Comment by jahnu | Hacker News Reader

Comment by jahnu | Hacker News Reader

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> "The more you move in space, the less you move in time."

Isn't that missing a bit at the end? The less you appear to move in time from a different frame of reference?

We all move through time at exactly 1 second per second, don't we?

For reference: Here's Sean Carrol saying exactly that (but in reply to a different question)

https://www.preposterousuniverse.com/podcast/2021/12/15/ama-...

"...it always goes by one second per second. That’s the only speed at which time can possibly go by, and that’s true whether you’re speeding or staying still or in a gravitational field or not. There’s no such thing as the speed with which we move through space-time, the idea of a speed is the amount of distance we travel as a function of time, that’s what speed is. So it just doesn’t apply to going through space-time, it’s a different kind of thing."

Disclaimer: I’m interested in relativity and have been reading about it lately but I’m no authority.

> We all move through time at one second per second, don’t we?

You need to define “move through time”. The only way to measure time is with a clock, and the clock’s motion relative to you affects the measurement.

If you let everyone define “time” as the thing measured by the watch on their wrist, then everyone moves through time at one second per second, but since people are in motion relative to each other and therefore have different frames of reference, their clocks will measure different times.

Since no frame of reference is privileged, there is no “absolute time”. Of course you could pick one and measure every event against that one, but that would be an arbitrary choice.

This is my understanding. If I’m wrong, I’d be happy to be corrected.

That's my understanding too but I am also saying that "less you move in time" needs to be more rigorously defined. As it stands above I'm not sure it makes sense, even though it might be a useful fiction to get a handle on the weirdness of it all.

I'm also no authority whatsoever on the topic :)

I think Sean Carroll understands Special and General Relativity.

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