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Defender's Guide to Science and Creationism
Assertion: Big Bang theory must be false, because something cannot come from nothing

Mark I. Vuletic

Last updated 18 July 2010

Analysis

Creationists who make this assertion assume (i) that Big Bang theory says that the universe came from nothing, and (ii) that is impossible for something to come from nothing. Both of these assumptions are problematic.

(i) Does Big Bang theory say the universe came from nothing?

Big Bang theory uses Einstein's general theory of relativity (just a theory?) to trace the history of the universe back to a moment in time when the entire universe was concentrated in a point of infinite density, called a singularity. This account of the history of the universe is simplified, because it ignores quantum mechanics: at a point in time called the Planck time (now thought to have been 13.7 billion years ago), the universe was small enough to be subject to quantum mechanical effects. To know exactly what impact these effects would have had on the universe before Planck-time would require a theory of quantum gravity, which combines general relativity with quantum mechanics.

We can thus consider from two standpoints the question of whether Big Bang theory says the universe came from nothing: from the simplified standpoint that uses general relativity alone, and from the more complete, but murkier, standpoint that uses quantum gravity.

(ia) General relativity alone. One consequence of relativistic physics is that space and time (unified as spacetime) are themselves inseparable aspects of the universe. Therefore, if we go by general relativity alone, the origin of the universe was the origin of space and time themselves, so there cannot have been time prior to (or space outside of) the initial singularity; indeed, the very idea of "prior to" (or "outside of") the singularity makes no sense. This, in turn, shows that the vision of the universe somehow "coming from" a primordial nothingness, far from being a stipulation of Big Bang theory, is inconsistent with it.

For the universe to have "come from" nothing, it would at least have to be the case that at some point in the past, there was nothing, and then, at some later point in time, the universe suddenly existed. However, as we have seen, Big Bang theory without quantum mechanics entails that the universe existed at every moment of time there has ever been. One cannot in one breath talk about the universe existing at the first moment of time, and then, in the next breath, imply that there was a time before this first moment of time in which nothing existed.

Physicist Stephen Hawking sums all of this up when he points out that

to talk about causation or creation implicitly assumes there was a time before the big bang singularity. We have known for twenty-five years that Einstein's general theory of relativity predicts that time must have had a beginning in a singularity fifteen billion years ago. (Hawking 1993:46)

(ib) Quantum gravity. What happens when one takes into account the importance of quantum mechanics in the early history of the universe? Right now, it is difficult to say, because there is no consensus within the scientific community on a theory of quantum gravity. However, according to physicist Lee Smolin, there are only three possible consequences any theory of quantum gravity could have:

[A] There is still a first moment in time, even when quantum mechanics is taken into consideration.

[B] The singularity is eliminated by some quantum mechanical effect. As a result, when we run the clock back, the universe does not reach a state of infinite density. Something else happens when the universe reaches some very high density that allows time to continue indefinitely into the past.

[C] Something new and strange and quantum mechanical happens to time, which is neither possibility A or B. For example, perhaps we reach a state where it is no longer appropriate to think that reality is composed of a series of moments that follow each other in a progression, one after another. In this case, there is perhaps no singularity, but it may also not make sense to ask what happened before the universe was extremely dense. (Reformatted from Smolin 1997:82)

Possibility A gives us the same situation as that described by standard (no quantum mechanics) Big Bang theory: a universe which exists at every instant of time, and hence cannot have "come from" nothing. Possibility B gives us a universe extending back infinitely in time, likewise eliminating the supposed problems raised by the universe "coming from" nothing. Possibility C (which is the kind of scenario proposed in the quantum cosmological speculations of Hawking 1988) once again gives us a universe that cannot "come from" nothing, as the very notion of time-ordering ceases to have meaning in the early universe.

Apparently, then, under every possible option for a Big Bang supplemented with quantum gravity, it would still be inaccurate to characterize the Big Bang as stipulating that the universe "came from nothing." On each possibility, there is no moment of time at which the universe did not exist.

(ii) Can something come from nothing?

Even were we to assume, against physics, that there was some time prior to the origin of the universe when there was nothing except time, it is unclear what problem this would supposedly raise. There certainly is no logical contradiction in imagining there being nothing at one point in time and then there being something at a later point in time; it is not as though we are talking about "nothing" somehow metamorphosing into an existent something. Although the proposition that something cannot come from nothing (like the proposition that the Earth is flat) traditionally has been a matter of "common sense," it actually (like so much "common sense") reflects only popular prejudice and lacks rigorous logical support. It is not that we know something can come from nothing; it is just that the opposite cannot simply be taken for granted.

(iia) Is something coming from nothing ever observed? One argument against the idea of something coming from nothing is that we never observe such things happening. I suspect this kind of reasoning is always in the back of the mind of the average person, and explains why the idea is so counterintuitive. However, if we are referring to empty space when we talk about "nothing," then it actually is not true that we never observe things come from nothing: the quantum mechanical uncertainty principle allows for particle-antiparticle pairs to appear  spontaneously out of empty space for very brief periods of time. These virtual particles (or quantum vacuum fluctuations) are ubiquitous, and create measurable effects such as the Casimir-Polder force and the Lamb shift. Some physicists have even invoked the same kind of mechanisms to generate theories of the origin of the entire universe from a background of empty spacetime (Tryon 1973).

One can, of course respond that virtual particles do not in fact appear out of literally nothing, because they occur in a background of spacetime in which quantum mechanics operates. While true, this response undermines the claim that we know from observation that nothing can come into existence out of nothing, since the closest thing to nothing that we are ever able to observe is empty spacetime.

One can also argue that perhaps, for all we know, virtual particles are created by God, who chooses, for unknown reasons, to create them in a lawlike fashion, and via means that are invisible to scientists, so that quantum vacuum fluctuations only appear to be spontaneous. This is possible. It is also possible that blunt force trauma never causes anyone to die—rather, what happens is that every time someone's brain suffers appropriate trauma, a hyperdimensional space spider chooses, for unknown reasons, to kill that person in a way that is invisible to scientists, so that things like hammers and bullets, and falls from cliffs, only appear to kill people. The price of taking seriously the possibility of mysterious, invisible causes at the level of a God responsible for virtual particles, is agnosticism about all cause and effect claims. It should be quite understandable that science eschews such things.

(iib) Does something coming from nothing require self-creation? Another argument against the idea of something coming from nothing is that the idea supposedly requires self-creation, which is impossible since nothing can have causal power before it exists. For instance, creationists often assert that to say that the universe came from nothing is to say that it created itself. But this is not so: the idea of the universe "coming from nothing" commits one only to the view that at one time there was nothing, and then at a later time, the universe existed. Talk of causation, much less self-causation, does not need to enter the picture at all.

(iii) Also worth noting

Vilenkin (1982), in an extension of Tryon (1973), has proposed that quantum mechanics alone could allow for the transition of a universe with no geometry (no points) to a universe with a geometry. For the moment, I do not know what to make of this proposal, because I do not understand how one is supposed to parse the idea of a "transition" without time; however, I mention it as something for others to be aware of.

Readers are directed to Guth 1997:271-276 for a brief discussion of proposals by Tryon, Vilenkin, and Hawking.

References

Guth AH. 1997. The Inflationary Universe. Reading, MA: Helix Books.

Hawking SW. 1988. A Brief History of Time. Toronto: Bantam.

Hawking SW. 1993. Black Holes and Baby Universes. New York: Bantam.

Leslie J (ed). 1998. Modern Cosmology and Philosophy. Amherst, NY: Prometheus.

Smolin L. 1997. The Life of the Cosmos. Oxford: Oxford University Press.

Tryon EP. 1973. Is the universe a vacuum fluctuation? pp. 222-225 in Leslie 1998.

Vilenkin A. 1982. Creation of universes from nothing. Physics Letters 117B:25-28.

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