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The idea that the universe is expanding from some primordial dense core was first proposed in 1922 by the Russian mathematician Alexander Friedmann, working entirely from theory based on Einstein’s general relativity equations. Five years later, and apparently independently, the Belgian astronomer Abbé George Lemaître, also noted that Einstein’s equations predicted that the universe should be expanding. Like Friedmann, Lemaître challenged Einstein’s cosmological constancy, and concluded that if the universe is expanding now, logically it must have been less expanded, or more dense, at earlier times—ultimately beginning from a superdense state which he called the “cosmic egg”. Building on Hubble’s observations and on the ideas of Friedmann and Lemaître, Russian-American astrophysicist George Gamow (1904-1968) popularized the notion that the universe began in an infinitesimal singularity and a mighty explosion which he called the “Big Bang”. And thus, our modern creation story was born. • Background microwave radiation. In 1946, Gamow added more fuel to the Big Bang theory by pointing out that if such an explosion had occurred, it would have created immensely hot radiation, but that this would have lost its energy and cooled as the universe expanded. He predicted that such an “echo” of the Big Bang should exist today, and be detectable, in the form of background microwave radiation of about 5°Kelvin (that is, about five degrees above absolute zero). Since the primordial cosmic “quantum” began from a singularity, its energy-density would have had no particular bias in any direction. Therefore, as it exploded, inflated, and expanded it would have retained its original homogeneity, and the magnitude of the background radiation would be consistent, no matter in which direction researchers looked. Such a prediction was in the tradition of the purest science: Based on the observational evidence of galactic red-shift, physicists deduced that the galaxies were moving away from each other at speeds proportional to their distances. In other words, the universe is expanding. Based on the data derived from the selection of galaxies that were observed, scientists extrapolated to the universe as a whole—induction—that the explosively expanding galaxies must have originated from a point of common convergence in the past: the superdense primordial cosmic “quantum”. For the observed universe to have originated from such a state, mathematical theory (consistent with general relativity) requires that the cosmic “quantum” exploded from its geometrical singularity, creating time, space, and the universe of energy and physical laws. Such an explosion, theory predicts, would result in an echo of the Big Bang detectable today as “fossil” microwave background radiation. In May 1964, two American astrophysicists, Arno Penzias and Robert Wilson detected microwave background radiation at 3°K, just as Gamow had predicted. (The 2°K difference between Gamow’s prediction and that actually observed is insignificant compared to the unimaginable temperature of 1032 degrees K an instant after the cosmic “quantum” exploded.) Further astronomical research confirmed the Penzias-Wilson 3°K and Gamow’s prediction that it would be isotropic, the same in all directions. Taken together, these two pieces of observational data—the Hubble red-shift and the 3°K microwave background radiation—are considered to be the strongest foundation for accepting the theory that the universe began in a Big Bang creation. But supporters of this theory cite many other items of “evidence”—some of which derive from observations, and others which depend on mathematical deductions from other aspects of the theory. For example, two such pieces of “evidence” often cited as confirmatory of the Big Bang theory are the chemical composition of the universe (understood to conform to what theory says would have happened as a result of the primordial fireball explosion), and the existence of so-called dark matter (required by theory to account for the large-scale structures of the universe, such as galaxies, clusters and superclusters). • Ratio of chemical elements. According to the theory, the evolution of chemical elements after the Big Bang would result in a particular ratio of quantities of deuterium, helium, and lithium. Predictions from theory can then be subjected to experimentational observation by nuclear physicists. Although interpretations of the data are disputed, some astrophysicists claim that observation does confirm that the existing ratios of deuterium and helium agree with theory. However, as we shall see, other physicists have serious doubts about the legitimacy of these conclusions. • Dark matter. Given the immense velocities of the primordial particles from the initial exploding cosmic fireball, the expansion of matter-energy would rush on out to the most distant reaches of spacetime, eternally expanding, never coming together to form even the seed gas-and-dust clouds of the smallest galaxies. Unless, that is, the expansion was slowed down sufficiently by gravitation. But as Einstein showed, gravitation is not a “force” that exists independently of matter or mass (in fact, this insight is already implicit in Newton’s laws of force). In other words, for there to be sufficient gravity to counteract the explosive outward thrust of matter from the Big Bang, there would have to be a minimum amount of matter in the universe. However, observation (beefed up with some powerful number-crunching) shows that the total amount of observable matter in the universe falls dramatically short of what would be required to slow expansion. In fact, it is short by a staggering 99 percent! In other words, given the force of the initial expansion, and given the mass of matter in the universe, galaxies, stars, and planets would be impossible. Yet obviously galaxies do exist—we live in one. Ergo, there just has to be more—a lot more—matter lurking, undetected in the universe, dark matter. Such a situation would seriously compromise any theory, unless there was some evidence for the “missing matter”. Fortunately, for the Big Bang theorists, astronomers studying the rotation of galaxies and clusters noticed that the magnitudes of the observed rotational velocities could not be accounted for by the calculated mass of all the stars in a galaxy, or of all the galaxies in a rotating cluster. The only way to account for the observed rotations is to assume that the extra mass required for the rotations resides in undetected, non-luminous, or “dark”, matter. This is indirect evidence, of course, and not nearly as impressive as the red-shift evidence for expansion or the 3°K background microwave radiation evidence for a superhot and homogenous early history to the universe. Nonetheless, given standard Newtonian mechanics, the observed magnitude of galactic rotation stands as evidence for more mass than is contained in the visible stars. However, even this extra dark matter would be insufficient—by a factor of around 99 percent—to account for the mass needed to halt or sufficiently slow expansion and permit the formation of galaxies (Lerner, 1991, p. 35). Nevertheless, given the evidence for at least some dark matter, Big Bang cosmologists are confident that the rest of the missing matter will show up in time. And it has to—for otherwise the Big Bang theory blatantly contradicts the observation that clusters, galaxies, stars, and planets exist. The fact that there are humans around, living on a planet, in a solar system, in a spiral galaxy, who can formulate creation myths such as the Big Bang requires that such dark matter exists—or else the theory is hopelessly wrong. But this is very strange science. It offers us a story of the universe based on what must be (according to the theory), rather than on what observation reveals. Nevertheless, the other evidence for the Big Bang seems so strong, so compatible with other deeply established areas of physics, such as relativity theory and quantum mechanics, that despite difficulties such as the problematic existence and nature of dark matter, most modern cosmologists, and astrophysicists accept the story of the Big Bang. It is our era’s dominant creation myth, taken for granted by most scientists and by many lay people. In essence, the main features of our modern creation story are these: The Modern Creation Myth In the beginning, some 10 to 20 billion years ago, there was no space, no time, no matter, no minds. There was only one thing: the entire universe squeezed into an infinitesimal speck. By some accounts, this “speck” was smaller than the head of a pin, others say it was about the size of a proton, yet others say it was so infinitesimally small that it had no dimensions at all. In any case, this tiny primordial “quantum”, packed unimaginably to bursting point with all the vast energy of the entire universe, quivered with some infinitesimal instability which triggered a mighty explosion. The pent-up cosmic energy burst forth in a Big Bang, creating space and time, and the primal conditions for the formation of matter. We cannot tell what the universe was like at the moment of the Big Bang because at that instant all the known laws of physics break down. We must begin the details of our story a split-instant later at 10-43 second, when the temperature was 1032 degrees Kelvin. Just a micro-tad later, at 10-32 second, the first elementary particles appeared (quarks, electrons, neutrinos, and photons)—along with all their antiparticles. As the particles and antiparticles collided they annihilated each other in massive bursts of radiation. However, because there were slightly more particles than antiparticles, there was a residue of “true” particles. These survived to create all the matter of the universe. At one millionth of a second, when the universe had inflated to about the size of our solar system, quarks began to form protons and neutrons, joining the soup of electrons, neutrinos, and photons. Three minutes later, single protons (hydrogen nuclei) and the pairing of single protons and single neutrons (deuterium nuclei) were joined by nuclei of double-protons and double neutrons (helium nuclei). And so, more or less, things remained for the next 300,000 years, until the universe cooled enough for electrons to attach themselves to the hydrogen and helium nuclei, forming the first atoms. As the universe continued to expand and cool, its rapid expansion was slowed down by the gravitation acting between all the countless trillions of atoms. Gradually, little clumps of atoms congregated, growing more and more under the influence of gravity, until after some two or three billion years, the first galaxies formed—hundreds of billions of them, each a “hot house” for the creation of hundreds of billions of stars. About 5 billion years ago, on a spiral arm of one of these average galaxies, one star happened to become part of a solar system, in which at least one planet had the right conditions for its chemicals to begin to form complex molecules, such as proteins and nuclei acids. Sometime during its first billion years or so, the planet’s complex macromolecules, pushed about by random natural forces, happened to form helical-type structures which enabled the giant molecules to split and replicate. Sometime later, some of these replicating molecules happened to find themselves encapsulated inside a coat of lipid and protein, which formed a membrane. And so life, the first living cell, appeared. And so the story goes . . . But it is not a story that goes unchallenged. There are problems with Big Bang cosmology, serious problems which conflict with observation. And when theory conflicts with observation, authentic scientific methodology requires us to either change the theory to accommodate the observational data, or, if the discrepancies are too great, to drop it altogether. A further possibility, of course, is to doubt the accuracy or veridicality of the observations. However, if the critical observations are themselves required to support other elements of the theory, then, for internal consistency, the theory cannot reject the observational evidence. In such a situation, a theory would be caught on the horns of a dilemma. And this appears to be the case with the Big Bang. Already, signs within the ranks of the scientific community indicate that the Big Bang theory may be past its prime. For example, in 1988 the international peer-review science journal Nature ran an editorial headlined “Down with the Big Bang”, in which it described the theory as “unacceptable”, and predicted that “it is unlikely to survive the decade ahead” (cited in Lerner, 1991, p. 14). In one year's time, if Nature is correct, we may expect to see the Big Bang go out with a whimper. However, that seems unlikely, given the vested interests in academic status and research funds of all those whose careers have up to now, in one way or another, accepted the theory as fact, and not simply as theory which should be given up when sufficient data accumulate which it cannot accommodate. But as Thomas Kuhn (1966) pointed out, the inertia of the status quo in science—its dominant paradigm—frequently keeps inadequate theories in place even in the face of mounting anomalies. One notable example of scientific inertia is the dogged reluctance of a majority of scientists to take seriously the data of parapsychology (or psi research), despite the voluminous documentation of meticulous experimental and statistical methods (Jahn & Dunne 1987). Quite simply, if the data do not fit the paradigm, they tend to be ignored—unless and until the weight of anomalies eventually collapses the old belief systems and their underlying assumptions are revised. The following is a list of problems which Big Bang theory needs to address if it is to maintain a warrant to be the dominant cosmology myth of our age. Challenges to the Big Bang • Problem 1: The Universe is Homogeneous Observation shows that the 3°K background radiation is uniform in all directions. Yet, according to the theory, the background radiation formed when the universe was only 300,000 years old. Since light is the fastest mode of communication, any parts of the universe separated by more than 300,000 light-years would not have had sufficient time to influence each other to equalize their temperatures. Yet there are regions of the universe separated by hundreds of millions of light-years. Given what we know of thermodynamics and the dynamics of complex systems, in addition to the inherent randomness of Brownian motion and quantum uncertainty, we would expect spontaneous differences in thermodynamic gradients to occur between different regions of the universe as it expanded over time. There is no a priori reason to account for universal homogeneity in the background radiation as it cooled from 10,000°K over the 15 billion years or so since the formation of atoms when the universe was only 300,000 years old to the observed 3°K of today. Given the immense distances separating distinct regions of the universe—hundreds of millions of light years—and the natural tendency of systems to randomly fluctuate over time, how can the 3°K radiation be uniform across such distances? Response. This “problem” is posed by Trinh Xuan Thuan in his new book The Secret Melody (1995). I’m not convinced that this is a really serious threat to Big Bang theory. It strikes me that the assumption of spontaneous thermodynamic gradients appearing randomly over time, while perhaps true on quantum or microscopic scales, is unlikely to hold for macroscopic dimensions. I think that entropic annihilation or evening out of thermodynamic gradients over time is far more likely. Thus, if the initial “flare up” of radiation at the 300,000 year mark of cosmic evolution (when free electrons were captured by atomic formations making matter transparent to primordial radiation for the first time), if this radiation began homogeneously, then what reason do we have for not believing it would continue to be so? If, however, at the 300,000-year mark the radiation was inhomogeneous, then the homogeneity of the “fossil” background radiation would be a problem because it would seem to defy the relativistic limit to the speed of light. Counter-response. The issue, then, seems to come down to this: According to Big Bang theory, was the 300,000 year radiation homogeneous or inhomogeneous? Given the enormous explosive reactions between the primordial particles constantly happening throughout the nascent universe form its first moment to its 300,000 year anniversary, it seems too much to expect homogeneity across 300,000 light-years. So perhaps, after all, Thuan’s “problem” remains a difficulty for Big Bang theory? • Problem 2: The Universe Has Large-Scale Structure In some ways this is the flip-side of the previous problem: How come the universe is not homogeneous? The fact is, as the most casual observation reveals, the universe has complex structure. It is not homogeneous: Galaxies form clusters, clusters form superclusters, and since 1986 we know that superclusters themselves form complexes (Brent Tully, 1986). The problem is this: Given the known mass density of the universe, and the force of gravity, 20 billion years is just not enough time for such immensely large objects to form. From observations of red-shifts, as well as from other methods of measurement, “Galaxies almost never move much faster than a thousand kilometers per second, about one-three-hundredth as fast as the speed of light” (Lerner, p. 23). Since the Big Bang, therefore, (at most 20 billion years ago) galaxies could have moved only about 65 million light-years. However, in 1986 Brent Tully, an astronomer from the University of Hawaii, discovered that “almost all the galaxies within a distance of a billion light-years of earth are concentrated into huge ribbons of matter about a billion light-years long, three hundred million light-years wide, and one hundred million light-years thick” (Lerner, 1991, p. 15). These are big objects by any reckoning, dwarfing the 65 million light-years maximum imposed by the Big Bang theory. In order for Tully’s supercluster complexes to form, matter must have moved at least 270 million light-years. That would take between 80-100 billion years (conservatively). “There is no energetic process vigorous enough either to create, in twenty billion years, the large-scale structures astronomers have observed or to stop their headlong motions once they were created” (Lerner, 1991, p. 31). Not only do supercluster complexes dramatically contradict the Big Bang prediction of cosmic homogeneity, they seriously challenge the bed-rock of the theory itself, reducing it to an absurdity. For if Tully’s “complexes” are genuine celestial objects, and not merely observational or computational artifacts, then we are presented with a situation where the 20 billion year-old universe contains objects that are at least 100 billion years old! That’s a real problem. But the situation gets even worse: In 1990, Harvard Smithsonian astrophysicists Margaret Geller and John Huchra not only confirmed Tully’s findings but discovered an even bigger object which they called the “Great Wall”. This is a huge sheet of galaxies, stretching in every direction they mapped, more than 200 million light years across, about 20 million light-years thick, and 700 million light-years long. And then a team of British, Hungarian, and American astrophysicists, including T. J. Broadhurst and David Koo, discovered the biggest clustering of them all—a pattern of galaxies stretching more than 7 billion light-years, spanning a quarter of the diameter of the observable universe. According to astrophysicist Eric Lerner, “The galaxies seem to be moving very slowly relative to one another—no more than five hundred kilometers per second. At that speed, the gigantic void-and-shell pattern appears to have taken at least 150 billion years to form—seven or eight times the number of years since the Big Bang allegedly took place” (Lerner, 1991, p. 25. Emphasis added.) Big Bang Response/Counter-response: As observations such as those just discussed accumulate, and the disconfirming evidence for the Big Bang becomes more difficult to refute, the die-hard response is typically to invent new concepts to stretch and twist the theory to fit the facts. Now, of course, adapting theory to match observation is an integral part of the scientific method, and one of the reasons for its immense success over the past 400 or so years. But there is a difference between theory revision and theory “patchwork”. If a theory is so counterfactual that it requires numerous ad hoc “patches” simply to keep the theory respectable-looking, then it is probably better to throw out the old suit and design a new one that’s a better fit. With the Big Bang theory, we seem to be dealing with such a patchwork of saving postulates (a situation reminiscent of the epicycles upon epicycles added to the Ptolemaic system more than two thousand years ago in attempts to keep it “respectable”, and to fit the anomalous observations of planetary motions.) For example, one response to the problem of cosmic structure is the suggestion that if the matter of the universe were denser by about 25 percent, and spread evenly throughout, then the observed “clumpiness” of matter in galaxies would be only apparent. The idea is that the spaces between galaxies aren’t really empty, they just happen to contain diffuse concentrations of matter that, “for some reason”, didn’t coalesce into luminous galaxies. But as Lerner points out, “This theory is entirely ad hoc—that is, it was invented to bridge the gap between theory and observation. There is no reason to believe that there is a lot of gas in the voids, or that galaxies would not form in this gas. But more to the point, the ‘biased galaxy formation’ theory is contradicted by observation” (Lerner, 1991, p. 26). And this leads us into the next controversial area: • Problem 3: Chemical composition of the cosmos: Observation of galactic spectral red-shifts, reveal their velocities. As galaxies move around super-large-scale objects such as the Great Wall, these measurements can be used to calculate the mass of such objects. The reason is simple Newtonian mechanics: Massive objects attract everything near them; so by observing the velocities of nearby galaxies in the gravitational field of the super celestial objects astronomers can “weigh” them. In 1989, Columbia University astrophysicist E. Shaya did just that, and discovered that the average matter density of the universe is about one atom per 10 cubic meters of space. Big Bang Response: Now, as it happens the Big Bang theory itself predicts the amount and density of matter in the universe. This is because the cosmic abundance of primordial elements helium and two rare isotopes, deuterium (heavy hydrogen) and lithium depend on the matter density of the universe. Greater density of the primordial nuclear soup would mean more lithium and less deuterium and helium. By observing the spectra of light from stars, astrophysicists can accurately calculate the abundance of the elements, and the data show that about 24 percent of the matter of the universe is helium, while deuterium checks in at one part in 100 thousand, and lithium at one part in 10 billion. When these observed relative abundances are matched with Big Bang predictions about matter density, it turns out that the predictions square neatly with Shaya’s observation of matter density of about one atom per 10 cubic centimeters of space. Counter-response. Great! the Big Bang theorists say. Another confirmation of the theory: Observed chemical abundances of helium, deuterium and lithium correspond exactly with the observed matter density of the universe predicted by the theory. But remember the “patchwork” I spoke of earlier. Faced with accumulated inconsistencies between observations and theory, Big Bang supporters have had to resort to a number of ad hoc theoretical patches. Now, for the theory to hold together, these patches must be interconsistent. The patches must join up and the seams must be smooth. Well, as we saw, one of the patches, designed to cover over the problem of cosmic structure (formation of galaxies, etc.), was the suggestion that galaxies could form if the theory assumed an additional postulate that the universe contained 25 percent more matter (spread evenly throughout space). But now we see from the observations of the relative densities of the primordial elements and the observation of the matter density, that there is a perfect match. In other words, there is no room left in the theory for any additional matter, otherwise the relative abundances of helium, deuterium, and lithium would be different. Lerner: “If we accept the idea that there is a great deal more ordinary matter than we see, the basic predictions of the Big Bang as to how much helium, lithium and deuterium are produced are wrong” (Lerner, 1991, p. 27). Furthermore, were these chemical abundances significantly different, stellar formation would have been impossible and we wouldn’t even be here to worry about the consistency or meaning of our cosmological stories. In short, for the Big Bang theory to account for the unmistakable fact that the universe has large-scale structure, it is forced to invent the hypothetical “patch” of additional ordinary matter. But the observed ratios of primordial chemical elements rules out there being any more ordinary matter. Thus, the theory fails to account for the large-scale structure. Another major problem. And this brings is to what is perhaps the most controversial problem of all: • Problem 4: The existence of dark matter. Ninety-nine percent of the universe is missing—this seems to be the prima facie conclusion of the Big Bang theory faced with the observed abundance of matter in the universe, the known strength of the gravitational constant (as understood in both Newtonian and Einsteinian physics), and the observed red-shift displacements/computed recessional velocities of galaxies. As already noted, the density of the matter in the universe is about one atom per 10 cubic meters of space. But this mass density is not nearly enough to allow gravitation to slow or halt the explosive expansion from the primordial fireball and create conditions suitable for the formation of galaxies. We would need about 100 times more matter. But there is no direct evidence for it. Yet, clearly, galaxies do exist, so the “missing” matter must be there too—in the form of undetected, nonluminous dark matter. So goes the standard argument. Big Bang Response: According to the standard theory, galaxies coalesced from the primordial gases as a result of gravitational attraction centered around microscopic fluctuations in the early universe. These tiny perturbations in the primordial soup of particles and radiation were galactic “seeds”, cosmic attractors which served as templates for future galaxies. However, as early as 1967 physicists P. J. E. Peebles and Joseph Silk pointed out that if such primordial fluctuations actually existed, they should show up as corresponding fluctuation in the background microwave radiation. Any unevenness in the matter of the universe in its early days around the 300,000-year mark, should show up as “anisotropies”—irregular hot spots in the 3°K background. Fluctuations that would result in galaxies, they calculated, would show up as temperature variations of around five parts per 1,000. Further studies showed, however, that anisotropy should be as low as one part in a thousand. Such minute variations would be sufficient to support the Big Bang prediction (or “retrodiction”) of primordial fluctuation. However, by the end of the seventies, theorists realized that observations consistently showed that there was no anisotropy—not even as low as one part in 10,000. Some other mechanism was needed to explain the formation of galaxies. If there was more matter than the amount observed, however, the combined effect of the additional matter and minute fluctuations should do the trick. The additional matter, according to calculations, was about 100 times the matter of the visible universe—about 10 atoms per cubic centimeter of space. Cosmologists introduced the concept of the “omega ratio”, where just enough matter to stop the expansion of matter would give omega a value of 1. Unfortunately, calculations showed that the actual ratio was closer to .01 or .02. As time after time observations and calculations showed that there simply wasn’t nearly enough ordinary (that is detectable) matter in the universe to account for the slowing of expansion and for the formation of galaxies, and since galaxies existed, the originally wild notion of “dark matter” gained force. It simply had to be there. So the hunt began. And, as noted earlier, by observing the rotational ve |
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