Thursday, May 11, 2017
--- Notes on time ---
Time is the number of motion with respect to earlier and later.... Not only do we measure the movement by the time, but also the time by the movement, because they define each other. The time marks the movement, since it is number, and the movement the time.
Well, that was Aristotle's conception of time and it is mine - at least my naive conception. That's the time that's in our heads by which we measure our world, but there is also an element in the world, regardless of what we think, or, even, whether we are.
The environment the human mind developed in was shaped in certain ways by certain forces. These, in turn, shaped the human mind. Causal chains are important to survival, so we have been trained over eons to pay attention to causal chains; therefore, time runs in one direction - forward along causality.
What would happen if time ran backward? Things would undo, including our perceptions, and as soon as it ran forward again, it would "redo" and we could never know that time ever ran in any direction but forward.
Physics calls entropy "the arrow of time" because things run from high usable energy states to states in which all the usable energy is used up. But that's not quite right because there are systems that make entropy go in reverse - that increases usable energy in the environment, albeit only temporarily, and we don't see this reversed entropy as time-running-backward. Neither does time run backward in Einstein's world of four dimensions when entropy is reversed.
Currently, unless we cross some barrier that can carry us beyond what we are wired to perceive/conceive the only way to grasp the element of time that is independent of our sense and of us is to trust the mathematics that tells us that there is something out there that we can't grasp but must be there because, otherwise, nothing would work right.
More and more, physics looks strangely like philosophy.