by Peter Watson
At this point, with the Princeton experiment ready to start, Penzias called Peebles and Dicke, an exchange that became famous in physics. Comparing what Dicke and Peebles knew about the evolution of background noise and the observations of Penzias and Wilson, the two teams decided to publish in tandem a pair of papers in which Penzias and Wilson would describe their observations while Dicke and Peebles gave the cosmological interpretation – that this was indeed the radiation left over from the Big Bang. Within science, this created almost as huge a sensation as the confirmation of the Big Bang itself.21 It was this duo of papers published in the Astrophysical Journal that caused most scientists to finally accept the Big Bang theory – not unlike the acceptance of continental drift after Eltanin’s sweep across the Pacific-Antarctic Ridge.22 In 1978, Penzias and Wilson received the Nobel Prize.
Long before then, there had been a synthesis, bringing together what was known about the behaviour of elementary particles, nuclear reactions, and Einstein’s theories of relativity to produce a detailed theory about the origin and evolution of the universe. The most famous summing up of these complex ideas was Steven Weinberg’s book The First Three Minutes, published in 1977 and on which my account is chiefly based. The first thing that may be said about the ‘singularity,’ as physicists call Time Zero, is that technically all the laws of physics break down. Therefore, we cannot know exactly what happened at the moment of the Big Bang, only nanoseconds later (a nanosecond is a millionth of a second). Steven Weinberg gives the following chronology, which for ease of digestion to the layperson is set out here as a table.
After 0.0001 (10–4) seconds:
This, the original ‘moment of creation,’ occurred 15 billion years ago. The temperature of the universe at this near-original moment was 1012 K, or 1,000 billion degrees (written out, that is 1,000,000,000,000 degrees). The density of the universe at this stage was 1014 – 100,000,000,000,000 – grams per cubic centimetre (the density of water is 1 gram per cubic centimetre). Photons and particles were interchangeable at this point.
After 0.01 (10–2) seconds:
The temperature was 100 billion K.
After 0.1 seconds:
The temperature was 30 billion K.
After 13.8 seconds:
The temperature was 3 billion K, and nuclei of deuterium were beginning to form. These consisted of one proton and one neutron, but they would have soon been knocked apart by collisions with other particles.
After 3 minutes, 2 seconds:
The temperature was 1 billion K (about seventy times as hot as the sun is now). Nuclei of deuterium and helium formed.
After 4 minutes:
The universe consisted of 25 percent helium and the rest ‘lone’ protons, hydrogen nuclei.
After 300,000 years:
The temperature was 6,000 K (roughly the same as the surface of the sun), when photons would be too weak to knock electrons off atoms. At this point the Big Bang could be said to be over. The universe expands ‘relatively quietly,’ cooling all the while.
After 1 million years:
Stars and galaxies begin to form, when nucleosynthesis takes place and the heavy elements are formed, which will give rise to the Sun and Earth.23
At this point the whole process becomes more accessible to experimentation, because particle accelerators allowed physicists to reproduce some of the conditions inside stars. These show that the building blocks of the elements are hydrogen, helium, and alpha particles, which are helium-4 nuclei. These are added to existing nuclei, so that the elements build up in steps of 4 atomic mass units: ‘Two helium-4 nuclei, for example, become beryllium-8, three helium-4 nuclei become carbon-12, which just happens to be stable. This is important: each carbon-12 nucleus contains slightly less mass than three alpha particles which went to make it up. Therefore energy is released, in line with Einstein’s famous equation, E=mc2, releasing energy to produce more reactions and more elements. The building continued, in stars: oxygen-16, neon-20, magnesium-24, and eventually silicon-28.’ ‘The ultimate step,’ as Weinberg describes it, ‘occurs when pairs of siIicon-28 nuclei combine to form iron-56 and related elements such as nickel-56 and cobalt-56. These are the most stable of all.’ Liquid iron, remember, is the core of the earth. This narrative of the early universe was brilliant science but also a great work of the imagination, the second evolutionary synthesis of the century.24 It was more even than that, for although imagination of a high order was required, it also needed to conform to the evidence (such evidence as there was, anyway). As an intellectual exercise it was on a par with the ideas of Copernicus, Galileo, and Darwin.25
But background radiation was not the only form of radio waves from deep space discovered in the 1960s. Astronomers had observed many other kinds of radio activity unconnected with optical stars or galaxies. Then, in 1963, the Moon passed in front of one of those sources, number 273 in the Third Cambridge Catalogue of the Heavens and therefore known as 3C 273. Astronomers carefully tracked the exact moment when the edge of the Moon cut off the radio noise from 3C 273 – pinpointing the source in this way enabled them to identify the objects as ‘star-like,’ but they also found that the source had a very large redshift, meaning it was well outside our Milky Way galaxy. It was subsequently shown that these ‘quasi-stellar’ objects, or quasars, form the heart of distant galaxies that are so far away that such light as reaches us left them when the universe was very young, more than 10 billion years ago. What brightness there is, however, suggests that their energy emanates from an area roughly one light day across, more or less the dimensions of the solar system. Calculations show that quasars must therefore radiate ‘about 1,000 times as much energy as all the stars in the Milky Way put together.’ In 1967 John Wheeler, an American physicist who had studied in Copenhagen and worked on the Manhattan Project, revived the eighteenth-century theory of black holes as the best explanation for quasars. Black holes had been regarded as mathematical curiosities until relativity theory suggested they must actually exist. A black hole is an area where matter is so dense, and gravity so strong, that nothing, not even light, can escape: ‘The energy we hear as radio noise comes from masses of material being swallowed at a fantastic rate.’26
Pulsars were another form of astronomical object detected by radio waves. They were discovered – accidentally, like background radiation – in 1967 by Jocelyn Burnell, a radio astronomer in Cambridge. She was using a radio telescope to study quasars when she stumbled on a completely unknown radio source. The pulses were extremely precise – so precise that at first the Cambridge astronomers thought they might be signals from a distant civilisation. But the discovery of many more showed they must be a natural phenomenon. The pulsing was so rapid that two things suggested themselves: the sources were small, and they were spinning. Only a small object spinning fast could produce such pulses, rather like a very rapid lighthouse beam coming round every so often. The small size of the pulsars told astronomers that they must be either white dwarfs, stars with the mass of the sun? packed into the size of the earth, or neutron stars, with the mass of the sun ‘packed into a sphere less than ten kilometres across.’27 When it was shown that white dwarfs could not rotate fast enough to produce such pulses without falling apart, scientists finally had to accept that neutron stars exist.28 These superdense stars, midway between white dwarfs and black holes, have a solid crust of iron above a fluid inner core made of neutrons and, possibly, quarks. The density of neutron stars has been calculated by physicist John Gribbin as 1 million billion times greater than water, meaning that each cubic centimetre of such a star would weigh 100 million tons.29 The significance of pulsars being identified as neutron stars was that it more or less completed the sequence of stellar evolution. Stars form as cooling gas; as they contract they get hotter, so hot eventually that nuclear reactions take place; this is known as the ‘main sequence’ of stars. After that, depending on their size and when a crucial temperature is reached, quantum processes trigger a slight expansion that is als
o fairly stable – and the star is now a red giant. Toward the end of its life, a star sheds its outer layers, leaving a dense core in which all nuclear reactions have stopped – it is now a white dwarf and will cool for millions of years, eventually becoming a black dwarf, unless it is very large, in which case it ends as a dramatic supernova explosion, when it shines very brightly, very briefly, scattering heavy elements into space, out of which other heavenly bodies form and without which life could not exist.30 It is these supernovae explosions that give rise to neutron stars and, in some cases, black holes. And so, the marriage of physics and astronomy – quasars and quarks, pulsars and particles, relativity, the formation of the elements, the lives of stars – was all synthesised into one consistent, coherent, story.31
Once one gets over the breathtaking numbers involved in anything to do with the universe, and accepts the sheer weirdness not only of particles but of heavenly bodies, one cannot escape the fact of how inhospitable much of the universe is – very hot, very cold, very radioactive, unimaginably dense. No life as we can conceive it could ever exist in these vast reaches of space. The heavens were as awesome as they had ever been, ever since man’s observation of the sun and the stars began. But heaven was no longer heaven, if by that was meant the same thing as paradise.
When the crew of Apollo 8 returned from their dangerous mission around the Moon, at the end of 1968, they gave a broadcast in which they treated earthlings to readings from the Bible. ‘And the Earth was without form, and void,’ read Frank Borman, quoting from Genesis.32 ‘And darkness was upon the face of the deep,’ continued Bill Anders. This did not please everyone, and the American television networks were swamped with calls from viewers complaining about the intrusion of religion at such a time. But you didn’t have to be much of a philosopher to see that the revolution in the study of the heavens, and the theories being propounded as a result of so many observations, both before the advent of satellites and since, could not be easily reconciled with many traditional religious ideas. Not only had man evolved; so had the very heavens themselves. The modern sciences of astrophysics and cosmology were not the only aspects of the modern world to bring about changes in religious belief, not by a long way. But they were not irrelevant either.
So far as the major religions of the world were concerned, there were three important developments after the end of World War II. Two of these concerned Christianity, and the third involved the religions of the East, especially India. (So far as Judaism and Islam were concerned, their problems were mainly political, arising from the creation of the state of Israel in 1948.) The upsurge of interest on the part of Westerners in the religions of the East is considered in the next chapter. Here we shall examine the two main areas of thought that taxed Christianity.
These may be simply put: the continuing discoveries of science, in particular archaeological discoveries in the Middle East, what some people called the Holy Land, and existentialism. In 1947, a year before Israel was founded, there occurred the most spectacular excavation of archaeological material since the unearthing of Tutankhamen’s tomb in 1922. This was the discovery of the so-called Dead Sea Scrolls at Qumran, which were first found in a cave by an Arab boy, Muhammad Adh-Dhib, chasing a wayward goat as it scampered up a rock face overlooking the inland sea. There were fewer parallels with the boys who discovered Lascaux than at first seemed because events in the wake of Muhammad’s find involved far darker dealings. The area was highly unstable politically, and local traders and even religious leaders held back on the truth, hiding documents by burying them in soil so unsuitable that many were destroyed. It took months for the full picture to emerge, so that by the time trained archaeologists were able to visit the cave where Muhammad had first stumbled across the jars containing the scrolls, much of the context had been destroyed.33
Even so, the significance of the scrolls could not be minimised. Until that point, the last word on biblical archaeology had been F. G. Kenyon’s The Bible and Archaeology, published in 1940. Broadly speaking, this argued that the thrust of science had been to confirm the biblical account, in particular that Jericho, as the Bible said had existed from around 2000 BC to 1400 BC and then been destroyed. The significance of the scrolls was more profound. They had belonged to an early sect that had existed in Palestine from perhaps 135 BC to shortly before the destruction of Jerusalem in ALL 70.34 The scrolls contained early texts from parts of the Bible, including Isaiah. At that stage, scholars were divided on how the Bible had been put together, and many thought there had been a fight in the early centuries as to what should be included and what left out. In other words, in this scenario the Bible too had evolved. But the Qumran texts showed that the Old Testament at least was already, in the first century AD, more or less written as we know it. A second and even more incendiary significance of the Qumran texts was that, as research showed, they had belonged to a very ascetic sect known as the Essenes, who had a Teacher of Righteousness and called themselves either the Sons of Zadok or the Children of Light.35 Jesus wasn’t referred to in the Qumran texts, and there were some marked differences between their lifestyle and his. But the existence of this extremist sect, at the very time Jesus is supposed to have lived, threw a great deal of light on the emergence of Christianity. Many of the events referred to in the Qumran documents are either exactly as described in the Bible, or thinly disguised allegories. The prospect was held out, therefore, that Jesus was a similar figure, beginning his career as the leader of just such a Jewish sect.36
The very authority and plausibility of this overall historical context, as expanded by recent scholarship, was most threatening to Christianity. On 12 August 1950 Pope Pius XII issued Humani Generis, an encyclical designed specifically to counter ‘extreme non-Christian philosophies of evolutionism, existentialism, and historicism as contributing to the spread of error.’37 Not that the encyclical was entirely defensive: the document called on Catholic philosophers and theologians to study these other philosophies ‘for the purpose of combating them,’ conceding that ‘each of these philosophies contains a certain amount of truth.’38 The encyclical condemned all attempts to ‘empty the Genesis accounts in the Old Testament,’ took the view that evolution was not as yet a proven fact, and insisted that polygenism (the idea that man evolved more than once, in several places across the earth) could not be taught (i.e., accepted), ‘for it is not yet apparent how polygenism is to be reconciled with the traditional teaching of the Church on original sin.’39 The encyclical turned existential thinking on its head, blaming Heidegger, Sartre, and the others for the gloom and anxiety that many people felt.
More lively, more original – and certainly more readable – resistance to existentialism, evolutionism, and historicism came not from the Vatican but from independent theologians who, in some cases, were themselves at loggerheads with Rome. Paul Tillich, for example, was a pre-eminent religious existentialist. Born in August 1886 in a small village near Brandenburg, he studied theology in Berlin, Tubingen, and Halle and was ordained in 1912. He was a chaplain in the German army in World War I and afterward, in the mid-1920S, was professor of theology at Marburg, where he came under the influence of Heidegger. In 1929 he moved to Frankfurt, where he became professor of philosophy and came into contact with the Frankfurt School.40 His books, especially Systematic Theology (2 volumes, 1953 and 1957) and The Courage to Be (1952), had an enormous impact. A great believer in the aims of socialism, including many aspects of Marxism, Tillich was instantly dismissed when the Nazis came to power. Fortunately, Reinhald Niebuhr happened to be in Germany that summer and invited him to the Union Theological Seminary in New York.