This takes us to the so-called “ grand unified epoch”. But physics lets us keep on tracing the timeline backwards – to physical processes which predate any stable matter. Before that point, there was really no material in any familiar sense of the word. These came into existence around one ten-thousandth of a second after the Big Bang. The first long-lived matter particles of any kind were protons and neutrons, which together make up the atomic nucleus. But that understanding doesn’t address the question of whether something came from nothing. We do in fact have a pretty detailed understanding of how the first atoms formed out of simpler particles once conditions cooled down enough for complex matter to be stable, and how these atoms were later fused into heavier elements inside stars. If we are aiming to explain the origins of stable matter made of atoms or molecules, there was certainly none of that around at the Big Bang – nor for hundreds of thousands of years afterwards. The first matterīut before we get to that, let’s take a look at how “material” – physical matter – first came about. Or will it? Strangely enough, some cosmologists believe a previous, cold dark empty universe like the one which lies in our far future could have been the source of our very own Big Bang. Space will expand ever outwards until even that dim light becomes too spread out to interact. All matter will eventually be consumed by monstrous black holes, which in their turn will evaporate away into the dimmest glimmers of light. The fading of that last star will only be the beginning of an infinitely long, dark epoch.
With its passing, the universe will become once more a void, without light or life or meaning.” So warned the physicist Brian Cox in the recent BBC series Universe. “The last star will slowly cool and fade away.