What existed before the Big Bang? – BBC News

My understanding is that nothing comes from nothing. For something to exist, there must be material or a component available, and for them to be available, there must be something else available. Where did the material come from that created the Big Bang, and what happened in the first instance to create that material? Peter, 80, Australia.

"The last star will slowly cool and fade away. 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 fading of that last star will only be the beginning of an infinitely long, dark epoch. All matter will eventually be consumed by monstrous black holes, which in their turn will evaporate away into the dimmest glimmers of light. Space will expand ever outwards until even that dim light becomes too spread out to interact. Activity will cease.

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.

The first matter

But before we get to that, let's take a look at how "material" physical matter first came about. 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. 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. But that understanding doesn't address the question of whether something came from nothing.

So let's think further back. The first long-lived matter particles of any kind were protons and neutrons, which together make up the atomic nucleus. These came into existence around one ten-thousandth of a second after the Big Bang. Before that point, there was really no material in any familiar sense of the word. But physics lets us keep on tracing the timeline backwards to physical processes which predate any stable matter.

This takes us to the so-called "grand unified epoch". By now, we are well into the realm of speculative physics, as we can't produce enough energy in our experiments to probe the sort of processes that were going on at the time. But a plausible hypothesis is that the physical world was made up of a soup of short-lived elementary particles, including quarks, the building blocks of protons and neutrons. There was both matter and "antimatter" in roughly equal quantities. Each type of matter particle, such as the quark, has an antimatter "mirror image" companion, which is near identical to itself, differing only in one aspect. However, matter and antimatter annihilate in a flash of energy when they meet, meaning these particles were constantly created and destroyed.

See the rest here:

What existed before the Big Bang? - BBC News

Related Posts

Comments are closed.