When someone mentions the “Big Bang Theory” today, odds are that anyone in hearing thinks first of the popular television show. Few may realize that the scientific theory known by that name has been around as long as television itself, since the late 1920s, although it didn’t get that distinctive name until after World War Two. Basically, it refers to the idea that the whole universe visible to us today expanded from a hot, dense original state billions of years ago. This is not the same thing as cosmic inflation, the idea that the rate of expansion in the first few “moments” was extraordinarily quick, exceeding even the speed of light. Because inflation has become a standard feature of current cosmological theories, however, the two ideas are often linked together.
The Big Bang nicely accounted for Edwin Hubble’s expanding universe, but it probably wasn’t the dominant view until the 1960s, when the accidental discovery of cosmic microwave background radiation by Arno Penzias and Robert Wilson took the scientific community by storm. The radio noise they found, coming from outer space, was powerful evidence that the universe had indeed begun in a hot, dense state: they were observing remnants of the cosmic fireball that gave birth to the universe. For perhaps the first time in the history of science, someone had found observational evidence that the universe might not have been here forever, suggesting even to some religious sceptics that perhaps the universe had actually had a beginning, after all. The famous remark of the late Robert Jastrow, an agnostic Jew who founded NASA’s Goddard Institute for Space Studies, was not entirely impertinent: “The scientist’s pursuit of the past ends in the moment of creation. This is an exceedingly strange development, unexpected by all but theologians. They have always accepted the word of the Bible: ‘In the beginning God created the heaven and the earth’.” (God and the Astronomers, p. 115 in the first edition of 1978) Prior to that point, to be fair, one could invoke the second law of thermodynamics (http://en.wikipedia.org/wiki/Second_law_of_thermodynamics) to suggest that the universe isn’t infinitely old. A number of prominent scientists had done that, but having empirical evidence for a moment of origin takes the argument to another level. Ted Peters’ essay was written less than twenty-five years after that spectacularly important discovery.
Things have changed somewhat since then, with cosmic inflation and various forms of multiverse theory having been proposed for discussion. Perhaps the most important development happened just a few weeks ago, when astronomers announced the discovery of evidence for the existence of large gravity waves in the early universe; for more information, see here and here.) Gravity waves could indeed account for the observed polarization in the microwave background radiation. They are also linked with theories of cosmic inflation, such that finding evidence for their existence in the early universe makes inflation more plausible. And, in turn, inflation is often linked with the multiverse.
Nevertheless, it’s too soon to bet the house on the multiverse. Although the evidence for gravity waves now appears to be very strong, they are deucedly difficult to observe directly and no one has yet done that. Nor are gravity waves the only possible explanation for the recently observed polarization. More to the point, the surprisingly large magnitude of the polarization eliminates certain theories of cosmic inflation, while keeping others in play. Not all theories of inflation necessarily include parallel universes. According to Science News, “One version [of inflation] that does [predict such large polarization], called natural inflation, was proposed in 1990 by Katherine Freese (now of the University of Michigan) with collaborators Joshua Frieman and Angela Olinto of Fermilab. It would be nice to know if that version predicts parallel universes. Freese says she doesn’t know. But she’s going to get to work on it right away.”
Even if some version of multiverse turns out to be true, it’s still appropriate to ask about a “beginning.” According to the Borde-Guth-Vilenkin theorem, any process undergoing gravitational inflation necessarily had a beginning a finite amount of time in the past. Critics have argued that some possible quantum effects may allow loopholes to the theorem, but with each additional paper the BGV team produces, those loopholes are being closed. So, it still seems that a cosmic “beginning” of some sort is more likely than not: the ultimate question remains on the table.
As an historian of science with quite limited experience at an astrophysics research center, I’m inclined to remain a bit skeptical of the multiverse, even though the recent evidence for gravity waves seems pretty convincing. So far, no multiverse theory has done half as well as the theory of the luminiferous aether, which led James Clark Maxwell, the greatest physicist of the nineteenth century, to predict the existence of electromagnetic radiation—a prediction confirmed experimentally by Heinrich Hertz. In spite of this truly impressive prediction, physicists today no longer believe that the aether exists at all. Why not? No one has ever been able to detect it! Likewise, most forms of multiverse are entirely incapable of being detected in principle, let alone in practice.
Just for the record: I don’t speak for BioLogos on this. We have no organizational view of the multiverse. In his book, The Language of God, published several years ago in 2006, BioLogos founder Francis Collins concluded (p. 76) that the multiverse “certainly fails Occam’s Razor,” apparently by multiplying explanatory entities beyond necessity—an opinion I fully share. That doesn’t necessarily make it bad science: Ockham’s razor is a metaphysical claim about science, not a scientific claim in itself. But, many scientists and philosophers would rather not touch its sharp edge, so it counts for something. On the other hand, some Christian cosmologists think that some type of multiverse might actually exist, and that the idea warrants serious consideration. For pertinent examples, read Gerald Cleaver’s enthusiastic proclamation that God created the multiverse or Don Page’s interesting paper, “Does God So Love the Multiverse?”
Regardless, the Big Bang theory looks better than ever now. In this selection, Peters looks for “consonance” between creation from nothing and the Big Bang.
Consonance with Thermodynamics and Big Bang Cosmology
The last three decades of scientific research [1960s to 1980s] have witnessed increasing support for a cosmology that includes a specific point of origin, the contingency of natural events, an overall irreversible direction of temporal movements, and the forecast of an eventual dissipation or heat death for the cosmos. In particular, the application of the second law of thermodynamics measured in terms of entropy to the macrocosmos leads to the notion of temporal finitude. If the universe in its entirety is moving irreversibly from order to disorder, from hot to cold, from high energy to dissipative equilibrium, then we may draw two significant inferences. First, the universe will eventually die. Even though in far-from-equilibrium sectors or microcosms within the larger whole we will find creative activity and the emergence of new structures, the overall advance of the cosmos is in the direction of eventual dissipation and heat death. Second, the universe must have had a point of origin. It has not always existed. It could not have existed with an infinite past, otherwise it would have suffered thermal death a long time ago. Such scientific speculations open up to intelligibility questions regarding an original creation and a final eschatology.
So also does the theory of an expanding universe, the standard Big Bang model. When we retrace the trail of the expansion backward in time, we eventually find ourselves able to speculate about a point of origin about the beginning of time (not a beginning in time). We can surmise that the expansion we witness today is the result of an explosion which occurred yesterday, a bang which began it all. Astrophysicists believe they have advanced our knowledge to a time as small as 10-35 or perhaps even 10-43 seconds after the very onset of the creative movement.
Furthermore, the complementary research in both astronomy and physics has led to the strong hypothesis that at the beginning the universe was completely singular. [In the period since Peters wrote this, quantum gravity theories, including string theory have been developed to deal with the singularity he refers to. Specific versions of those theories are of course speculative, but physicists now view the singularity as an indicator that classical gravity doesn’t work at short distance/high energy scales, where it must be modified by quantum effects.] The idea of an initial singularity characterized by infinite density and temperature is produced by extrapolating backwards from the currently observed expansion of the cosmos. The bang, or initial singularity, is the event at which space and time were created. Now this marks the end of the line for scientific research, because astrophysicists cannot within the framework of their discipline talk about the singularity, let alone what was going on before it.
We may not be talking about the very beginning, however. We are not yet talking about the “origin” of the original singularity. There are initial conditions which have an ontological (though perhaps not a temporal) priority. The Big Bang model will not permit us to do what Augustine forbade, namely, to ask intelligibly about what was happening before the beginning. Scientifically speaking, we can go as far back as the initial singularity, not to the nothingness which may or may not have preceded it. [SNIP]
We have reached a limit to scientific method. Although we can point to a beginning, it is difficult to say much about it. If scientific explanations are grounded in the principle of sufficient reason, then to speak of an absolute beginning for which there is no explanation is to exceed the boundaries of the method. Thus, a phrase such as “the beginning of the cosmos” must be considered a form of expression which points to the limit of the standard Big Bang theory. Nevertheless, though we can acknowledge the limits of scientific discourse here, we have entered a conversation in which questions of ultimate origin have become intelligible. The principle of hypothetical consonance [this term is explained in the first part of Peters’ essay] does not require that science and theology produce a single coherent worldview at the outset; it requires only that we find sufficient commonality so as to pursue respective questions in an intelligible dialogue. This we have on the question of temporal origin.
By speaking of creatio ex nihilo at this point the theologian can achieve some consonance without appealing to a crass God-of-the-gaps method. It is not the acknowledged limit to scientific conceptuality which is the point of departure here. Rather, it is the material content of the standard Big Bang theory. What we can say is this: the universe as we know it has not always existed in the past. It has come to be. Discussions of creatio ex nihilo make sense. Here the nihilo can refer to two things. It can refer first to the absolute non-existence out of which the divine power may have wrought the initial singularity. It is a specific way in which we might be able to speak of the world’s total dependence upon God its creator. Or secondly, it can refer to nothingness (no-thingness) in the sense of the not-yet-determinedness of things, i.e., it can refer to newness, to the contingent character of the path followed by the bang and subsequent cosmic expansion.
The expansion continues. According to the Big Bang theory, our universe started out very hot and has been in an overall one-way process of cooling off ever since. The temperature of radiant heat declines in proportion to the expanding region of space: double the radius and cut the temperature in half. When the temperature decreases past a certain threshold a so-called “freezing out” takes place. Each freezing out involves the appearance of new forms of matter and energy. At the very hot beginning we did not have such things as molecules, atoms, or even nuclei. [The Big Bang produced an enormously hot fireball that cooled rapidly as the universe expanded. The various components of the physical universe, including subatomic particles, can appear only once the universe is “cool” enough. A given particle is said to “freeze out” when this happens.] These appeared at specific points in the thermal history of the universe. The things (and laws of nature that govern the things) of our universe were produced rapidly but unpredictably: When a volume of water freezes and expands, we know for certain that it will crack. Where it will crack cannot be predicted. In the dissipative macrosystem that is our universe the course of events has been unpredictable.
And, we should note, there is even more unpredictability in far-from equilibrium subsystems within the universe where energy is concentrated so that creative things happen. Our sun and the stars, for example, are centers sponsoring continuing creativity. On the earth, living organisms draw energy from the sun and produce new and higher forms of order. As living beings, we survive by exchanging energy and material with our environment. We might say there is a flow of energy through our bodies which results in a concentration - if not creation - of order. This growth in order is paid for by the dissipation of energy in the wider environment. The negative entropy necessary to support life locally is but an aspect of the net entropy increase cosmically. The results are temporal events of ongoing creativity. To put it as does Ilya Prigogine, chaos within the cosmos is capable of producing new forms of order. [Peters cites Ilya Prigogine and Isabelle Stengers, Order Out of Chaos: Man’s New Dialogue with Nature, p. 12, where they say, “In far-from equilibrium conditions we may have transformation from disorder, from thermal chaos, into order.”] Time brings change, and change brings newness.
What this means is that what exists now is largely contingent, i.e., it is not simply the working out of eternal principles already present at the point of origin. It means, in short, that nature herself has a history. We can on this basis anticipate that things might occur in the future which may be different from those occurring in the past. The events of nature’s history are constitutive of what nature is. Not only can we apply the word “creation” to the point of origin, the primal singularity at the beginning of all things, but it applies as well to the ongoing activity of finite natural events. We may speak intelligibly of both a beginning creation and a continuing creation.
As the closing words of this excerpt indicate, Peters is about to consider two aspects of the doctrine of creation: the traditional notion of creatio ex nihilo (his topic thus far) vis-à-vis creatio continua, the notion favored by many modern theologians that God continues to create long after “the beginning.” In the next excerpt, Peters defends the need for both conceptions. Why not come back in a couple of weeks to see what he has to say?
References and Credits
Excerpts from Ted Peters, “On Creating the Cosmos,” in Physics, Philosophy and Theology: A Common Quest for Understanding (1988), ed. Robert John Russell, William R. Stoeger, S.J., and George V. Coyne, S.J., copyright Vatican Observatory Foundation, are reproduced by kind permission of Ted Peters and Vatican Observatory Foundation. We gratefully acknowledge their cooperation in bringing this material to our readers.
For an up-to-date overview of modern cosmology, see the lucid article by Brian Greene, “Listening to the Big Bang,” Smithsonian 45 (May 2014): 19-26. Those who want to go more deeply into the philosophical questions raised by multiverses that we will probably never be able to observe, I strongly recommend an article by cosmologist George F. R. Ellis, “Does the Multiverse Really Exist?” Scientific American (August 2011) 38-43. At a small conference in Venice a few years ago, I had an opportunity to talk to Ellis for half an hour, while he was writing this very article, and he graciously answered several questions I sent him subsequently. I cannot thank him enough. I am also grateful to Paul Davies, who answered all of my questions about gravity waves in the early universe when I spoke at Arizona State in March, just a few days after the discovery was announced. Gerald Cleaver, Owen Gingerich, and Deb Haarsma provided very helpful comments on this column, but any errors are entirely my responsibility. Astrophysics is like lion taming: don’t try this at home!
Most of the editing for these excerpts from Ted Peters involves removing the odd sentence or two, or in some cases entire paragraphs—which I indicate by putting [SNIP] or an ellipsis at the appropriate point(s). I also insert annotations where warranted [enclosed in square brackets] to provide background information, often citing information from Peters’ own footnotes when it’s important for our readers.