HOYLE, FRED

(b. Gilstead, Bingley, West Yorkshire, United Kingdom, 24 June 1915; d. Bournemouth, Dorset, United Kingdom, 20 August 2001),

cosmology, nuclear astrophysics, astrobiology, science fiction, science journalism.

Hoyle was an outstanding British cosmologist and astrophysicist whose penchant for controversial theories meant he was seldom out of the public eye between 1950 and 1980. Uniquely he combined a sharp and creative scientific intellect with superb communication skills, which brought his controversial ideas to a wide audience. Publicly, Hoyle was best known as the leading proponent of the steady state theory of cosmology. His greatest achievement was showing how the chemical elements heavier than helium have been created by thermonuclear reactions inside stars. In the latter part of his career he moved away from mainstream astronomy, courting controversy with his enthusiasm for panspermia, or the seeding of life on Earth from space.

Family and Education . Fred Hoyle’s father was a wool merchant, and his mother a talented pianist who had trained as a teacher. After Hoyle’s birth, his father enlisted as a machine gunner in the army, and spent three years (1915–1918) in the valley of the Somme, France, fighting on the front line. He returned in 1919, physically unscathed but mentally shattered, with a deep contempt of politics, public life, and the establishment, a trait that his son adopted. In the 1920s Hoyle’s parents had very little money. He learned arithmetic and reading from his mother: he did not regularly attend school until he was about eight years of age. Evidently he was a star pupil at the rural elementary school he attended because he was the only child to win a place at Bingley Grammar School, which awarded him a clothing allowance. His parents strongly encouraged his schooling, allowing him to perform dangerous chemical experiments at home and rewarding him with a telescope when they noticed his strong interest in the stars.

Hoyle’s performance at the grammar school secured him a place at Emmanuel College, Cambridge, where he read mathematics. From the moment he arrived in Cambridge, in October 1933, Hoyle was an outsider. His impoverished background, old clothes, and marked regional accent set him apart from the polished members of the aristocracy and the privileged elite from England’s major private schools. He immersed himself in his studies, with stunning success. The university graded him first class at the end of his freshman year. He skipped the second-year curriculum entirely, and moved onto graduate-level courses for his third year. He graduated as the top-ranked applied mathematician of his year.

His undergraduate achievement assured him a place as a research student in the Cavendish Laboratory, the birthplace of nuclear physics, where the electron, isotopes, and the neutron had been discovered, resulting in a string of Nobel Prizes. Hoyle’s first supervisor was the German-Jewish émigré Rudolf Peierls and, second, Paul Dirac (Nobel Prize in Physics 1933), then at the height of his fame as a founder of modern quantum theory. In 1938, as a research student, Hoyle wrote a paper on the theory of beta decay (a radioactive process in which a neutron decays to a proton and an electron). This won him the prestigious Smith’s Prize, an award at Cambridge for the best performance by a research student in mathematics. The following year two papers on quantum electrodynamics secured him two fellowships, one at St. John’s College, Cambridge, and the other from a private foundation. At this stage, with World War II just weeks away, Hoyle decided to switch his interest to astronomy, instead of nuclear physics, which he felt was then already on the path to the production of weapons of mass destruction.

Wartime Research . His first collaborator in astrophysics was Raymond Lyttleton, with whom he wrote papers on the accretion of interstellar matter by stars. The Royal Astronomical Society, to which they submitted their papers, was reluctant to publish what they felt were speculative hypotheses, which led to the first clash between the youthful Hoyle and the British research establishment.

In 1940 Hoyle and Lyttleton were both drafted into defense research. Despite physical separation, they kept up their collaboration, mainly through a voluminous correspondence in which Lyttleton took every opportunity to complain to the then-impressionable Hoyle about the incompetence of the British government and the obstacles to publication of their papers. Lyttleton communicated a disdain for officialdom, conservative procedures, and the British class structure that would remain with Hoyle for the rest of his life.

The Admiralty (the government department responsible for the Royal Navy) recruited Hoyle for theoretical research on radar. Major ships had defensive radar, which could determine the direction and distance of an attacking aircraft, but not its height. This meant that fighter aircraft were virtually flying blind when a ship was threatened. A theoretical analysis enabled Hoyle to devise a method by which a radar operator could deduce the altitude by studying the way in which the radar echo strengthened and faded as an attacking aircraft closed in. His ingenious solution undoubtedly aided the Royal Navy in the early sea battles in the eastern Mediterranean Sea, but, for reasons of secrecy, Hoyle never received public recognition for this significant contribution to Britain’s wartime defense.

In 1944 Hoyle participated in a conference held in Washington, D.C., at the Naval Research Laboratory. He took the opportunity to visit three of the most distinguished astronomers in the United States: Henry Norris Russell at Princeton, Harlow Shapley at Harvard, and Walter Baade of the Mount Wilson Observatory, Pasadena. These encounters, which marked the beginning of Hoyle’s long and productive relationship with colleagues in the United States, would profoundly guide his research program immediately after the war.

As director of the theory division at the radar establishment, Hoyle recruited in June 1942 a deputy, Hermann Bondi, another Cambridge mathematician. On Bondi’s advice, in October 1942 Hoyle brought in Thomas Gold, a Cambridge graduate in engineering science. Bondi and Gold were originally from Vienna, Austria, but they left Austria shortly before the Anschluss.

Bondi, Gold, and Hoyle shared a small rented house close to their place of work. They spent their evenings and weekends debating problems in astrophysics. Hoyle directed Bondi toward the accretion work he had done with Lyttleton. Bondi improved the theory considerably, which led to his winning a research fellowship at Trinity College. Hoyle and Bondi published the work in 1947. For many years astrophysicists ignored their ideas until, in the 1970s, it was discovered that there are circumstances under which compact neutron stars can accrete interstellar gas, which creates x-rays. So their 1947 accretion paper is now widely cited, for reasons that were unimaginable when they published the theory.

Cosmology . All three returned to Cambridge in 1945. Hoyle and Gold had jobs as university lecturers, but no workplace in the faculty of mathematics. Consequently all three worked in practice in Bondi’s spacious rooms in Trinity College. In 1947 they started to work together on cosmology, then a very difficult subject, which they had previously ignored. There were problems with the observations: from the expansion of the universe, Edwin Hubble gave 1.8 billion years as the Hubble time, about half the age of Earth. This had led theoretical astronomers to propose several conflicting models of the universe, none of which could be tested using the telescopes of the time. The expansion of the universe appeared to imply a singular origin at some point in the past.

In 1942 the cosmologist George Gamow spoke in Washington in favor of an explosive origin for the universe. Four years later he suggested that a primordial explosion in the young universe could have made the chemical elements by nuclear processes. The Cambridge trio were not, however, aware of this work. Baade had privately suggested to Hoyle that the chemical elements were made in red giant stars, an idea he worked on alone from 1946 (Bondi and Gold were not well versed in nuclear physics).

In 1947 Gold suggested that the universe could have had no beginning and would have no end: it had always existed. Bondi and Hoyle seized on this idea, known as steady state cosmology, immediately. Hoyle always felt that an important question in cosmology is whether or not there is a relationship between the structure of the universe and the laws of physics. Dirac, in 1938, had argued that a universe in motion requires laws of physics that change with time. Scientific ideas about the creation of matter in the universe can be traced back to the 1880s. In the steady state cosmology the important feature was that the voids left by the expansion of the universe would be filled by the spontaneous creation of matter, so that the physical appearance of the universe and the laws of physics would be the same for all observers and all epochs. This continuous creation aspect greatly appealed to all three of them.

Unlike the physicists who had earlier toyed with matter creation, Hoyle immediately felt the need for finding a mechanism to create the matter, and he quickly settled on a field theory. The journal Nature, and then the Physical Society, rejected his paper on the mechanism. By the time the Royal Astronomical Society eventually published his paper, Bondi and Gold had already published a rival paper on the steady state theory. All three pressed the merits of the theory at scientific conferences. However, in the competition between the steady state theory, and what Hoyle termed the big bang universe, it was clear from the outset that most of the astronomical community and its leaders preferred the big bang. Outside Britain, the steady state theory received no attention.

BBC radio provided Hoyle with a platform for the promotion of continuous creation. On 28 March 1949, he gave a 20-minute talk about his new cosmological ideas. For the first time he referred to the explosive origin of the universe as a big bang. Early the following year the BBC commissioned five lengthy talks from Hoyle, and this gave him another opportunity to bring his ideas to a wide public. The talks were published as a best-selling book, The Nature of the Universe. Almost overnight, it seemed, Hoyle had become the most famous astronomer in Britain. Simultaneously, he courted controversy by adding to his hypothesis a naive theological interpretation, critical of Christian belief.

By the 1950s, the emerging discipline of radio astronomy provided a tool for testing the rival theories of cosmology. In the big bang picture the distant parts of the universe will not have exactly the same properties as the local universe because they are being seen at an earlier epoch, when the universe was denser. In the steady state universe no evolution is discernable. Cambridge radio astronomers, led by Martin Ryle, made an early claim to have detected evolution. Their original results were deeply flawed, and naturally Hoyle rejected them. Disagreements between Hoyle and Ryle soon became aired in public, with both sides using the mass media to convey their findings. Ultimately Ryle’s observations did show evidence for evolution. Then, in 1965, Arno Penzias and Robert Wilson announced the serendipitous discovery of the cosmic microwave background radiation, immediately interpreted as fossil evidence for a hot dense phase, or big bang, in the early universe. From that point Hoyle’s steady state hypothesis was doomed, although he never accepted the confident statements of his rivals in cosmology.

Origin of the Chemical Elements . When Hoyle had arrived in Cambridge, the theoretical astronomer Arthur S. Eddington was at the height of his career, a world expert on the structure and evolution of stars; by observations made at a total eclipse in 1919, Eddington had confirmed a prediction of Einstein’s general theory of relativity. Hoyle always looked up to Eddington, whose example he followed in working on the composition of stars. Once the nuclear sources of stellar energy were understood, Hoyle reformulated Eddington’s early work on homogeneous stars, discovering that red giant stars must have an inhomogeneous structure. Hoyle was a pioneer in the use of digital computers for modeling stars. He produced the first models of stars that are primarily composed of hydrogen. He visited Princeton in 1954, where he and Martin Schwarzschild gave the first complete account of the evolution of a low-mass star once it has exhausted the hydrogen fuel in the nuclear core.

Hoyle’s greatest achievement, a theory of nucleosynthesis in stars, also began in the immediate postwar period. Working alone, Hoyle found the nuclear chain reaction responsible for building the chemical elements from carbon to iron at a temperature of 3 billion degrees (3 × 10⁹ K) in the interiors of red giant stars. He concluded that practically all of the chemical elements had been synthesized in stellar interiors, under a variety of physical conditions. At this point he was still unable to account for the presence of carbon, his starting point.

On his visit in 1953 to the Kellogg Radiation Laboratory at the California Institute of Technology (Caltech), Hoyle solved the carbon puzzle in a spectacular fashion. In effect he discovered the physical mechanism that would allow three helium nuclei to coalesce and form a stable carbon nucleus. For this to happen, Hoyle predicted that the carbon nucleus must have an excited energy state above its normal ground state. The Kellogg lab had the equipment to test this hypothesis, and indeed they found an excited state at precisely the energy level predicted by Hoyle. This result, predicted purely from astrophysics, greatly impressed the nuclear physics community, who now believed in nucleosynthesis in stars.

During his annual visits to Caltech, Hoyle collaborated with the astrophysicists Margaret and Geoffrey Burbidge, and the experimental nuclear physicist William Fowler, on the origin of the chemical elements. This led to Hoyle’s greatest masterpiece, a lengthy paper published in 1957 in Reviews of Modern Physics. This paper, authored by the Burbidges, Fowler, and Hoyle, is universally referred to as B2FH by astrophysicists. It is Hoyle’s most widely quoted paper, in which an account is given of the origin and abundance of all the isotopes apart from those of the five lightest elements. The basic physical mechanisms for forging the chemical elements in stars remain essentially unchanged. Hoyle’s contribution to the paper was huge: it was he who carried out most of the calculations in nuclear physics. Many commentators were deeply shocked when the 1983 Nobel Prize for Physics was awarded to Fowler and Subrahmanyan Chandrasekhar for contributions to nucleosynthesis and stellar structure, respectively, areas in which Hoyle’s achievement exceeded that of the two laureates.

Interstellar Matter . Hoyle’s early work on accretion led to an interest in interstellar matter that lasted throughout his career. An early paper attributed climate change and ice ages to the cooling effects of the Sun passing through an interstellar dust cloud, which became the theme of his best work of science fiction, The Black Cloud (1957). He speculated thirty years before anyone else that hydrogen molecules are an important source of cooling in interstellar clouds. During the 1950s he modeled the fragmentation of gas clouds into galaxies and stars. He filled the gaps in his knowledge in a highly intuitive manner that turned out to be correct.

With his research student N. Chandra Wickramasinghe, Hoyle investigated the composition of interstellar grains from 1960. They suggested that carbon is a major constituent of grains. Data from space observatories in the late 1970s enabled them to explain that complex hydrocarbons must be the main ingredients. They then extended the scope of their investigations, claiming that very complex organic compounds are present in comets and interstellar matter.

Hoyle believed strongly that life could not have originated spontaneously on Earth. He frequently asserted that the probability of life self-assembling from inanimate material is too small. He and Wickramasinghe speculated that life on Earth had arrived as bacteria borne by comets. This assertion was ridiculed by molecular biologists; professional astronomers too began to ignore Hoyle’s research from the late 1970s onward. Nevertheless, some of his ideas, such as the suggestion that comets delivered inanimate organic material and water to the early Earth, are now regarded as plausible by astrobiologists. Hoyle, with Lyttleton, was the first to suggest (1939) that astronomical events, including cometary impacts, could cause ecological disaster on Earth. They speculated that the boundary between the Cretaceous and Tertiary periods in the fossil record was due to species extinctions triggered by a cometary impact 65 million years ago.

Hoyle’s approach to theoretical research differed markedly from the masters who preceded him. Whereas they had spent a lifetime in just one or two areas (Eddington working on stellar evolution, for example), Hoyle regarded the entire celestial realm as being within the compass of his inquiries. While he intrigued and entertained the public with a copious stream of new, but sometimes weakly supported, ideas, some professionals felt he was the noisy upstart who had invaded their special areas of inquiry.

Administration . In the three decades 1945–1975 Hoyle transformed theoretical astronomy and cosmology in Britain. Wartime defense research had drained the young talent from Britain’s universities. Astronomy in the United States was far ahead; the 200-inch Palomar telescope had commenced observations in 1948. Britain had nothing to compete with it. Hoyle led a despondent research community of applied mathematicians away from the fading traditions of dynamical and positional astronomy. He directed his research students toward the richness and diversity of the new astrophysics that began to emerge in the 1960s. Unfortunately he treated his Cambridge colleagues with disdain and failed to develop a fruitful relationship with the astronomically minded members of the faculties of mathematics and physics. Instead he concentrated on his own research students, Stephen Hawking among them, and his rich collaborations with colleagues in the United States, particularly those in Pasadena, California. By the mid-1960s he assembled a world-class team of theorists in Cambridge, which once again became the greatest school of astronomy in Europe.

From 1967 to 1972 Hoyle directed the new Institute of Theoretical Astronomy in Cambridge. He had been instrumental in founding it, securing its initial funding, and obtaining the most powerful computer in the world for his theorists. He ran a vigorous program of summer visiting fellowships, which were used to bring the brightest theorists from North America to the institute. This annual infusion played a significant part in developing theoretical astronomy in the United Kingdom, at a time when British observational astronomers still tended to regard their North American colleagues as competitors rather than collaborators.

Although Hoyle generally found committee work repellent, he served with distinction on the U.K. Science Research Council from 1967 to 1972. As chairman of its astronomy, space, and radio board he was active in the assessment of the astronomical facilities in the Southern Hemisphere, which led to the creation of the 150-inch Anglo-Australian Telescope. He served as president of the Royal Astronomical Society from 1971 to 1973.

In 1972 he made a dramatic resignation from his professorship at Cambridge, citing as the reason for his departure irreconcilable differences of opinion with the university on the future management of astronomy at Cambridge. He felt that political moves by his Cambridge rivals had made his position untenable.

Hoyle married, in 1939, Barbara Clark, who intensely supported him for more than sixty years during a close and happy marriage. She served as personal assistant, diary secretary, and literary agent, as well as raising their two children, Geoffrey and Elizabeth, and running an open house for graduate students and academic visitors. Hoyle’s interests, apart from research and family, extended to hill climbing and classical music. His scientific output encompassed almost four hundred papers. His corpus extended to six research monographs, twenty-seven textbooks and popular science books, and fifteen science-fiction works.

He received many honors, among them Fellow of the Royal Society (1957), associate member of the U.S. National Academy of Sciences (1969), knighted for services to astronomy by Queen Elizabeth II (1972), and gold medalist of the Royal Astronomical Society (1968). The Royal Swedish Academy of Sciences made him joint recipient of the 1997 Crafoord Prize, equal in monetary value to the Nobel Prize.

BIBLIOGRAPHY

A complete bibliography is available on request from the library of the Royal Society, London. A bibliography of papers is given at http://www.fredhoyle.com. Most of his research papers are available to download at Harvard College Observatory by searching under his name at http://adsabs.harvard.edu/abstract_service.html.

WORKS BY HOYLE

“The Synthesis of the Elements from Hydrogen. ” Monthly Notices of the Royal Astronomical Society 106 (1946): 343–383. First paper on the origin of the elements.

“A New Model for the Expanding Universe.” Monthly Notices of the Royal Astronomical Society 108 (1948): 372–382.

The Nature of the Universe. Oxford: Basil Blackwell, 1950. First popular science book, a best-seller.

Frontiers of Astronomy. New York: Harper, 1955. First textbook, a model of clarity, and a source of inspiration to students.

With Martin Schwarzschild. “The Evolution of Type II Stars.” Astrophysical Journal Supplement 2 (1955): 1–40. A major contribution to the theory of stellar evolution.

The Black Cloud. New York: Harper, 1957. His first, and arguably his best, science-fiction novel.

With Margaret Burbidge, Geoffrey Burbidge, and William Fowler. “Synthesis of the Elements in Stars.” Reviews of Modern Physics 29 (1957): 547–650. Definitive account of the creation of all of the chemical elements by nuclear processes in stars.

Home Is Where the Wind Blows. Mill Valley, CA: University Science Books, 1994. This autobiography is an objective and accurate source.

With Geoffrey Burbidge and Jayant Narlikar. A Different Approach to Cosmology: From a Static Universe through the Big Bang towards Reality. Cambridge, U.K.: Cambridge University Press, 2000. A research monograph that fully sets out Hoyle’s objections to conventional cosmology and his alternative model.

OTHER SOURCES

Burbidge, Geoffrey. “Sir Fred Hoyle.” Biographical Memoirs of Fellows of the Royal Society London 49 (2003): 213–247. Definitive official biographical summary of Hoyle’s major scientific achievements.

Gough, D., ed. The Scientific Legacy of Fred Hoyle. Cambridge, U.K.: Cambridge University Press, 2005. Collective work in which associates of Hoyle evaluate his scientific legacy in context.

Gregory, J. Fred Hoyle’s Universe. Oxford: Oxford University Press, 2005. Biography.

Mitton, Simon. Conflict in the Cosmos: Fred Hoyle’s Life in Science. Washington, DC: Joseph Henry Press, 2005. Scientific biography.

Wickramasinghe, Chandra. A Journey with Fred Hoyle. Singapore: World Scientific, 2005. Autobiographical reminiscences of a major collaborator, with the emphasis on the search for cosmic life.

Wickramasinghe, Chandra, Geoffrey Burbidge, and Jayant Narlikar, eds. Fred Hoyle’s Universe. Dordrecht, Netherlands: Kluwer Academic Publishers, 2003. Collective work with contributions on all aspects of Hoyle’s research.

Simon Mitton

Hoyle, Fred (1915-1999)

English astronomer

A prolific and talented author in both science fact and fiction, Fred Hoyle is best known for publicizing the controversial steady state theory of the creation of the universe. Hoyle also helped develop radar and advance the understanding of the nuclear processes that power the stars. He has taught at both Cambridge and Cornell universities, received numerous awards and honors, and was knighted in 1972.

Born in Bingley, Yorkshire, England, Hoyle was the son of Benjamin Hoyle and Mabel (Picard) Hoyle. He attended Bingley Grammar School and went on to Emmanuel College at Cambridge, where he studied mathematics and astronomy , receiving his master of arts degree in 1939. On December 28, 1939, Hoyle married Barbara Clark and the couple eventually had two children.

During World War II, Hoyle served in the Admiralty at London, where he helped the British Navy develop radar (radio detection and ranging) technology. The Royal Air Force's victory in the Battle of Britain has been credited to the navy's improvement of radar during this period. After the war, numerous radar dishes were acquired by fledgling radio astronomers and converted into radio telescopes. These amateurs' discoveries in the 1960s ultimately helped to refute the theories Hoyle developed in the 1940s and 1950s.

During the early 1940s, Hoyle focused his attention on an issue that arose through the work of physicist Hans Bethe: energy production in stars. In 1938, Bethe had suggested a sequence of nuclear reactions that fuel the stars: Four hydrogen atoms were fused into a single atom of helium, resulting in a minute amount of mass being converted into energy. While this process of nuclear fusion was consistent with the predicted amounts of stellar energy observed, Bethe's theory did not account for the production of elements heavier than helium—heavy elements that exist within other stars and that are also abundant on Earth.

Hoyle expanded Bethe's findings. Elaborating on gravitational, electrical and nuclear fields, he determined what would happen to elements at ever increasing temperatures. He theorized that when a star has nearly exhausted its supply of hydrogen, nuclear fusion halts, and the outward radiation pressure generated by the fusion reaction also comes to a halt. Without this outward flow, the star begins to collapse because of gravitation. This causes the core of the star to heat up and reach a temperature great enough to fuse helium into carbon . The collapse of the star is then halted by the outward pressure of this new fusion radiation, and the star becomes stable. Hoyle's investigation into the nature of the carbon atom had the added benefit of helping scientists understand the origin of the atoms within the human body.

As the fusion cycle of stellar evolution continues, oxygen , magnesium, sulfur and heavier elements build up until the element iron is formed. At this point, no more fusion reactions can occur, and the star collapses catastrophically, becoming a white dwarf (a star dimmer than the Sun but much more dense). During this implosion, the star's outer layers ignite to become a supernova (an explosion whose luminosity is many times greater than the Sun). The supernova explosion creates elements heavier than iron, which are then hurtled into space by the explosion's force. It was from stellar debris such as this, Hoyle hypothesized, that the second generation stars with the heavier elements were formed.

Hoyle further proposed that the Sun was once part of a binary (double) star system whose companion became a supernova eons ago. The resulting heavy elements it ejected into space became the material from which the planets were formed. Hoyle's remarkable theory of stellar evolution appeared to be correct; it agreed with scientists' observations and accounts for the heavy elements in the solar system . However, whether the Sun had a companion star or not is still disputed; some believe a passing star was the culprit.

Following the war, Hoyle returned to Cambridge and became a professor of astronomy and mathematics. The pivotal point in his career came in 1948 when nuclear physicist George Gamow, building upon a theory first suggested by Georges Lemaître, a Jesuit priest and astonomer, and supported by the telescopic observations of the astronomer Edwin Powell Hubble, published what became known as the big bang theory of the creation of the universe. The big bang theory states that billions of years ago there was an enormous explosion in which all the matter of the universe was created. Galaxies formed and evolved from this matter and are still moving away from each other at tremendous velocities as a result of the explosion.

The concept that the universe had a specific beginning—and the implication that it will have an end—was abhorred by many scientists and laymen. Consequently, Thomas Gold and Hermann Bondi, an astronomer and mathematician respectively, proposed the steady state theory that theorized that the universe was perpetual, an idea that appeared to agree with scientific observation. Through the steady state theory, Gold and Bondi conceived of a universe in which matter was created continuously. As galaxies drift apart, new matter appears in the void and evolves into new galaxies. Since the universe seemed homogeneous (the same) regardless from which direction it was observed, or how far away (i.e. how far back in time) it was observed, Gold and Bondi suggested the cosmos was the same every "where" and every "when." That is, the physical state of the universe remains the same in the past, the present, and the future. The steady state concept had several virtues, not the least of which was avoiding the troublesome issue of the beginning and end of creation. It was simple, symmetrical, and attracted as many adherents as did Gamow's big bang theory. Hoyle became one of steady state's most influential and talented supporters.

Gold and Bondi had not based their concept on general field theory, but instead on an intuitive physical principle. To rectify this, Hoyle delved into the complex equations of Albert Einstein , modified them, and produced a mathematical model that supported the steady state theory, thereby giving it both respectability and plausibility. He became the official spokesperson for the theory and produced many books, some extremely technical, others geared for popular consumption, that publicized steady state cosmology .

The greatest objection to the steady state theory concerned the issue of the continual creation of new matter forming from nothing—an idea that seemed to violate the laws of nature. Hoyle claimed it was easier to accept the idea of matter being created slowly and continuously over the eons than believing that all matter in the universe was created in a single instant from a single blast. For the next fifteen years, proponents of each side interpreted new astronomical discoveries in ways that supported the theory to which each adhered.

In 1952, however, astronomer Walter Baade demonstrated that the accepted cosmological "yardstick" of measurement was seriously flawed. This "yardstick" was derived from the relationship between the brightness and the rate of pulsation of certain stars called Cepheid variable stars. According to Baade's findings, such stars were much farther away than had been previously calculated. This meant that the universe was much older, had been evolving longer, and was more than two times larger than had been believed. If the steady state theory were to hold up, astronomers surveying space would expect to see "old" galaxies created billions of years ago and containing aging stars, as well as "new," recently-created galaxies containing lighter elements and new stars. Yet observed galaxies appeared to be similar in age, supporting the big bang theory. Proving that matter is continuously created was more complicated than it seemed for the steady state theorists. Since space is so vast and the amount of matter that needs to be created at a given moment for the theory to be proven was so small, scientists were not able to detect the instantaneous creation of matter.

The debate between the factions continued. Hoyle acknowledged in his 1962 book Astronomy that there are "cosmological theories in which the universe had a finite and 'explosive' origin," but he manages to discuss them without once using the contentious phrase "big bang"; an ironic point since the term "big bang" is attributed to Hoyle. A decade earlier, Gamow's book The Creation of the Universe remarked that "Astronomical observations" concerning the brightness of the Milky Way stars in relation to the brightness of neighboring stars suggest "that the theory of [Bondi, Gold, and Hoyle] may not correspond to reality." In order to maintain the relevance of his work, Hoyle made several modifications to the steady state theory throughout the 1950s and 1960s.

The 1963 discovery of quasars by Maartin Schmidt created an awkward complication for the steady state theory. Quasars, distant objects brighter than and emitting more energy than stars, did not fit into the steady state explanation of the universe. This tipped the balance toward the big bang theory, which had no trouble embracing these "quasi-stellar" objects. In the following year, Arno Penzias and Robert W. Wilson discovered background microwave radiation in outer space by using radio telescopes. Claiming they had discovered the "remnants" of the big bang explosion with their telescopes, which had evolved from Hoyle's work on radar during World War II, Penzias and Wilson sealed the fate of the steady state theory, which was now abandoned in favor of the big bang theory. Subsequently, Hoyle found working with radio astronomers at Cambridge University increasingly difficult. When his proposed grant for a computer was rejected by the Science Research Council in 1972, Hoyle left the university in favor of working elsewhere.

Hoyle stirred up controversy again in 1981, when he proposed that one-celled life could be found in interstellar dust or comets and life on Earth may have originated from a close encounter with a comet. He also suggested that the abrupt appearance of global epidemics could be caused by space-borne contaminants, a suggestion not taken seriously by most scientists. In 1985, Hoyle ignited yet another controversy when he claimed that the British Museum's fossil of Archaeopteryx was a fake, but he had not been alone in that contention.

A prodigious amount of information has flowed from Hoyle's pen during his career. With his talent for simplifying complex theories for general audiences, he has produced technical treatises, textbooks, popular science fiction stories, an opera libretto, even a radio and a television play. The radio play, Rockets in Ursa Major, and the television play, A for Andromeda, were both written in collaboration with his son, Geoffrey, in 1962. His research on the development of stars and their age, including giants and white dwarfs, helped establish some of cosmology's major theories.

During his career, Hoyle was widely recognized for his achievements with many honors. In 1956, he became a member of the staff at Mount Wilson and Palomar observatories. In 1957, he was elected to the Royal Society of London; the following year he became Plumian Professor of Astronomy and Experimental Philosophy at Cambridge, and in 1962, he became the director of the Institute of Theoretical Astronomy. Following his departure from Cambridge in 1972, he became professor-at-large at Cornell University. Hoyle died at the age of 86.

See also Stellar life cycle

Fred Hoyle

British astronomer and cosmologist Sir Fred Hoyle (born 1915) is best known as the champion of the steady-state theory of the nature of the universe. He also has made significant contributions to the study of stellar evolution and has published more than 40 books, including science fiction.

Fred Hoyle was born in Bingley, Yorkshire, England, on June 24, 1915. His fascination with mathematics and astronomy was evident at an early age. He taught himself the multiplication tables before he was six and would often stay up all night looking through a telescope he received as a gift.

Hoyle was educated at Emmanuel College and St. John's College, Cambridge. He spent six years during World War II with the British Admiralty working on radar development. In 1945, he returned to Cambridge as a lecturer in mathematics. Three years later, in collaboration with the astronomer Thomas Gold and the mathematician Hermann Bondi, he announced refinements to the steady-state theory first put forward by Sir James Jeans in about 1920. Within the framework of Albert Einstein's theory of relativity, Hoyle formulated a mathematical basis for the steady state theory, making the expansion of the universe and the creation of matter interdependent.

Bondi, Gold, and Hoyle found the idea of a sudden beginning to the universe-the so-called big bang theory-philosophically unsatisfactory. They devised a model derived from an extension of the "cosmological principle" that had been used for previous theories. It stated that the universe appeared the same from any location, but not necessarily for all times. They proposed that the decrease in the density of the universe caused by its expansion is exactly balanced by the continuous creation of matter condensing into galaxies that take the place of the galaxies that have receded from the Milky Way, thereby maintaining forever the present appearance of the universe.

Controversy Over Steady-State Theory

In the late 1950s and early 1960s, controversy over the steady state theory grew. New observations of distant galaxies and other phenomena, supporting the big bang theory, weakened the steady state theory, and it has since fallen out of favor with most cosmologists. Although Hoyle was forced to alter some of his conclusions, he attempted to make his theory consistent with new evidence.

Hoyle was elected to the Royal Society in 1957, a year after joining the staff of the Hale Observatories (now the Mount Wilson and Palomar observatories). In collaboration with William Fowler and others in the United States, he formulated theories about the origins of stars as well as about the origins of elements within stars. He directed the Institute of Theoretical Astronomy at Cambridge (1967-73), an institution he was instrumental in founding. Hoyle received a knighthood in 1972.

In 1976, Hoyle and Chandra Wickramasinghe, a fellow professor at the University of Cardiff with whom Hoyle often collaborated, speculated that microorganisms or biochemical compounds from outer space are responsible for originating life on Earth and possibly other parts of the universe.

In 1981, the two coauthored Diseases from Space in which they hypothesized that viruses and bacteria fall into the atmosphere after being incubated in the interiors of comet heads, and that people become ill by breathing this infected air. They supported their theory by stating that the spread of disease is frequently far too rapid to be attributable solely to person-to-person contact. Their theory, known as panspermia, was widely derided.

AIDS From Outer Space?

In December 1988, Hoyle wrote to the Daily Telegraph of London explaining his theory that AIDS originated in outer space. It was immediately dismissed by most British AIDS experts. Many viewed the theory as proof that Hoyle had overstepped the limits of acceptable scientific eccentricity. His letter claimed that viruses from outer space are also responsible for many other epidemics in Britain, including Legionnaires' disease and meningitis. "A small comet disintegrating low in the atmosphere could lead to pathogens being brought down in rainstorms that are geographically localized, " Hoyle claimed. "The comets responsible for new diseases such as AIDS are admittedly rare objects, but the sudden injection into the human population of at least three disjoint viruses point decisively to an input that is external to the Earth, " Hoyle wrote. "We think it most likely in each instance primary entry was secured through infected rainwater entering lesions in feet in the mainly barefoot populations of the Third World with subsequent transmissions proceeding through human contact. Hoyle urged that a major international effort was needed to carry out "a rigorous and continuous microbiological surveillance of rainwater and of groundwater on a worldwide scale. The survival of our species may well be contingent upon this." His ideas were largely viewed as fantasy by other scientists.

In 1996, however, the National Aeronautics and Space Administration (NASA) announced that a small asteroid it had been studying possibly contained fossil remains of primitive life. This finding rekindled speculation about the extraterrestrial "seeding" of life on Earth. Other recent discoveries in astronomy, biology, and chemistry have tended to support the idea first proposed by Hoyle and Wickramasinghe some 20 years earlier. Other scientists, however, remain skeptical. Under closer scrutiny, the evidence turned out to be ragweed pollen and furnace ash. If NASA's microfossils really are the remnants of past life on Mars, then the implications for life and how it got started are profound. The first thing that would have to be explained is why ancient microorganisms on Earth and on Mars are apparently so similar. Some scientists, such as Ian Crawford of University College London, believe that the resemblance may be only superficial.

An Iconoclast

Hoyle has published numerous books challenging many of the basic tenets of modern cosmology. In his 1951 book, The Nature of the Universe, Hoyle rejects the longstanding big bang theory of the origin of the universe in favor of the steady state theory. He expounds further upon the steady state and other theories in The Intelligent Universe: A New View of Creation and Evolution, published in 1977. In it, he dismisses one piece of orthodox science after another, replacing each with ingenious alternatives. He also presents an argument against Darwin's theory of evolution, claiming that "living organisms are too complex to have been produced by chance." Hoyle suggests, instead, that "we owe our existence to another intelligence which created a structure for life as part of a deliberate plan." In describing the attributes of an intelligence superior to ourselves, Hoyle admits that we may have to use the word forbidden in science, "God." He said he found his atheism greatly shaken after calculating the chance that carbon, "uniquely designed to make life possible, " would have precisely the required resonance to permit it to form in sufficient abundance in the universe. "A common sense interpretation of the facts suggests that a super intellect has monkeyed with physics, as well as with chemistry and biology, and that there are no blind forces worth speaking about in nature. The numbers one calculates from the facts seem to me so overwhelming as to put this conclusion almost beyond question." His scientific works for a lay audience include Highlights in Astronomy (1975). He has also written science-fiction, including The Black Cloud (1957), and an autobiography, The Small World of Fred Hoyle (1986).

Hoyle and Wickramasinghe were among the first to argue against the theory that life on Earth originated in a so-called "prebiotic soup." The theory is based on a famous experiment by Stanley Miller in 1953. Deciding to test an earlier hypothesis by Alexander Oparin and John Haldane, Miller started with a sealed mixture of gases thought to be constituents of the primitive Earth's atmosphere. The gases-water vapor, hydrogen, ammonia, and methane-were subjected to an electric discharge, simulating lightning, and the products were found to contain certain amino acids that are building blocks of proteins. This experiment led to the theory that living organisms originated from a prebiotic soup formed in the above manner. This theory soon became the textbook model to describe the origins of life. Hoyle and Wickramasinghe pointed out that the primitive Earth could not have had the hydrogen-rich atmosphere postulated for a prebiotic soup.

Science Fiction

Hoyle has remained controversial. In 1981, he and others made the erroneous claim that a famous Archaeopteryx fossil in the British Museum was a fake. In 1990, he coauthored a theory linking influenza pandemics and sunspot outbreaks. While noting that Hoyle's theses are sometimes far-fetched, reviewers often express their admiration for the author's writing style, statistical data, and its richness in classical quotations. Hoyle has also authored over a dozen science fiction novels, more than half of which have been co-written with his son, Geoffrey Hoyle. Several critics suggest that Hoyle's highly technical and scientific background enhances the credibility and appeal of his novels.

Among the numerous awards and distinctions bestowed on him are the UN Kalinga Prize, the Royal Medal of the Royal Society, and the Gold Medal of the Royal Astronomical Society. In 1997, he was awarded the highly prestigious Crafoord Prize by the Swedish Academy in recognition of outstanding basic research in fields not covered by the Nobel Prize. Hoyle is a Fellow of the Royal Society and a Foreign Associate of the US National Academy of Sciences. He has published over 40 books, including technical science, popular science, and science fiction. Hoyle is an Honorary Fellow of both Emmanuel College and St. John's College Cambridge and an Honorary Professor of Cardiff University in Wales.

Further Reading

Contemporary Authors, Volume 55, Gale, 1991, p. 234-237.

Alberta Report, September 23, 1977, p. 35.

Chicago Tribune, September 4, 1985; December 18, 1986.

Independant, September 18, 1997, p. 3.

Reuters, August 7, 1996.

Scientific American, August, 1996.

The World and I, September 1, 1997, p. 218.

"Sir Fred Hoyle Homepage, " Cardiff University, http://www.cf.ac.uk/uwcc/maths/wickramasinghe/hoyle.html (April 1998).