Akademik

The son of a textile merchant from Bingley in Yorkshire, England, Hoyle was educated at Cambridge. After graduating in 1936 he remained at Cambridge as a graduate student before being elected to a fellowship at St. John's College in 1939. Hoyle spent World War II working on the development of radar at the Admiralty. After the war he returned to Cambridge and was appointed Plumian Professor of Astronomy in 1958.

Hoyle first came to prominence in 1948 with his formulation of the ‘steady-state theory’ of the universe. He was aware that cosmology at the time was inadequate in that it required a smaller age for the universe than geologists had attributed to the Earth. Hoyle's ideas about the steady-state theory were provoked one night in 1946, when he went to see a ghost film with Hermann Bondi (1919––sp;–sp;) and Thomas Gold. The film was in four parts but linked the sections together to create a circular plot in which the end of the film became its beginning. Hoyle later noted that it showed him that unchanging situations need not be static. The universe could perhaps be both unchanging and dynamic.

Hoyle worked out some of the detailed implications of this view in his 1948 paper A New Model for the Expanding Universe. Matter, he argued, was created continually. It arose from a field generated by the matter that already exists – that is, in the manner of the film, “Matter chases its own tail.” Created matter is spread throughout the whole of space and, according to the theory, is being produced at a rate of about one atom per year in a volume equal to that of a large building. It is this creation that drives the expansion of the universe. Matter is distributed evenly through space and therefore new clusters of galaxies are forming as other galaxies are receding into the distance.

Although Hoyle's work was initially treated sympathetically, the steady-state theory failed to cope with new evidence emerging in the 1960s from radio astronomy. Counts of radio sources by Martin Ryle in the 1960s and, in particular, the discovery by Robert Wilson and Arno Penzias of the cosmic background radiation in 1964, convinced most scientists that the universe had begun with a big bang. Hoyle defended his theory strongly, objecting to the accuracy of the radio counts by arguing that they were so constructed as to allow every error to count against the theory. “Properly analyzed,” Hoyle wrote in 1980, “the disproof of the theory claimed in the 1950s and early 1960s fails completely.” He has also suggested that there could be alternative explanations for the background radiation.

Hoyle subsequently felt that he was not committed to the details of any cosmological orthodoxy, such as either the big bang or the steady-state theory of 1948. He spent much time exploring the implications of both theories and, in collaboration with Jayant Narlikar, developing a new theory of gravity. In 1964 they proposed, following some early arguments of Ernst Mach, that the inertia of any piece of matter derives from the rest of the matter in the universe. They also predicted that the gravitational constant changes over time.

Hoyle also worked in the 1950s on the formation of the elements. It was widely believed that carbon could be formed, along with many other elements, in the interior of stars. One reaction proposed required three helium nuclei to fuse into a carbon atom as in:

⁴He + ⁴He + ⁴He -> ¹²C

Hoyle realized that the reaction would take place too infrequently to account for the abundance of carbon in the universe. Another possibility was a two-stage reaction:

⁴He + ⁴He -> ⁸Be

⁸Be + ⁴He -> ¹²C

In this, two helium nuclei first form a beryllium nucleus which fuses in turn with another helium nucleus to form carbon. As the Be has a longer life-time than the collision time of two ⁴He nuclei, the reaction should make the production of carbon more likely. Something more was needed and in 1954 Hoyle predicted that there must be a resonance channel easing the two reaction steps. Hoyle's prediction was confirmed when it was shown experimentally that there was an energy level of 7.65 million electronvolts (MeV) in the ¹²C nucleus, just above the energy of the Be + ⁴He structure of 7.366 MeV.

Further work on the formation of the elements was carried out by Hoyle in collaboration with William Fowler and Geoffrey and Margaret Burbidge. In 1957 their work resulted in a paper, commonly referred to as B²FH, that is one of the most authoritative and comprehensive works of modern science. It describes precisely how all the naturally occurring elements other than hydrogen and helium are formed in the interior of stars.

Hoyle spent much of the early 1960s working in the U.S. at the Hale Observatories and at Princeton. In 1967 he was appointed director of the newly formed Institute of Theoretical Astronomy at Cambridge. It was not a happy time. There were bitter disputes with Martin Ryle and the radio astronomers, demands for apologies, and threats of legal action. Hoyle had problems with his requests for funds from the research councils. In 1973 he resigned and since then has held no permanent post.

He has, however, continued to publish on a wide variety of topics. Much of this later work, often in collaboration with Chandra Wickramsingh of Cardiff University, stems from his claim that the blind operation of physicochemical laws would have been insufficient to shuffle an assortment of amino acids into an enzyme. The odds against this happening by chance were 1 in 10^40,000, as were the chances that an atom with the properties of carbon could be produced by nature. Such considerations led Hoyle to attack the notion of evolution by natural selection.

Hoyle began his campaign with a frontal attack; he asserted that the fossil of Archaeopteryx was a fake. Probably the most famous of all fossils, Archaeopteryx had been bought by the British Museum in 1862 for £700 and supposedly links reptiles with birds. Hoyle published a paper in 1985 claiming that the skeleton was genuine and of a reptile, but that the feathers had been glued on. Hoyle went on to publish a book on the issue, Archaeopteryx, the Story of a Fake (1987) in which he identified Richard Owen as the culprit. Tests of the fossil by the British Museum have failed to detect any glue or cement.

But if enzymes, let alone organisms could not have evolved on Earth, where did they originate? In Lifecloud (1978), Diseases from Space (1979), and Space Travellers (1981), Hoyle argued that life must have come from space. Hoyle was partly led to this view by a longstanding interest in interstellar grains. They had long been thought to be made of ice, but, as they failed to reveal the appropriate infrared absorption bands, this view had to be ruled out. Hoyle pursued the matter and struggled for twenty years to find a particle with the observed spectral properties of the interstellar grains. In 1980 he decided to compare the grains with bacteria and found, to his great surprise, agreement so close that he was forced to conclude that “hitherto unidentified components of dust clouds were in fact bacterial cells.”

Hoyle's new theory allowed him to explain not only the origin of life on Earth but also much about the spread of disease. The abrupt appearance of a new disease, such as syphilis in the 15th century, can be seen as a bacterial seeding from a passing comet. Other epidemiological problems can also be solved in this way. How, for example, Hoyle asks, did a group of Amerindians in Suriname, isolated from all alien contact until recently, become infected with the polio virus? Because, Hoyle believes, both forest and city dwellers were infected with pathogens rained on them from above.

Hoyle's numerous other publications cover such areas as the history of astronomy in his Copernicus (1973), an important textbook, Astronomy and Cosmology (1975), archeo-astronomy in From Stonehenge to Modern Cosmology (1972), and a first volume of autobiography in his The Small World of Fred Hoyle(1986). He has also written fourteen science-fiction novels, the first being The Black Cloud (1957). In 1994 Hoyle published his long-awaited autobiography, Home is Where the Wind Blows: Chapters from a Cosmologist's Life.