Often when considering the origins of the universe, we have to contend with the question: What caused the Big Bang? On the face of it, it’s a good question. It is, however, somewhat misleading.
For the theologically-minded, it’s an easy one to answer: God did it. But, this answer isn’t particularly satisfactory given what we now know about the nature of time, i.e., that it is a product of the universe.1 Space-time has been discovered to make up the fabric of the universe, providing the dimensions in which matter and energy can exist. So, when we ask, ‘what caused the Big Bang?‘ we’re faced with a significant conundrum.
Causality works in a chain between antecedent and consequent. The antecedent comes prior to, and causes, the consequent. The antecedent must come before the consequent, or else the chain of causality is broken – causality is therefore a chain through time. This makes it difficult to ask what caused the Big Bang because how can something cause the beginning of time if there is no time in which to cause it?
One answer is to posit the existence of a dimension analogous to time existing independently of the universe. Supposing that our universe was a constituent member of a much larger multiverse – the multiverse might have within it some similar property that enables causality to take place. In such an environment, our universe could have been caused by an antecedental event in the multiverse. This answer, though interesting, is not the complete answer though, as it simply pushes our problem back one more step, as we can see when we ask, “what caused the beginning of the multiverse?”
Another answer is the one I mentioned before, that God created the universe and time along with it. This suffers from the same difficulty as the last question though – we must invoke some divine analogue for time for God to operate in (he must be able to exist and act ‘before’ time has been created). It also receives the same criticism: If we explain the beginning of the universe by appealing to God, then how do we explain the origin of God? If the universe requires a beginning to be explained, then God ought to also, and if God is immune to questions of a beginning, then why not the universe? It is simpler to say that the universe has existed forever than it is to say that the universe has existed finitely and that there is a God who has existed forever.
The simplest answer might be to suggest that it’s not necessary for causality to exist everywhere. When this idea is mentioned, people usually imagine the universe spontaneously popping into existence, but this might not necessarily be the case. If there is no ‘before’ the universe, then there is no time for it to come into existence. Instead, we have to be more creative and imagine a scenario in which there has only ever been the universe. It does not require a cause, because it did not have a beginning to be caused. Asking, “what caused the Big Bang?” then becomes a non-question, like asking “what is the purpose of rock?” There simply might be no answer – a difficult concept for people who live in a world of causality.
The difficulty with this explanation is that we can trace back antecedents and consequents, theoretically, until the very first one. We know that time dates back to the Big Bang – it therefore stands to reason that there ought to be an initial antecedent, a First Cause.2 If that’s the case, then we must admit that nothing caused the first cause, since it is the first. How it could have come about is an unsatisfying mystery.
We must nevertheless be careful when talking about causation as it relates to the origins of the universe, and where we can we should do our best to avoid easy answers to difficult questions. We might never know the answer to whether the universe was caused or not – its boundaries could well be quite impenetrable. Still, we can try.
This has been known since the acceptance of Einstein’s theory of special relativity, which introduced the concept of temporal subjectivity – the idea that time where I am can be moving at a different speed to time where you are. ↩
The idea of the First Cause was first written about by Aristotle. He argued that if the universe had a beginning, then it must require an ‘efficient first cause’. That which caused the First Cause was termed Primum Movens, or the Unmoved Mover, and often assumed to be a deity. The cosmological argument is the name for arguments attempting to explain the First Cause, and these have been taken up by many philosophers and theologians over the ages, notably Thomas Aquinas, who in his writing referred to the First Cause as prima causa. ↩