Re: What is time?

Mike:

Here's something quite obvious I'm now starting to understand better thanks in part to your post: We are all connected. The whole universe is one. There is no true separation or isolation.

You have a slightly different take on time than I have had when you question its existence as a dimension. I have sometimes wondered if maybe the three spatial dimensions we observe are generated only by time. If you have 4 dimensional "raw" spacetime and add an "arrow," a vector in R^4 if you will, which you call time, then it will define the spatial component of spacetime as the set of all vectors orthogonal to time. In other words, just like when you're floating in outer space, you can call any arbitrary direction "forward," but once you do that, both "right" "up" must be orthogonal to "forward" in order to get the usual system of coordinates I'm sure you are familiar with. They are confined to a plane. If you create a 4-dimensional universe and give it time, you thereby confine space to a certain 3-dimensional hyperplane within it.

At some point, I even tried to carry this thought one step further: What if our concept of orthogonality is only created by the existence of time. Time might even define our concept of dimension since it is the only "natural" one-dimensional aspect of the universe. In other words, maybe the only reason we can observe three spacial dimensions is because they are fundamentaly similar to time.

This brings us full circle to the question: How could space ever be observed without time? Isn't the only reason we know of up and down that something can move upward or downward? If nothing could ever move, I doubt we would be able to develop the concept of space.

All these thoughts seem awfully reminiscent of the old chicken-egg-question, just with more players. Instead of chickens and eggs, we have (at least) time, motion, and space.

Phil Tweet