Stupid Question ™
April 12, 2004
By John Ruch
Q: Did the Big Bang make a noise?
—D.C., Columbus, Ohio
A: What do you mean, “did”?
The Bigness is still Banging, baby! The expansion of the universe continues, with each heapin’ galaxy drifting further from its fellows second by second.
If it was making a noise, I’m pretty sure we’d have heard it by now. (Of course, it did make an electromagnetic “noise” that we can still see echoes of with instruments.) And too bad, because it would have saved all the pencil-pushing it took to notice the Bang in the first place.
The Big Bang is estimated to have begun around 15 billion years ago—give or take a few eons and much sniping in astrophysical journals.
The cosmological theory behind it essentially states two things: The universe a) is continually expanding, b) from some sort of “initial singularity” of energy—a point the size, shape and consistency of which exceeds even my local department store’s pillow collection in terms of varieties invented to suit individual tastes.
You are referring, of course, to the layperson’s cartoonish image of a tiny little universe literally exploding like a firecracker and going ka-blooey all over nothingness.
You should know the term “Big Bang” was coined by the eccentric British astrophysicist Fred Hoyle in a 1950 radio lecture specifically as a slur on what he considered an inane idea. (He was a co-author of the now-discredited steady-state theory, which proposed that universe was, is and will be eternally unchanging because it is continually creating matter at a rate exactly balancing its own expansion. Whew!)
“Big Bang” was too colorful a term to resist, and, like “Quaker” and other one-time insults, was quickly adopted by those who kept the faith themselves. But it’s important to know it was first an insult, because, like all insults, it’s a deliberately reductionist term. The Big Bang is way more subtle and complex than, well, a big bang.
Toss out your conception of a terrestrial explosion, with sound and fury and spherical expansion of debris into a surrounding medium. The Big Bang (presuming the theory correct) was everything expanding into nothing—no medium at all—and not just hurling away in bits but stretching out into all directions, which include well more than our familiar three dimensions.
According to some theoretical models, the expansion did not even necessarily occur simultaneously in all directions, but bulged out here and there at its own pace. In other words, the Big Bang didn’t necessarily start from a single, infinitely dense point, as the first theoretical models indicated.
Also remember that time (at least, as we know it) began only with the Big Bang. The Big Bang was not like the after-effect of a bomb blast occurring at a moment in time. It is the moment of time.
Whittling all this back down to your question, you may recall that sound is simply a vibration carried through a medium. As the Big Bang is not expanding into any medium, it did and does not make a sound. Nor was there sound within the expanding universe initially, because for a good long while it did not contain matter (and later, not enough dense matter) to rub together to create sound.
Thankfully, this allows to utterly bypass the question of whether the Big Bang could make a sound when there was definitely no one around to hear it.