I've been asked to comment on an article which states that all memory of what happened before the Big Bang was erased by the brief period of what is known as inflation, just prior to the Big Bang itself. The article in question is not the only one to make this point. It is actually a very interesting topic in several ways and raises two immediate questions: what does the inflation model tell us, and how likely is it to be correct?
Looking in depth at the Big Bang left a few anomalies for cosmologists. Therefore, a model was proposed which removed some of those anomalies. The idea was that just before the Big Bang, a tiny fraction of a second after the beginning of space and time, the size of the Universe grew massively over another tiny fraction of a second. This growth is called inflation. After that incredibly brief period of rapid expansion, inflation switched off and the Big Bang itself took over, with a much slower rate of growth of the Universe. What happened during inflation is said to have provided the starting configuration for the Big Bang itself and many people have written that it is not possible to work out what happened before that. Of course, that doesn't stop physicists from wanting to know and trying to come up with methods to find out.
The biggest problem with inflation as a model is that there is no clear cause for it and there is no obvious reason why it stopped - the physics involved is currently quite vague. It does, though, provide a means of ironing out several problems with the Big Bang, which is why it is taken seriously. Of course, if inflation did really remove all means of knowing what happened before, trying to find its cause is a meaningless exercise. We would then be left with all sorts of possible scenarios which can never be tested: time and space began an instant before the inflation; or space had been growing exponentially forever (inflating since infinitely before the Big Bang) until the final stage of inflation occurred, which is the only part that left any record for us; or perhaps our Universe grew out of the collapse of a previous one. There are other feasible variations around this theme, but if the final moments of inflation wiped out all memory of what came before, then we shall never be able to investigate. I can't imagine cosmologists giving up on such an intriguing quest in a hurry and until the case is proven to be hopeless.
We need to remember, though, that all this presupposes that the Big Bang and inflation did actually take place. At the moment, given the physics we know and the observational evidence, an inflation-Big Bang model fits the data better than any other scientific theory. However, there is a huge amount that we don't know, about which I have written before: dark matter and dark energy are thought to account for vastly more of the Universe than what we do know about, and if we ever end up unifying all of the fundamental forces, that could revolutionize physics even more than quantum mechanics and relativity did in the early 20th century. Who knows what that might end up meaning for our understanding of the origins of the Universe? I think that, however much there is always a temptation to hold onto what we already know, we have to accept that a fully unified description of the fundamental forces and an understanding of dark energy and dark matter could well totally rewrite scientific cosmology. We could even end up losing the Big Bang forever.
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