrestrial life, including experimental demonstration of the production of amino acids from basic chemicals by radiation.

He is also the 1994 recipient of the Public Welfare Medal, the highest award of the National Academy of Sciences for "distinguished contributions in the application of science to the public welfare." He was denied membership in the Academy, reportedly because his media activities made him unpopular with many other scientists.

Sagan's ability to convey his ideas allowed many people to better understand the cosmos — simultaneously emphasizing the value and worthiness of the human race, and the relative insignificance of the Earth in comparison to the universe. He delivered the 1977 series of Royal Institution Christmas Lectures in London. He hosted and, with Ann Druyan, co-wrote and co-produced the highly popular thirteen-part PBS television series ''Cosmos: A Personal Voyage'' modeled on Jacob Bronowski's ''The Ascent of Man''.

Sagan was a proponent of the search for extraterrestrial life. He urged the scientific community to listen with radio telescopes for signals from intelligent extraterrestrial life-forms. So persuasive was he that by 1982 he was able to get a petition advocating SETI published in the journal ''Science'' and signed by 70 scientists including seven Nobel Prize winners. This was a tremendous turnaround in the respectability of this controversial field. Sagan also helped Dr. Frank Drake write the Arecibo message, a radio message beamed into space from the Arecibo radio telescope on November 16, 1974, aimed at informing extraterrestrials about Earth.

Sagan was chief technology officer of the professional planetary research journal ''Icarus'' for twelve years. He co-founded the ''Planetary Society'', the largest space-interest group in the world, with over 100,000 members in more than 149 countries, and was a member of the SETI Institute Board of Trustees. Sagan served as Chairman of the Division for Planetary Science of the American Astronomical Society, as President of the Planetology Section of the American Geophysical Union, and as Chairman of the Astronomy Section of the American Association for the Advancement of Science.

At the height of the Cold War, Sagan became involved in public awareness efforts for the effects of nuclear war when a mathematical climate model suggested that a substantial nuclear exchange could upset the delicate balance of life on Earth. He was one of five authors — the "S" of the "TTAPS" report as the research paper came to be known. He eventually co-authored the scientific paper hypothesizing a global nuclear winter following nuclear war. He also co-authored the book ''A Path Where No Man Thought: Nuclear Winter and the End of the Arms Race'', a comprehensive examination of the phenomenon of nuclear winter.

''Cosmos'' covered a wide range of scientific subjects including the origin of life and a perspective of our place in the universe. The series was first broadcast by the Public Broadcasting Service in 1980, winning an Emmy and a Peabody Award. It has been broadcast in more than 60 countries and seen by over 500 million people, making it the most widely watched PBS program in history. In addition, ''Time'' magazine ran a cover story about Sagan soon after the show broadcast, referring to him as "creator, chief writer and host-narrator of the new public television series Cosmos, [and] takes the controls of his fantasy spaceship."

Sagan also wrote books to popularize science, such as ''Cosmos'', which reflected and expanded upon some of the themes of ''A Personal Voyage'', and became the best-selling science book ever published in English; ''The Dragons of Eden: Speculations on the Evolution of Human Intelligence'', which won a Pulitzer Prize; and ''Broca's Brain: Reflections on the Romance of Science''. Sagan also wrote the best-selling science fiction novel ''Contact'' in 1985, based on a film treatment he wrote with his wife in 1979, but he did not live to see the book's 1997 motion picture adaptation, which starred Jodie Foster and won the 1998 Hugo Award for Best Dramatic Adaption.

thumb|left|Pale Blue Dot: Earth is a bright pixel when photographed from "Voyager 1" six billion kilometers out (past Pluto). Sagan encouraged NASA to generate this image. He wrote a sequel to ''Cosmos,'' ''Pale Blue Dot: A Vision of the Human Future in Space'', which was selected as a notable book of 1995 by ''The New York Times''. He appeared on PBS' Charlie Rose program in January 1995. Sagan also wrote an introduction for the bestselling book by Stephen Hawking, ''A Brief History of Time''. Sagan was also known for his popularization of science, his efforts to increase scientific understanding among the general public, and his positions in favor of scientific skepticism and against pseudoscience, such as his debunking of the Betty and Barney Hill abduction. To mark the tenth anniversary of Sagan's passing, David Morrison, a former student of Sagan, recalled "Sagan's immense contributions to planetary research, the public understanding of science, and the skeptical movement" in ''Skeptical Inquirer''.

Sagan hypothesized in January 1991 that enough smoke from the 1991 Kuwaiti oil fires "might get so high as to disrupt agriculture in much of South Asia ..." He later conceded in ''The Demon-Haunted World'' that this prediction did not turn out to be correct: "it ''was'' pitch black at noon and temperatures dropped 4°–6°C over the Persian Gulf, but not much smoke reached stratospheric altitudes and Asia was spared." A 2007 study noted that modern computer models have been applied to the Kuwait oil fires, finding that individual smoke plumes are not able to loft smoke into the stratosphere, but that smoke from fires covering a large area, like some forest fires or the burning of cities that would be expected to follow a nuclear strike, would loft significant amounts of smoke into the stratosphere.

In his later years Sagan advocated the creation of an organized search for near Earth objects that might impact the Earth. When others suggested creating large nuclear bombs that could be used to alter the orbit of a NEO that was predicted to hit the Earth, Sagan proposed the Deflection Dilemma: If we create the ability to deflect an asteroid away from the Earth, then we also create the ability to deflect an asteroid towards the Earth — providing an evil power with a true doomsday bomb.

Billions and billions

From ''Cosmos'' and his frequent appearances on ''The Tonight Show Starring Johnny Carson'', Sagan became associated with the catchphrase "billions and billions". Sagan stated that he never actually used the phrase in the ''Cosmos'' series. The closest that he ever came was in the book ''Cosmos'', where he talked of "billions ''upon'' billions": }}

However, his frequent use of the word ''billions'', and distinctive delivery emphasizing the "b" (which he did intentionally, in place of more cumbersome alternatives such as "billions with a 'b'", in order to distinguish the word from "millions" in viewers' minds), made him a favorite target of comic performers, including Johnny Carson, Gary Kroeger, Mike Myers, Bronson Pinchot, Penn Jillette, Harry Shearer, and others. Frank Zappa satirized the line in the song "Be In My Video", noting as well "atomic light". Sagan took this all in good humor, and his final book was entitled ''Billions and Billions'' which opened with a tongue-in-cheek discussion of this catchphrase, observing that Carson himself was an amateur astronomer and that Carson's comic caricature often included real science.

The popular perception of his characterization of large cosmic quantities continued to be a sense of wonderment at the vastness of space and time, as in his phrase "The total number of stars in the Universe is larger than all the grains of sand on all the beaches of the planet Earth." However, this famous saying was widely misunderstood, as he was in fact referring to the world being at a "critical branch point in history" as in the following quote from ''Cosmos: A Personal Voyage'', Episode 8: "Journeys in Space and Time":

"Those worlds in space are as countless as all the grains of sand on all the beaches of the earth. Each of those worlds is as real as ours and every one of them is a succession of incidents, events, occurrences which influence its future. Countless worlds, numberless moments, an immensity of space and time. And our small planet at this moment, here we face a critical branch point in history: what we do with our world, right now, will propagate down through the centuries and powerfully affect the destiny of our descendants. It is well within our power to destroy our civilization and perhaps our species as well."

Sagan units

As a humorous tribute to him, a ''sagan'' has been defined as a unit of measurement equal to at least four billion, since the lower bound of a number conforming to the constraint of ''billions and billions'' must be two billion plus two billion.

Social concerns

Sagan believed that the Drake equation, on substitution of reasonable estimates, suggested that a large number of extraterrestrial civilizations would form, but that the lack of evidence of such civilizations highlighted by the Fermi paradox suggests technological civilizations tend to destroy themselves rather quickly. This stimulated his interest in identifying and publicizing ways that humanity could destroy itself, with the hope of avoiding such a cataclysm and eventually becoming a spacefaring species. Sagan's deep concern regarding the potential destruction of human civilization in a nuclear holocaust was conveyed in a memorable cinematic sequence in the final episode of ''Cosmos'', called "Who Speaks for Earth?" Sagan had already resigned from the Air Force Scientific Advisory Board and voluntarily surrendered his top secret clearance in protest over the Vietnam War. Following his marriage to his third wife (novelist Ann Druyan) in June 1981, Sagan became more politically active — particularly in opposing escalation of the nuclear arms race under President Ronald Reagan.

In March 1983, Reagan announced the Strategic Defense Initiative — a multi-billion dollar project to develop a comprehensive defense against attack by nuclear missiles, which was quickly dubbed the "Star Wars" program. Sagan spoke out against the project, arguing that it was technically impossible to develop a system with the level of perfection required, and far more expensive to build than for an enemy to defeat through decoys and other means — and that its construction would seriously destabilize the nuclear balance between the United States and the Soviet Union, making further progress toward nuclear disarmament impossible.

When Soviet leader Mikhail Gorbachev declared a unilateral moratorium on the testing of nuclear weapons, which would begin on August 6, 1985 — the 40th anniversary of the atomic bombing of Hiroshima — the Reagan administration dismissed the dramatic move as nothing more than propaganda, and refused to follow suit. In response, American anti-nuclear and peace activists staged a series of protest actions at the Nevada Test Site, beginning on Easter Sunday in 1986 and continuing through 1987. Hundreds of people were arrested, including Sagan, who was arrested on two separate occasions as he climbed over a chain-link fence at the test site.

Personal life and beliefs

Sagan was married three times — in 1957, to biologist Lynn Margulis, mother of Dorion Sagan and Jeremy Sagan; in 1968, to artist Linda Salzman, mother of Nick Sagan; and in 1981, to author Ann Druyan, mother of Alexandra Rachel (Sasha) Sagan and Samuel Democritus Sagan. His marriage to Druyan continued until his death in 1996.

Isaac Asimov described Sagan as one of only two people he ever met whose intellect surpassed his own. The other, he claimed, was the computer scientist and artificial intelligence expert Marvin Minsky.

Sagan wrote frequently about religion and the relationship between religion and science, expressing his skepticism about the conventional conceptualization of God as a sapient being. For example:

Some people think God is an outsized, light-skinned male with a long white beard, sitting on a throne somewhere up there in the sky, busily tallying the fall of every sparrow. Others — for example Baruch Spinoza and Albert Einstein — considered God to be essentially the sum total of the physical laws which describe the universe. I do not know of any compelling evidence for anthropomorphic patriarchs controlling human destiny from some hidden celestial vantage point, but it would be madness to deny the existence of physical laws.

In another description of his view of God, Sagan emphatically writes:

The idea that God is an oversized white male with a flowing beard who sits in the sky and tallies the fall of every sparrow is ludicrous. But if by God one means the set of physical laws that govern the universe, then clearly there is such a God. This God is emotionally unsatisfying... it does not make much sense to pray to the law of gravity.

Despite his criticism of religion, Sagan denied that he was an atheist, saying "An atheist has to know a lot more than I know. An atheist is someone who knows there is no god. By some definitions atheism is very stupid." In reply to a question in 1996 about his religious beliefs, Sagan answered, "I'm agnostic." Sagan maintained that the idea of a creator of the universe was difficult to prove or disprove and that the only conceivable scientific discovery that could challenge it would be an infinitely old universe. According to his last wife, Ann Druyan, he was not a believer: }}

In 2006, Ann Druyan edited Sagan's 1985 Glasgow ''Gifford Lectures in Natural Theology'' into a book, ''The Varieties of Scientific Experience: A Personal View of the Search for God'', in which he elaborates on his views of divinity in the natural world. Sagan is also widely regarded as a freethinker or skeptic; one of his most famous quotations, in ''Cosmos'', was, "Extraordinary claims require extraordinary evidence" (called the "Sagan Standard" by some). This was based on a nearly identical statement by fellow founder of the Committee for the Scientific Investigation of Claims of the Paranormal, Marcello Truzzi, "An extraordinary claim requires extraordinary proof." This idea originated with Pierre-Simon Laplace (1749–1827), a French mathematician and astronomer who said, "The weight of evidence for an extraordinary claim must be proportioned to its strangeness."

Late in his life, Sagan's books elaborated on his skeptical, naturalistic view of the world. In ''The Demon-Haunted World: Science as a Candle in the Dark'', he presented tools for testing arguments and detecting fallacious or fraudulent ones, essentially advocating wide use of critical thinking and the scientific method. The compilation ''Billions and Billions: Thoughts on Life and Death at the Brink of the Millennium'', published in 1997 after Sagan's death, contains essays written by Sagan, such as his views on abortion, and his widow Ann Druyan's account of his death as a skeptic, agnostic, and freethinker.

Sagan warned against humans' tendency towards anthropocentrism. He was the faculty adviser for the Cornell Students for the Ethical Treatment of Animals. In the ''Cosmos'' chapter "Blues For a Red Planet", Sagan wrote, "If there is life on Mars, I believe we should do nothing with Mars. Mars then belongs to the Martians, even if the Martians are only microbes."

Sagan was a user and advocate of marijuana. Under the pseudonym "Mr. X", he contributed an essay about smoking cannabis to the 1971 book ''Marihuana Reconsidered''. The essay explained that marijuana use had helped to inspire some of Sagan's works and enhance sensual and intellectual experiences. After Sagan's death, his friend Lester Grinspoon disclosed this information to Sagan's biographer, Keay Davidson. The publishing of the biography, ''Carl Sagan: A Life'', in 1999 brought media attention to this aspect of Sagan's life. Not long after his death, widow Ann Druyan had gone on to preside over the board of directors of NORML, a foundation dedicated to reforming cannabis laws.

In 1994, engineers at Apple Computer code-named the Power Macintosh 7100 "Carl Sagan" in the hope that Apple would make "billions and billions" with the sale of the PowerMac 7100. The name was only used internally, but Sagan was concerned that it would become a product endorsement and sent Apple a cease and desist letter. Apple complied, but engineers retaliated by changing the internal codename to "BHA" for "Butt-Head Astronomer". Sagan then sued Apple for libel, a form of defamation, in federal court. The court granted Apple's motion to dismiss Sagan's claims and opined in dicta that a reader aware of the context would understand Apple was "clearly attempting to retaliate in a humorous and satirical way", and that "It strains reason to conclude that Defendant was attempting to criticize Plaintiff's reputation or competency as an astronomer. One does not seriously attack the expertise of a scientist using the undefined phrase 'butt-head'." Sagan then sued for Apple's original use of his name and likeness, but again lost. Sagan appealed the ruling. In November 1995, an out of court settlement was reached and Apple's office of trademarks and patents released a conciliatory statement that "Apple has always had great respect for Dr. Sagan. It was never Apple's intention to cause Dr. Sagan or his family any embarrassment or concern."

Sagan briefly served as an adviser on Stanley Kubrick's film ''2001: A Space Odyssey''. Sagan proposed that the film would suggest, rather than depict, extraterrestrial superintelligence.

Sagan and UFOs

Sagan had some interest in UFO reports from at least 1964 when he had several conversations on the subject with Jacques Vallee. Though quite skeptical of any extraordinary answer to the UFO question, Sagan thought scientists should study the phenomenon, at least because there was widespread public interest in UFO reports.

Stuart Appelle notes that Sagan "wrote frequently on what he perceived as the logical and empirical fallacies regarding UFOs and the abduction experience. Sagan rejected an extraterrestrial explanation for the phenomenon but felt there were both empirical and pedagogical benefits for examining UFO reports and that the subject was, therefore, a legitimate topic of study."

In 1966, Sagan was a member of the Ad Hoc Committee to Review Project Blue Book, the U.S. Air Force's UFO investigation project. The committee concluded Blue Book had been lacking as a scientific study, and recommended a university-based project to give the UFO phenomenon closer scientific scrutiny. The result was the Condon Committee (1966–1968), led by physicist Edward Condon, and in their final report they formally concluded that UFOs, regardless of what any of them actually were, did not behave in a manner consistent with a threat to national security.

Ron Westrum writes that "The high point of Sagan's treatment of the UFO question was the AAAS's symposium in 1969. A wide range of educated opinions on the subject were offered by participants, including not only proponents such as James McDonald and J. Allen Hynek but also skeptics like astronomers William Hartmann and Donald Menzel. The roster of speakers was balanced, and it is to Sagan's credit that this event was presented in spite of pressure from Edward Condon". With physicist Thornton Page, Sagan edited the lectures and discussions given at the symposium; these were published in 1972 as ''UFOs: A Scientific Debate''. Some of Sagan's many books examine UFOs (as did one episode of ''Cosmos'') and he claimed a religious undercurrent to the phenomenon.

Sagan again revealed his views on interstellar travel in his 1980 ''Cosmos'' series. In one of his last written works, Sagan argued that the chances of extraterrestrial spacecraft visiting Earth are vanishingly small. However, Sagan did think it plausible that Cold War concerns contributed to governments misleading their citizens about UFOs, and that "some UFO reports and analyses, and perhaps voluminous files, have been made inaccessible to the public which pays the bills ... It's time for the files to be declassified and made generally available." He cautioned against jumping to conclusions about suppressed UFO data and stressed that there was no strong evidence that aliens were visiting the Earth either in the past or present.

Death

After a long and difficult fight with myelodysplasia, which included three bone marrow transplants, Sagan died of pneumonia at the age of 62 at the Fred Hutchinson Cancer Research Center in Seattle, Washington, on December 20, 1996. He was buried at Lakeview Cemetery in Ithaca, New York.

Posthumous recognition

The 1997 movie ''Contact'', based on Sagan's novel of the same name and finished after his death, ends with the dedication "For Carl".

In 1997, the Sagan Planet Walk was opened in Ithaca New York. It is a walking scale model of the solar system, extending 1.2 km from the center of The Commons in downtown Ithaca, NY, to the Sciencenter, a hands-on museum. The exhibition was created in memory of Carl Sagan, who was an Ithaca resident and Cornell Professor. Professor Sagan had been a founding member of the museum's advisory board.

The landing site of the unmanned Mars Pathfinder spacecraft was renamed the ''Carl Sagan Memorial Station'' on July 5, 1997.

Sagan's son, Nick Sagan, wrote several episodes in the ''Star Trek'' franchise. In an episode of ''Star Trek: Enterprise'' entitled "Terra Prime", a quick shot is shown of the relic rover Sojourner, part of the Mars Pathfinder mission, placed by a historical marker at Carl Sagan Memorial Station on the Martian surface. The marker displays a quote from Sagan: "Whatever the reason you're on Mars, I'm glad you're there, and I wish I was with you." Sagan's student Steve Squyres led the team that landed the Spirit Rover and Opportunity Rover successfully on Mars in 2004.

Asteroid 2709 Sagan is also named in his honor.

On November 9, 2001, on what would have been Sagan's 67th birthday, the NASA Ames Research Center dedicated the site for the Carl Sagan Center for the Study of Life in the Cosmos. "Carl was an incredible visionary, and now his legacy can be preserved and advanced by a 21st century research and education laboratory committed to enhancing our understanding of life in the universe and furthering the cause of space exploration for all time", said NASA Administrator Daniel Goldin. Ann Druyan was at the Center as it opened its doors on October 22, 2006.

Sagan has at least three awards named in his honor:

The Carl Sagan Memorial Award presented jointly since 1997 by the American Astronomical Society (AAS) and the Planetary Society,

The Carl Sagan Medal for Excellence in Public Communication in Planetary Science presented since 1998 by the American Astronomical Society's Division for Planetary Sciences (AAS/DPS) for outstanding communication by an active planetary scientist to the general public — Carl Sagan was one of the original organizing committee members of the DPS, and

The Carl Sagan Award for Public Understanding of Science presented by the Council of Scientific Society Presidents (CSSP) — Sagan himself was the first recipient of the CSSP award in 1993. In 2006, the Carl Sagan Medal was awarded to astrobiologist and author David Grinspoon, the son of Sagan's friend Lester Grinspoon.

On December 20, 2006, the tenth anniversary of Sagan's death, a blogger, Joel Schlosberg, organized a Carl Sagan "blog-a-thon" to commemorate Sagan's death, and the idea was supported by Nick Sagan. Many members of the blogging community participated.

August 2007 the Independent Investigative Group IIG awarded Sagan posthumously a Lifetime Achievement Award. This honor has also been awarded to Harry Houdini and James Randi.

In 2008, Benn Jordan, also known as "The Flashbulb", released the album ''Pale Blue Dot: A Tribute to Carl Sagan''.

In 2009, clips from Carl Sagan's ''Cosmos'' were used as the basis for ''A Glorious Dawn'', the first video produced for the Symphony of Science, an educational music video production by composer John Boswell. Musician Jack White later released this song as a vinyl single under his record label Third Man Records. Additional clips were used in several followup videos which featured Sagan alongside other noted scientists and proponents of rational thinking, such as Richard Dawkins, Richard Feynman, Brian Greene, Lawrence M. Krauss, Bill Nye, and Neil deGrasse Tyson.

In 2010, the 76th anniversary of Carl Sagan's birth, the second "Carl Sagan Day" was celebrated on November 6.

Awards and honors

Annual Award for Television Excellence — 1981 — The Ohio State University — PBS series ''Cosmos''

Apollo Achievement Award — National Aeronautics and Space Administration

NASA Distinguished Public Service Medal — National Aeronautics and Space Administration (twice)

Emmy — Outstanding Individual Achievement — 1981 — PBS series ''Cosmos''

Emmy — Outstanding Informational Series — 1981 — PBS series ''Cosmos''

Exceptional Scientific Achievement Medal — National Aeronautics and Space Administration

Helen Caldicott Leadership Award — Women's Action for Nuclear Disarmament

Hugo Award — 1981 — ''Cosmos''

Humanist of the Year — 1981 — Awarded by the American Humanist Association

In Praise of Reason Award — 1987 — Committee for the Scientific Investigation of Claims of the Paranormal

Isaac Asimov Award — 1994 — Committee for the Scientific Investigation of Claims of the Paranormal

John F. Kennedy Astronautics Award — American Astronautical Society

John W. Campbell Memorial Award — 1974 — ''Cosmic Connection: An Extraterrestrial Perspective''

Joseph Priestley Award — "For distinguished contributions to the welfare of mankind"

Klumpke-Roberts Award of the Astronomical Society of the Pacific — 1974

Konstantin Tsiolkovsky Medal — Awarded by the Soviet Cosmonauts Federation

Locus Award 1986 — ''Contact''

Lowell Thomas Award — Explorers Club — 75th Anniversary

Masursky Award — American Astronomical Society

Miller Research Fellowship — Miller Institute (1960–1962)

Oersted Medal — 1990 — American Association of Physics Teachers

Peabody Award — 1980 — PBS series ''Cosmos''

Prix Galbert — The international prize of Astronautics

Public Welfare Medal — 1994 — National Academy of Sciences

Pulitzer Prize for General Non-Fiction — 1978 — ''The Dragons of Eden''

SF Chronicle Award — 1998 — ''Contact''

Named the "99th Greatest American" on the June 5, 2005, ''Greatest American'' show on the Discovery Channel

Publications

''Planets'' (LIFE Science Library), Sagan, Carl, Jonathan Norton Leonard and editors of Life, Time, Inc., 1966

''Intelligent Life in the Universe'', I.S. Shklovskii coauthor, Random House, 1966, ISBN 1-892803-02-X, 509 pgs (note: republished in 1998 by Emerson-Adams Press)

''UFOs: A Scientific Debate'', Thornton Page coauthor, Cornell University Press, 1972, 310 pgs

''Communication with Extraterrestrial Intelligence''. MIT Press, 1973, 428 pgs

''Mars and the Mind of Man'', Sagan, Carl, et al., Harper & Row, 1973, 143 pgs

''Cosmic Connection: An Extraterrestrial Perspective'', Jerome Agel coauthor, Anchor Press, 1973, ISBN 0-521-78303-8, 301 pgs

''Other Worlds''. Bantam Books, 1975

''Murmurs of Earth: The Voyager Interstellar Record'', Sagan, Carl, et al., Random House, ISBN 0-394-41047-5, 1978

''The Dragons of Eden: Speculations on the Evolution of Human Intelligence''. Ballantine Books, 1978, ISBN 0-345-34629-7, 288 pgs

''Broca's Brain: Reflections on the Romance of Science''. Ballantine Books, 1979, ISBN 0-345-33689-5, 416 pgs

''Cosmos''. Random house, 1980. Random House New Edition, May 7, 2002, ISBN 0-375-50832-5, 384 pgs

''The Cold and the Dark: The World after Nuclear War'', Sagan, Carl et al., Sidgwick & Jackson, 1985

''Comet'', Ann Druyan coauthor, Ballantine Books, 1985, ISBN 0-345-41222-2, 496 pgs

''Contact''. Simon and Schuster, 1985; Reissued August 1997 by Doubleday Books, ISBN 1-56865-424-3, 352 pgs

''A Path Where No Man Thought: Nuclear Winter and the End of the Arms Race'', Richard Turco coauthor, Random House, 1990, ISBN 0-394-58307-8, 499 pgs

''Shadows of Forgotten Ancestors: A Search for Who We Are'', Ann Druyan coauthor, Ballantine Books, October 1993, ISBN 0-345-38472-5, 528 pgs

''Pale Blue Dot: A Vision of the Human Future in Space''. Random House, November 1994, ISBN 0-679-43841-6, 429 pgs

''The Demon-Haunted World: Science as a Candle in the Dark''. Ballantine Books, March 1996, ISBN 0-345-40946-9, 480 pgs (note: the book was first published and copyrighted in 1995 with an errata slip inserted)

''Billions and Billions: Thoughts on Life and Death at the Brink of the Millennium'', Ann Druyan coauthor, Ballantine Books, June 1997, ISBN 0-345-37918-7, 320 pgs

''The Varieties of Scientific Experience: A Personal View of the Search for God'', Carl Sagan (writer) & Ann Druyan (editor), 1985 Gifford lectures, Penguin Press HC, November 2006, ISBN 1-59420-107-2, 304 pgs

References

Further reading

External links

The Carl Sagan Portal

BBC Radio program "Great Lives" on Carl Sagan's life

A Man whose time Has come — Interview with Carl Sagan by Ian Ridpath, New Scientist 1974 July 4

Carl Sagan Prize for Science Popularization

Carl Sagan Medal for Excellence in Public Communication in Planetary Science, presented by the American Astronomical Society's Division for Planetary Sciences (AAS/DPS)

Carl Sagan Center for the Study of Life in the Universe, SETI Institute

Carl Sagan's Life and Legacy as Scientist, Teacher, and Skeptic, Committee for Skeptical Inquiry

Cosmos — Full Episodes and Clips streaming online for free — Hulu, Cosmos online for free

A Tribute to Carl Sagan: Our Place in the Universe, The Skeptics Society

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Name	Julian Casablancas
Alt	Julian Casablancas
Background	solo_singer
Birth name	Julian Fernando Casablancas
Born	August 23, 1978New York City, New York, United States
Origin	New York City, USA
Spouse	Juliet Joslin(February, 2005-2011)
Instrument	Lead vocals, keyboards, guitar, bass, drums, guitar synthesizer, harmonica
Genre	Indie rock, New Wave, alternative rock, garage rock, post-punk revival, synthpop
Occupation	Singer, songwriter
Years active	1998–present
Label	Cult, Rough Trade, RCA, Sony BMG
Associated acts	The Strokes, Queens of the Stone Age, The Lonely Island, Danger Mouse, N.E.R.D, Santigold
Website
Notable instruments	}}

Julian Fernando Casablancas (born August 23, 1978) is an American singer/songwriter and musician, best known as the lead vocalist and chief songwriter of American rock band The Strokes. Casablancas pursued a solo career during The Strokes' hiatus, releasing the album ''Phrazes for the Young'' on November 3, 2009.

Early life, education, and personal life

Julian Fernando Casablancas was born in New York, New York, to Catalan-American business mogul John Casablancas, the founder of Elite Model Management, and Jeanette Christiansen, a former model and Miss Denmark. His paternal grandfather, Fernando Casablancas, was a well-known textile businessman. His parents divorced and his mother subsequently married painter Sam Adoquei. Adoquei helped shape Casablancas' early musical taste by exposing him to music such as The Doors which was markedly different from the mostly Phil Collins-influenced music he originally listened to.

The first member of The Strokes Casablancas met was Nikolai Fraiture, who attended Lycée Français de New York with him (Fraiture graduated in 1997, Casablancas in 1996). When he was 14, Casablancas' father sent him to Institut Le Rosey, an elite boarding school in Switzerland. It was during Julian's brief stay in Switzerland that he met future Strokes member Albert Hammond, Jr. Casablancas attended The Dwight School with two other future Strokes, Nick Valensi and Fabrizio Moretti. Casablancas never finished school, but continued to take music classes where he says he first enjoyed himself in class.

Julian married The Strokes' former assistant manager, Juliet Casablancas (née Joslin), on February 5, 2005 in New York. The couple have a son named Cal, born in early 2010.

Musical career

Influences

Julian Casablancas' has said that Sam Cooke's "A Change Is Gonna Come" is his favorite song of all time. He has also stated that Frank Sinatra's "Oh! Look at Me Now" as another one of his favorites. In addition, Julian Casablancas has also cited Lou Reed of The Velvet Underground as a major influence on his lyrics and singing style. "The way Lou Reed wrote and sang about drugs and sex, about the people around him — it was so matter-of-fact", Casablancas stated in a Rolling Stone interview, "Reed could be romantic in the way he portrayed these crazy situations, but he was also intensely real. It was poetry and journalism".

Solo work

His first solo album, ''Phrazes for the Young'' (inspired by the Oscar Wilde book "Phrases and Philosophies for the Use of the Young"), was released on November 2 in the UK and November 3, 2009, in the United States. Recorded in Omaha, Nebraska, and Casablancas' home city New York, the album was produced by Jason Lader, with additional production from Bright Eyes' Mike Mogis. The album was strongly influenced by new wave and electronica, with Casablancas utilizing synthesizers for many songs. He discussed his new influences by saying "I would've gone weirder with the music, but I wanted to be smart. I didn't want people to say, 'Okay, this is his weird abstract thing,' and dismiss the album. I worked too hard on it for that to happen...I wanted to be crazy original and bridge the gap between traditional music and modern music."

To celebrate the release, Julian performed a series of shows in October in Los Angeles. Julian then toured with The Sick Six in Europe from November 30, 2009.

Other work

Known to not play much on Strokes recordings, Julian has proven himself an able multi-instrumentalist through guest appearances. He has played a casio guitar and provided backing vocals on "Sick, Sick, Sick" by Queens of the Stone Age, bass guitar and backing vocals on Albert Hammond, Jr.'s "Scared", and the second set of drums on the Strokes' "Evening Sun".

He has also served as inspiration for several other musicians and the painter Elizabeth Peyton. Courtney Love's song "But Julian, I'm a Little Bit Older Than You", from her debut solo album ''America's Sweetheart'' (2004), was written about Julian Casablancas.

In 2008, Julian recorded a song with Santigold (then known as Santogold) and Pharrell of N*E*R*D called "My Drive Thru" for Converse. He also appeared in the advertisement campaign.

In 2009, Julian recorded a song with Andy Samberg, Jorma Taccone, and Akiva Schaffer of The Lonely Island called "Boombox" for their debut album, and was featured in an SNL Digital Short for the same song. He also collaborated with Danger Mouse and Sparklehorse on the song "Little Girl".

Julian performed "I Wish It Was Christmas Today" (based on a ''Saturday Night Live'' skit) on ''Late Night with Jimmy Fallon'' on December 21, 2009.

Julian, along with the Strokes, performed on a cover of Marvin Gaye's Mercy Mercy Me with Joshua Homme on drums and Eddie Vedder on backup vocals. The cover was released in 2006 as the b-side to You Only Live Once.

On April 11, 2011 Julian tweeted that he had: "just finished mastering a Buddy Holly track I recorded...list of other artists involved seems PRIT-ty rad. Stay tuned...". On April 29, 2011 via Twitter, he confirmed that his cover of "Rave On" would be the title track of an upcoming tribute album to Buddy Holly: "6/28 check out BH cover we did of Rave On (or Ray Vaughan as we say) w/ Matt Sweeney and Tommy Brenneck aka Tall Boyz". @Casablancas_J on Twitter.

On June 7, 2011 Azzaro Perfume chose Julian Casablancas to represent its new men's fragrance, Decibel, dB and to compose the music for the advert.

On July 6, 2011 Julian confirmed via Twitter that he composed a song for the Azzaro Perfume commercial ad stating: "Finished mixing a new song "I Like The Night" for Azzaro / Decibel. Stay tuned to listen..."

Discography

Studio albums

Title

Details

Peak chart positions

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''Phrazes for the Young''

* Release date: October 30, 2009

* Label: RCA Records

Compact disc>CD, music download

35

#

10

12

30

34

49

19

Singles

Year	Single	Peak positions	Album
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	! scope="row"	48
"I Wish It Was Christmas Today"	—

References

External links

Category:1978 births Category:Living people Category:Roseens Category:American male singers Category:American rock singers Category:American singer-songwriters Category:American people of Catalan descent Category:Musicians from New York City Category:The Strokes members Category:Lycée Français de New York alumni

cs:Julian Casablancas da:Julian Casablancas de:Julian Casablancas es:Julian Casablancas fr:Julian Casablancas it:Julian Casablancas he:ג'וליאן קזבלנקס nl:Julian Casablancas ja:ジュリアン・カサブランカス no:Julian Casablancas pl:Julian Casablancas pt:Julian Casablancas ru:Касабланкас, Джулиан fi:Julian Casablancas sv:Julian Casablancas