![]() ![]() The philosopher David Albert has memorably criticised accounts of the Big Bang which promise to get something from nothing in this way. But perhaps all this really tells us is that the quantum vacuum is (despite its name) a something rather than a nothing. The spacetime vacuum state is seething with particles constantly being created and destroyed, apparently "out of nothing". This may sound like a mathematical quirk rather than real physics, but such particles have been spotted in countless experiments. These fluctuations can give rise to particles popping out, only to disappear shortly after. However, matter and antimatter annihilate in a flash of energy when they meet, meaning these particles were constantly created and destroyed.īut how did these particles come to exist in the first place? Quantum field theory tells us that even a vacuum, supposedly corresponding to empty spacetime, is full of physical activity in the form of energy fluctuations. 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. There was both matter and "antimatter" in roughly equal quantities. 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. 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. 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. 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.īut before we get to that, let's take a look at how "material" – physical matter – first came about. 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. 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. For something to exist, there must be material or a component available, and for them to be available, there must be something else available. My understanding is that nothing comes from nothing. ![]()
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