It’s hard to imagine not existing in the future. Logically, we know it will be true, but it’s hard to actually wrap your head around. People of many religions sidestep this mental problem by thinking that we don’t end. Our soul, and I suppose consciousness, continues on in an afterlife, or reincarnation, etc. If one does not have that, wrapping your head around not existing in the future is a little like thinking about the edge of the universe. Where does it end? How does it end? Is there a brick wall at the end? Actually, the answer to that question is that the universe does not have an edge, it does not have a center either. Every place in the universe is just as close to the edge (there is none), or just as close to the center (again, none), as any other place in the universe. The fourth dimension is time. The universe is expanding at the speed of light from a central point in time. I don’t see how these two conundrums are related, perhaps that could be the subject of some deep mystical thinking that you all could help me with, but the feeling is a little the same.
The best analogy that I have heard to imagine the size and non end of the universe is to think about a balloon that is being blown up. Imagine everything in the universe, including all three dimensions of space, existing on the surface of this balloon and the balloon is expanding, or blowing up at the speed of light. In other words, imagine all stars and galaxies are drawn on the surface of this balloon in ink. The radius of this balloon is the time since the Big Bang. The universe is not infinite, as the surface area of this balloon is not infinite, but you can not get to the other side of the balloon because the farthest reaches of the universe (balloon) are going away from us at the speed of light, and it is impossible to go faster than the speed of light. I love Star Trek, but don’t listen to them, not possible.