Eternalism and Presentism - theories of time

Eternalism and Presentism -- theories of time

The topic of this thread emerged from this thread, [thread=289962]A problem with time travel[/thread]

Originally posted by Maxtm
You and I can perform experiments which show that we are not in the same Present, that we do not share a Now.

How does Presentism hold against that simple truth?

I was having a conversation with my girlfriend about time earlier.

We were driving home from somewhere, and I told her "We are already at home, upstairs, changing into our leisure clothes. We are still at the book store, beginning this conversation. We are still in the moment where I began telling you this."

Then, when we got home, I continued "We are still back there at the corner, when I said we are already upstairs changing, and we are upstairs changing. We are still at the book store, we are still in the moment when we first met. We can't see these periods of time because they are... around the corner from us. That does not invalidate them, nor does our inability to directly perceive events we clearly remember in our past make them stop existing. You and I are lines scribbled through time, imagining each snap shot we perceive to be the truth of reality."
How do I know that you're not just a closet presentist masquerading as an eternalist? :smile:

Your statements don't make any sense to me, so far. (They seem to contradict SR's definition of time.) I'm here to learn, so please elaborate.

What do you think the word, time, refers to? How would you define it?

Are your statements based on an interpretation of general relativity?
Re: Eternalism and Presentism -- theories of time

Time refers to a direction.

I would define it as an ironic degree of freedom, in that it has directions one can move along in theory, but we are constrained by our mass to one of those directions.

Rather like a pawn on a chessboard, we know the other squares exist, but are limited to a single general orientation to our progress.

Like knowing left and right exist while standing sideways on a treadmill. You are aware there is a potential freedom of movement to your left, but you are constrained to move to the right with the treadmill.

You can move back and forth across it, which will reduce the distance you move to the right accordingly, but without some ability to overcome your own inertia, you cannot move across the surface fast enough to go to the left.

A true 4 Dimensional view of your path would be a line extending along the treadmill surface, meandering back and forth through the dimensions you are free to traverse. While you yourself only see 3 D slices of that line, labeling them as a sequence of Nows.

Yes, it is based on GR.

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