Have you ever pondered if the universe has a boundary? If it did, what does science have to say to back up the theory? Do the metaphysicists agree or disagree with physicists? All these questions and possibly more will be answered in this essay. My goal in this paper is to hopefully convince you that the universe, in fact, does have a boundary and that there is substantial evidence to justify this claim.
I will start off with what the metaphysics has to say about the universe’s “boundaries”. Keep in mind when using the term “the universe”, I am considering not just our sole galaxy, but rather all of the galaxies and space in between, so in other words the collective volume of all galaxies. According to most of the philosophers, the universe is infinite and has no boundary.
Archytas, a Greek philosopher and friend of Plato, is one who argues Aristotle’s model of the universe and believes the universe is infinite. Aristotle’s model of the universe consisted of a closed ball that includes its surface and its interior. Anything beyond the surface of the ball, the edge of space, is absolutely nothing. “Archytas pointed out an obvious problem: couldn’t you stick your hand out beyond space? If that’s possible, then whether or not you do so, there is a place outside where the hand could be – a possible place for the hand. But space is the collection of all possible places of things, and so there must be space outside, and hence no edge at all” (Huggett, p.33). Archytas’ argument suggest that whenever he reaches the edge of the universe (if there is one) and his hand goes beyond the supposed edge, then he just merely ask the same question, infinitely over each time. So Archytas makes a valid ‘what if’ to this conundrum. One way to reject Archytas’ argument is to imagine bounded space which expands every time one attempts to go beyond it. Once you attempt to go beyond it new space would be created, itself bounded. An ever-expanding Aristotle’s model would point out: it always has an edge; it’s just not always in the same place. Another way to get around Archytas’ theory is to imagine a logically possible force field at the edge of the universe. “For there to be an inward directed force that grows infinitely strong at the edges of a bounded space and prevents escape.” (Huggett, p.33) One could also use Henri Poincare’s example to disprove Archytas (Huggett, p.34-35). Archytas himself answered his own question by saying it would be paradoxical if we could extend beyond the edge. The answers to this argument imply that space is bounded in the actual world.
I would like to go in further thought of Poincare’s conjecture. Poincare suggests that the universe is of finite size, it is just expanding infinitely. Let’s set up a hypothetical experiment where you send out a beam of light (a series of photons) out towards the supposed edge of the universe in hopes that it may reflect back or not. As we know, light travels in a straight line and an extremely fast...