Friday, 25 October 2013

Much Ado About Nothing

Just to be clear, this is about what was there before the Big Bang, not Elizabethan literature!

What is nothing?

If I have an empty box, what is inside it? Nothing! Well, that is the simplistic answer, but in fact the box is full of air.

Let us suppose inside we have a glass vessel that we can pump all the air of, is there now nothing inside it? Is a vacuum something? I am going to assume not, but light can travel through the vessel, so it does contain photons.

So have an opaque, evacuated vessel. What does it contain now? A gravity field for one thing. Electromagnetic fields will be slight, but there will be present.

Looks like we have to move our thought experiment to intergalactic space, and to suppose that only only is nothing here, but there is also nothing for an extremely long distance, and electromagnet and gravity fields are essentially zero. This surely is nothing...

Still no. Quantum fluctuation leads to spontaneous production (and subsequent destruction) of virtual particle pairs, so even here there is not really nothing.

All this has lead philosophers to devise their own definition of "nothing"; a philosophical "nothing" has no virtual particles, it has no physicals laws and it does not even have the potential to later produce any of these things.

Now, this post is about what there was before the Big Bang, and one thing we can be sure of is that this philosophical "nothing" was not it. It cannot be, because that is built into the definition; it is something (as it were) from which nothing can appear. And clearly stuff appeared.

Unfortunately this philosophical sense of "nothing" has been used to justify some bad arguments

Nothing to the Kalam cosmological argument

Here is WL Craig:
Vilenkin's recent book is a wonderful popular introduction to contemporary cosmology. It contains provocative discussions of both the beginning of the universe and of the fine-tuning of the universe for intelligent life. Vilenkin is a prominent exponent of the multiverse hypothesis, which features in the book's title. His defense of this hypothesis depends in a crucial and interesting way on conflating time and space. His claim that his theory of the quantum creation of the universe explains the origin of the universe from nothing trades on a misunderstanding of "nothing."
What Craig is doing is forcing this philosophical "nothing" on Vilenkin, and then viewing Vilenkin's argument through that filter. Vilenkin patently does not intend that particular definition of nothing. We know that because Vilenkin is talking about a type of "nothing" that does spawn stuff, but in fact Vilenkin is on record saying just that:
As such, there is some probability for the universe to pop out of “nothing.” You can find the relative probability for it to be this size or that size and have various properties, but there will not be a particular cause for any of it, just probabilities.

I say “nothing” in quotations because the nothing that we were referring to here is the absence of matter, space and time. That is as close to nothing as you can get, but what is still required here is the laws of physics. So the laws of physics should still be there, and they are definitely not nothing.
Craig frequently invokes Vilenkin to support his claim that the universe had a beginning as part of his Kalam argument. This makes it clear that the Kalam argument fails. If Vilenkin is correct, then the universe must have had a beginning, but prior to the universe there could be an absence of stuff that engendered the universe - no need to invoke God.

A Universe from Nothing?

Vilenkin is not alone in using "nothing" to mean something other than the philosophical nothing. Kruass published a book "A Universe From Nothing", and clearly he too is using "nothing" in a different way to the philosophers.

Christian apologists object too, but they are just riding coattails.

That second link actually tries to use a dictionary definition to show Krauss is wrong!

Edward Feser

Philosophers too have objected to Krauss' use of the term. This is by Edward Feser, an associate professor of philosophy:

.... There is a lot of farcical chin-pulling in the book over various “possible candidates for nothingness” and “what ‘nothing’ might actually comprise,” along with an earnest insistence that any “definition” of nothingness must ultimately be “based on empirical evidence” and that “‘nothing’ is every bit as physical as ‘something’”—as if “nothingness” were a highly unusual kind of stuff that is more difficult to observe or measure than other things are.


The bulk of the book is devoted to exploring how the energy present in otherwise empty space, together with the laws of physics, might have given rise to the universe as it exists today. This is at first treated as if it were highly relevant to the question of how the universe might have come from nothing—until Krauss acknowledges toward the end of the book that energy, space, and the laws of physics don’t really count as “nothing” after all. Then it is proposed that the laws of physics alone might do the trick—though these too, as he implicitly allows, don’t really count as “nothing” either.

Feser has decided what "nothing" means, and has further decided that everyone else MUST use his definition - because, you know, he is an associate professor of philosophy, God damn it!

Do associate professors of philosophy get to decide how a term is defined in physics? Not as far as I am aware

And yet, when we strip away this rather arrogant claim, what are we left with? As Feser says: "The bulk of the book is devoted to exploring how the energy present in otherwise empty space, together with the laws of physics, might have given rise to the universe as it exists today." I would be intrigued to see how Feser, or indeed the whole of Christianity, explains how that process proceeded.

Feser is an atheist-turned-Christian, so certainly has an axe to grind here. What he is doing is insisting that atheists come up with an explanation of how stuff can come from nothing, when he defines nothing as that from which stuff cannot come. Basically, he is rigging the game. Why would a philosopher have to stoop to that to maintain his faith?

No comments:

Post a Comment