Antimatter

I agreed to give a public lecture on science and religion here at WIT next week, as part of the SophiaEuropa Research Project on Culture, Technology and Religion. I’ve decided to talk about the Big Bang model - after all, the origin of the universe is a topic of interest to most people, and it’s interesting to consider whether science and religion converge or diverge in their approach to the topic.

How to go about it? I think I’ll start with an overview of the physical evidence for the Big Bang model, and touch on the theoretical framework in which it rests. Then it’ll be fun to consider how the singularity problem fits with models of Christianity. A few points I’ve noticed in my reading around I think I’ll touch on…

1. Philosophers and theologians tend to consider scientific models as if they were pure theory, ready to be overturned at any moment. I don’t think this is right as it ignores the role of evidence in the scientific method. Modern science is often incomplete, but rarely downright wrong (for example, the evidence suggests that general relativity is a more accurate theory of gravity than Newton’s Universal Law, but we send men to the moon using Newtonian gravity and it works fine). Because the scientific method is based on evidence that doesn’t go away, new theories do not ‘overturn’ old ones, they broaden and deepen them.

2. Another common misconception is the ‘fine-tuning’ of nature: it is amazing that all the various constants of nature are so suitable for the universe and life on earth to have evolved as it did. But this should never be stated without some reference to ‘unification’ - as physics progresses, we discover more and more arbitrary parameters turn out not to be independent, but deeply related to a tiny number of fundamental parameters (for example, where we once thought there were four fundamental ‘forces ‘of nature, each with it’s own coupling constant, modern theory predicts that there was probably one fundamental force, that gradually split off into four..)

3. You might think the’singularity’ fits very well with the Christian view of a creation and a creator - and so it does at first sight. But one must consider the predicitions of modern theory carefully..

(i) The ‘before’ problem’: according to the modern theory of gravity, classical general relativity (no allowance for quantum), there is no ‘before’ the bang. This is because space and time , matter and energy, all began at a singularity (Hawking /Hartle theorems show unequivocally that relativity implies that an expanding universe began as a singularity). If there is no ‘before’, it’s hard to see how the creator creates. (Don’t forget there is an awful lot of experimental evidence that relativity is correct, if incomplete)

(ii) However, there is a get-out clause - once the universe shrinks within the size of an atom, quantum physics will come into play, and physics simply doesn’t don’t have a good description of what happens to gravity at these scales

(iii) The ‘first-cause’ problem: on the other hand, quantum theory creates it’s own problem for the ‘first-cause’ argument - it is simply not true in quantum physics that everything has a cause. Tiny particles of matter/antimatter routinely spontaneously appear and annihilate without any cause, so long as the time interval is short enough (it’s a consequence of the Heisenberg Uncertainty Principle, and there is v strong evidence form particle physics that this effect really exists).

(iv) The ’something from nothing’ argument: where did all the energy come from? My favourite answer to this is that it didn’t - for all we know, it’s possible the total energy of our universe could add up to zero, if we include the effects of negative potential energy or vacuum energy.

Indeed, putting relativity and quantum together, one has the modern theory that the birth of the universe may have been a quantum fluctuation, inflated to the size of the universe. This idea must must be taken seriously as more and more evidence for inflation is becoming available!In summary, I think I’ll try the tack ‘let’s see how far we can push science without invoking a creator’, and conclude with Hawking’s observation…” God might be like the Queen and parliament - you can have royalty if you like, but it’s not strictly necessary!…”