Modern Cosmologies PDF

Modern Cosmologies Craig Sean McConnell The interactions between science and religion in the twentieth century regarding the origin of the universe have been quite varied. Throughout the century, some physical cosmologists encouraged discussion of the theological significance of their work. At the...

Modern Cosmologies Craig Sean McConnell The interactions between science and religion in the twentieth century regarding the origin of the universe have been quite varied. Throughout the century, some physical cosmologists encouraged discussion of the theological significance of their work. At the midcentury, the steady state theory was advanced, at least in part, in the hopes of challenging theistic interpretations of ‘big bang’ theories; the steady state theory was soon embraced by some Christians who reframed it in theistic terms. In general, discussions of cosmic origins and evolution have been less rancorous than discussions of the origin of life and organic evolution, for at least three reasons. First, the astronomical evidence regarding the origin of the universe is sparser than the fossil record; many people regarded physical cosmology as mere speculation. Second, cosmological theories of the twentieth century have become increasingly mathematical and inaccessible to non-specialists. Third, many people found the question of the origin and evolution of the universe to be less personal and more esoteric than the question of the origin and evolution of life. Craig Sean McConnell obtained his Ph.D. in the history of science from the University of Wisconsin and is an Associate Professor of Liberal Studies at California State University, Fullerton. He is currently working on a history of the Big Bang – steady state debate. The scientific study of the structure and origin of the universe changed enormously in the twentieth century. At the turn of the century, the most contentious issue was the nature of the nebulae—whether they were part of our galaxy or independent ‘island universes’ outside our galaxy. By the 1980s, Big Bang cosmology had become a subdiscipline of astrophysics with hundreds of practitioners and a constant place in the public eye. The interaction between cosmology and religion has also varied enormously in this period, ranging from disregard to harmonious coexistence to antagonistic opposition. The dynamic of this relationship has often been more dependent on the personalities of key figures in cosmology than on the intrinsic scientific content of the theories themselves. In the nineteenth century, a careful distinction was made between the words ‘cosmogony’ and ‘cosmology,’ the former referring only to theories of the origins of the universe or solar system, the latter to theories of the structure and evolution of the universe after its creation. In the twentieth century, these terms became conflated. In the first half of the century, ‘cosmogony’ was used to refer to structure and evolution in addition to origins. By mid-century, the term ‘cosmology’ was preferred and, by the 1970s, ‘cosmogony’ was an archaic word, unfamiliar to most. This essay traces the major developments in cosmology, understood to be the study of both the origin and the structure of the universe, and religious reaction to these theories. Adopting modern convention, these theories are referred to as ‘cosmologies.’ Observational and Theoretical Cosmology For the first few decades of the twentieth century, two distinct lines of inquiry could properly be considered cosmology, but there was little religious reaction to either. The nature of the nebulae was a major issue in observational astronomy and was debated in a public forum by Heber Curtis (1872–1942) and Harlow Shapley (1885 – 1972) in 1920. Shapley argued that the nebulae were clouds of dust within our galaxy and that our galaxy was the extent of the observable universe. Curtis, echoing the work of John Herschel (1792 – 1871) and Jacobus Kapteyn (1851 – 1922), argued that the nebulae were separate galaxies. The issue was settled when Edwin Hubble (1889 – 1953) and others observed separate stars in the Andromeda Nebula. This confirmation of the extra-galactic nature of the nebulae greatly expanded astronomers’ estimate of the size of the universe but revealed nothing about the origin of the universe and attracted little, if any, religious discussion. The other line of cosmological inquiry was opened in 1917 when Albert Einstein (1879– 1955) turned his general theory of relativity to the scope of the whole universe. Considering the interaction between gravitation and space-time on the largest imaginable scale, Einstein wrote equations that governed the whole cosmos. These equations implied a space-time that was curved so that it was ‘closed,’ like the surface of a sphere, though it was ‘unbounded,’ in that a line without end could be drawn on the surface. The equations were also unstable, implying that the universe was either expanding or contracting. Einstein thought that the universe was stable, so he added a term to the equations that would make them stable as well. This work opened the field of modern theoretical cosmology, though few entered it right away. The mathematics that was required to consider cosmo-logical problems in relativistic terms was notoriously difficult and esoteric, so only those concerned with these problems were able to follow the arguments they contained. Einstein’s equations were soon challenged by Willem de Sitter (1872–1934), who demonstrated in 1917 that other cosmologies were possible, and by Aleksandr Friedman (1888–1925), who wrote equations in 1922 for an expanding universe, but these models were considered by most physicists to be ‘mathematical exercises’ of no physical import. By the 1920s, a few religious writers were challenging the tenets of relativity, particularly the writings of moral relativists, but few had the mathematical skills to investigate these early theoretical cosmologies. Most of the debate about science and religion in the period before 1930 took place between creationists and evolutionists. The Expanding Universe Relativistic cosmology and observational astronomy were brought together in the work of Edwin Hubble and Georges Lemaître (1894 – 1966). Hubble’s study of nebulae led him to the observation that the nebulae are all rushing away from the earth and from each other at a tremendous rate. Though there was initial confusion about how to interpret this observation, by 1930 most astronomers agreed that it meant that the universe itself was expanding. This expansion of the universe could be reconciled with Friedman’s work, and Lemaître did just that. Lemaître was dedicated to linking the work of Fried-man and the work of Hubble, bringing observational evidence to bear on theoretical cosmology. Lemaître proposed that the expansion of the universe could be traced back to a very dense state in the distant past, in which the particles of the whole universe existed as a huge atomic nucleus. He called this nucleus the ‘primeval atom’ and claimed that the expansion of the universe was the aftermath of a process analogous to radioactive decay that took place on a cosmic scale. Lemaître’s original publication appeared in an obscure Belgian journal, but Arthur Eddington (1882 – 1944) brought it to a larger audience by having it republished in the Monthly Notices of the Royal Astronomical Society and by featuring it in his popular book The Expanding Universe (1933). Eddington, a Quaker, made overt attempts to reconcile modern cosmology with religion, suggesting that science should include a spiritual as well as an intellectual appreciation of nature. James Jeans (1877 – 1946) did the same in The Mysterious Universe (1930). The Victoria Institute, a British association dedicated to recon- ciling science and religion, published several articles that were quite approv-ing of the work of Eddington and Jeans. In particular, the distinction that was emerging between notions of an evolving universe, which might be consistent with theistic cosmology, and notions of evolving life, which seemed antagonistic to theistic descriptions of life, placated the members of the Victoria Institute. In God and the Universe (1931), Chapman Cohen (1868–1954) took Edding-ton and Jeans to task for their conciliatory posture toward religion. This collection of essays, many of them previously published in The Freethinker, was sponsored by the Secular Society, a British antireligion organization. Cohen, who wanted to dismiss religion entirely, was annoyed at the presence of spiritual language in Eddington’s The Nature of the Physical World (1928) and Jeans’s The Mysterious Universe and was particularly irritated by the friendly reviews these books received from members of the clergy. Perhaps more influential was an attack by L. Susan Stebbing (1885–1943) in Philosophy and the Physicists (1937). Stebbing, who had more impressive academic credentials than Cohen, chided Eddington and Jeans for making unfounded emotional appeals to religion and for being bad philosophers as well. Subsequent popular works by both Eddington and Jeans contained fewer references to spiritual matters. The Big Bang –Steady State Debate Though Lemaître had hoped for an eventual merging of nuclear physics and theoretical cosmology, it was the work of George Gamow (1904 – 68) and his collaborators Ralph Alpher (1921 – 2007) and Robert Herman (1914 – 97) that brought the science of nuclear physics into modern cosmology. Gamow considered the heat that was required for nuclear reactions and the heat that he believed a primeval atom would contain in the first moments of its decay and proposed that the elements were formed in the first moments of this expansion. This work brought new attention to Lemaître’s primeval atom and showed promise at first, but the theory suffered from several deficits. Gamow could not find a pathway of nuclear reactions to build elements of atomic number five. Worse, Hubble was refining his estimates for the age of the universe, and the figure was quite a bit shorter than the estimates for the age of the earth and the age of some stars. A team of astronomers in England developed an entirely different cosmol-ogy in the hopes of setting these difficulties aside. According to their steady state theory, the universe is eternal. The expansion of the universe has been going on forever and is not evidence of any special moment of creation. Thomas Gold (1920 – 2004) and Hermann Bondi (1919 – 2005) developed this theory from what they called the ‘perfect cosmological principle.’ Gold and Bondi argued that the present does not occupy any special time in the universe. In order to explain the apparent constancy of the density of matter, they had to propose that matter is continuously created in space. The creation of a small amount of hydrogen (approximately one atom in a space the size of a school assembly hall every 100,000 years) would be enough to balance the observed expansion of the universe and would be so rare an occurrence that physicists would likely never see it occur. While Gold and Bondi presented this theory in philosophical terms, their collaborator Fred Hoyle (1915 – 2001) developed a relativistic field equation for the steady state theory. The popular and religious reaction to the debate between these competing theories—the ‘big bang,’ as Fred Hoyle derisively referred to the primeval atom theories, and the steady state theory— was enormous. Public lectures and de-bates were staged, many of them broadcast on radio and television. Pope Pius XII (1876 – 1958), in a speech to the Pontifical Academy of Sciences in 1951, endorsed Lemaître’s primeval atom, an action that amused Gamow, irritated Hoyle, and horrified Lemaître. Gamow cited Pius XII in a paper he published in Physical Review (1952), though he tried to distance himself from the connection between cosmology and biblical creation in his popular text The Creation of the Universe (1952). Lemaître, who was an ordained priest as well as a physicist, advocated a ‘separate spheres’ approach to the issues of science and religion. He felt that they operated on different epistemological foundations and had little of merit to offer each other. Hoyle often claimed that the religious resonance between Genesis and the Big Bang made people believe in the Big Bang irrationally. His The Nature of the Universe (1950), ostensibly a defense of the steady state theory, ends with a long diatribe against religion in general and Christianity in particular. Hoyle revisited these antireligious themes often, in his introductory astronomy textbook, Frontiers of Astronomy (1955); his autobiographical musing, Ten Faces of the Uni- verse (1976); and his essay The Origin of the Universe and the Origin of Religion (1993). Ironically, some religious writers preferred Hoyle’s steady state theory on the grounds that the big bang seemed too deistic and that the hand of God was evident in a universe that was constantly balanced by the creation of new matter. The Big Bang Paradigm A series of observational discoveries in the late 1960s eventually settled the Big Bang – steady state debate in favor of the Big Bang, though Bondi, Gold, and Hoyle never fully abandoned the steady state theory. The debate continued, however, in fundamentalist Christian circles long after the issue was considered settled among astronomers and physicists. Indeed, the steady-state theory attracted new adherents in the pages of the Creation Research Society Quarterly. This renewed interest in the theory seems to have been largely motivated by the desire to discredit evolution by proxy. Big Bang cosmology and evolutionary biology were seen to be complementary theories, and a refutation of the evolutionary Big Bang might challenge biological evolutionary thought as well. In an ironic turnaround, Fred Hoyle’s collaborator and colleague Chandra Wickramasinghe (b. 1939) was called as an expert witness for the creationists in the 1981 Arkansas Creation-Evolution Trial, and Hoyle’s work was enlisted in the defense of creationism. Hoyle and Wickramasinghe argued for the necessity of a cosmic creator, based on calculations estimating the probability of life having originated on earth in the available time frame. Though Hoyle remained evasive about the exact nature of this creator, Wickramasinghe associated the creator directly with his Buddhist beliefs. Hoyle and Wickramasinghe also made claims about extraterrestrial origins of life and were largely marginalized in the scientific community. Philosopher of science Michael Ruse (b. 1940), testifying on behalf of the evolutionists, occasionally conflated Big Bang cosmology with evolution, but for the most part, the trial was focused on the biological sciences. Fine Tuning and the Anthropic Principle In the 1960s, several physicists noticed that the numerical values for fundamental physical constants—such as the strength of electromagnetism, the strength of gravity, and the binding force of nucleons within atomic nuclei—existed within very narrow ranges that were consistent with a universe in which life is possible. Were any of these constants slightly larger or slightly smaller, it would no longer be possible for nucleons to form chemical elements or for stars to form. In a symposium honoring the five hundredth anniversary of Nicolaus Copernicus’s birth, Brandon Carter (b. 1942) introduced the ‘anthropic principle,’ in opposition to the so-called Copernican principle. In contrast to the view that we do not occupy a special place in the universe, Carter argued that we occupy a special time in the universe’s evolution. Over the next decades, the anthropic principle drew progressively less attention from physicists. Some critics identified the principle as a mere label for phenomena that were not adequately understood; others viewed it as a tautology—a mere restatement of how things are rather than an explanation of how they came to be so. In other quarters, the anthropic principle was attacked for being unverifiable and for being unfalsifiable. For most physicists, the gravitas of the anthropic principle was further undermined by the inflationary version of Big Bang cosmology developed in the 1980s. In inflationary cosmology, gravitation is considered to have been a repulsive force in the first moments after the Big Bang. Such a bizarre notion was required to explain the density and distribution of matter in the universe; in inflationary cosmology, physical constants are not nearly as fine-tuned as they appeared to be in previous models. Nonetheless, the anthropic principle continues to draw the attention of some theoreticians. In 1988, cosmologists John Barrow (b. 1952) and Frank Tipler (b. 1947) coauthored a volume titled The Anthropic Cosmological Principle, in which they trace the history of fine-tuning and connect the concept to the arguments for Intelligent Design. Advances in Radio Astronomy and SETI Cosmology was aided considerably by advances in radio astronomy. Whether using repurposed communications equipment or specially built receivers, radio astronomers were able to look deeper into the sky than were optical astronomers. Their instruments were not limited by the technical difficulties of producing glass to the tolerances necessary for optical astronomy. An enormous steerable dish 250 feet in diameter was constructed at the Jodrell Bank Observatory in the north of England in the 1950s. A similar facility was built in Australia with a dish 210 feet in diameter. A one-thousand-foot dish at the Arecibo Observatory in Puerto Rico was built into a natural sinkhole in the 1960s. In the 1970s, a collection of twenty-seven dishes, each of them over 80 feet in diameter, was strategically arranged in a Very Large Array (VLA) in New Mexico. One of the fringe research projects pursued by some in the field was the Search for Extraterrestrial Intelligence (SETI). Using radio telescopes to scan frequencies that an alien civilization might use to announce their existence, radio astronomers hoped to confirm the reception of signals that would demonstrate that human civilization is not the only civilization in the universe. A group of scientists submitted a study to the United States National Aeronautics and Space Administration (NASA) proposing the construction of a facility with 1,500 dishes specifically designed for SETI. The project was not funded. Indeed, many scoffed at the project, and several of the astronomers associated with the project faced diminished stature in the field as a result of their involvement in the study. In the 1980s, a small budget was set aside for SETI studies to be conducted with existing equipment. The nonprofit SETI Institute was formed in Mountain View, California, to coordinate these studies. In many instances, SETI research is conducted by scouring through data astronomers have gathered in the course of studying astronomical objects. Similarly, the SETI@home program, initiated in 1999 at the University of California, Berkeley, makes use of idle computing time on personal computers to conduct that analysis. Volunteers download distributed networking software that runs in the background of other processes and scans radio astronomy data for evidence of alien intelligence. Despite the failure of these programs to detect any evidence of extraterrestrial intelligence to this point, many SETI astronomers and SETI enthusiasts have speculated that a positive result would have tremendous implications for man’s sense of his place in the universe. Surveys of believers and theologians do not support these speculations. While nonbelievers assume that the discovery of extraterrestrial intelligence would have a huge impact on theology, most believers assume that the existence of extraterrestrial intelligence would have no effect on their beliefs at all. The Standard Model Concepts and data from the field of particle physics were incorporated into the emerging Big Bang paradigm, strengthening its credibility as a branch of physical science. Cosmologists posited that the early universe was an extremely dense and extremely hot region in which elementary particles precipitated out of energy much as raindrops precipitated out of clouds. This metanarrative of the basic forces of nature and the constituent matter of the universe is known as the ‘standard model.’ As measurements of the ratio of hydrogen to helium in the universe became more precise, they matched predictions made by cosmologists based on the assumption that primordial hydrogen would be fused into helium nuclei in the early moments of the universe. Educational materials developed by NASA in this period emphasized that a Big Bang universe is an evolving universe. This synergy with the principles of evolutionary biology made Big Bang cosmology a target for some conservative Christians trying to eliminate the teaching of evolution in public schools. Thus, for example, in 1999, the Kansas State Department of Education made teaching biological evolution, the age of the earth, and the origin of the universe permissible but not mandatory. All of these subjects had been mandatory before 1999. In the 1970s and 1980s, some cosmologists returned to a more harmonious representation of the relationship between cosmology and religion. British cosmologists such as Paul Davies (b. 1946; emigrated to Australia, 1990), in his God and the New Physics (1983), have returned to speaking of cosmology and religion as addressing the same questions. American cosmologists by contrast have largely ignored the question of the religious implications of cosmology. A notable exception is The Physics of Immortality (1994), in which Frank Tipler claims to have reduced theology to a subdiscipline of physics. He uses cosmo-logical arguments to demonstrate the existence of God and the certainty of an afterlife. The book sold well, though it received numerous skeptical reviews. Consideration of cosmology by religious thinkers has typically been overshadowed by consideration of evolution. For many, cosmology is not as personally offensive as evolutionary biology. Others find cosmology so speculative that it is not worthy of a protracted rebuttal. The esoteric mathematics of general relativity, which has been the language of cosmology since 1917, makes it hard for most people to engage the arguments. Religious scientists concerned with reconciling science and religion have typically studied subjects in geology and evolution, and in fact, many of the discussions of cosmology and theology revert to discussions of evolution and theology.