Monday, 25 March 2013

A tale of two universes?

One sometimes runs into discussion with philosophers and religious people about the nature of vacuum and the origin of the universe. These people tend to instinctively always discuss about a vacuum we know nothing about and have never seen or observed - I'll call it the Aristotelian vacuum. It is a state of absolute absense of everything. Though often ill defined in a sense that it is undefined if it is also in a state of absense from time and space. The actual vacuum we know of is the quantum vacuum, a region of spacetime which exists in a minimum energy state and from which no energy can be extracted, but in which the laws of physics apply, mainly the theory of relativity and quantum mechanics etc. That sort of vacuum has been observed and it is the only kind of vacuum we know of. This is a very important distinction.

The way science works is that we open our eyes and observe what we see around us. Then we give names to our observation and plan our lives according to what we've observed. I think therefore I am. Anything else is at a distance from me. The thing is, quantum vacuum basically explains and predicts the universe and our observations so far. Aristotelian vacuum exists nowhere that we know of and explains nothing. It is also unclear if such a vacuum makes any sense, regardless if it includes time and space. Some questions are also very ill defined, what was before the big bang? Big bang is the edge of time and space, or one might say time began so the question doesn't make any sense. Did the Universe always exist? Yes, in fact it did, because always is context dependent on time and if time is part of the universe then as much as there is always to be had, it did exist. Additionally, we simply cannot see and therefore speak of anything outside the universe.

Now then there's the story of the two universes? What's that all about? The lowercase universe is the observable universe, all the galaxies and all the matter, energy, space and time, the laws of physics etc. that we know of. A diameter of approximate 93 billion light years and roughly 14 billion years of time. Over 100 billion galaxies each containing around 100 billion stars. The capital Universe on the other hand is commonly defined as the totality of all existence. All the parallel universes, multiverses, omniverses, branes, cycles and whatsamacallits. All the dimensions and all the information we may ever dream of. If there exists such a thing as god (which I don't believe), it is by definition part of the Universe and at most the Universe.

There may become a day when the universe is equivalent to the Universe, but as of today we aren't there yet. It may be that the Aristotelian vacuum is part of the Universe even when it is not part of the universe or it may be that the concept of Aristotelian vacuum doesn't even make sense. Equivalently, god is a concept which might in principle perhaps be part of the Universe in some form, or at most be the Universe, but it is most certainly not part of the universe (now), simply because of the way the universe is defined. Though I do believe that god most strictly speaking is a contradictory idea, and even when defined more loosely is unlikely to exist in the Universe or be a coherent (to the idea) concept. The nature of quantum vacuum on the other hand is such that it is part of the universe since it has been observed, it also seems to explain the universe, however very fundamental property of quantum vacuum, the quantum fluctuation is not identifiable, so we must conclude that it must by definition reside outside the universe (but within the Universe). What makes quantum vacuum a very unique thing is that it is the only so fundamental thing we know of which requires an explanation in this universe and obviously has its explanation outside of the universe. Why do I say such a thing? Because quantum fluctuations are not causal, they are the only thing which don't have causally identifiable origin, and have basically been conclusively demonstrated not to have one but are yet observable.

God exists outside of time and space? He is changeless? Isn't the first almost the definition of nonexistence, even at best it would only mean he exists in some other time and space. The second certainly the definition of mindlessness.

However, to conclude, there are things we've seen and continue to see, but can't explain. That is science waiting to be done. Then there are things only some people have seen, but can't point out to others and may or may not continue to see, that something is most often religion.

No comments:

Post a Comment