time to think : memes

[+] stebo02@lemmy.dbzer0.com 1 points 1 month ago* (last edited 5 days ago) (1 children)

[deleted]

[–] Aux@feddit.uk 3 points 1 month ago

There are two ways of looking at it.

The time machine is using itself as a point of reference to comply with general relativity. The only way to time travel is to move forward in time. The way to move through time would be to move a lot faster than the Earth, so that every minute for you inside the time machine would equal to many years for earthlings. And if you're moving that fast you'll fly away from Earth.
The time machine somehow has a knowledge of the whole universe, this way a Newtonian model applies and an absolute point of reference exists. That allows unrestricted travel both forwards and backwards in time, but that also means that the Earth will inevitably move from under the machine to follow its path across the universe.

No matter how you twist it you'll end up all alone in space. You need a machine which can move through both time and space at the same time.

[–] 0ops@lemm.ee 0 points 1 month ago (1 children)

We can't really say that for certain. The word "space" as we know it means nothing without the idea of relativity. Earth orbits the sun, the sun orbits the center of the Milky Way, which exists in a nest of clusters and super clusters ... and then you get to the edge of the visible universe. My point is, if a universal frame of reference exists, we haven't found it. "Absolutely stationary" isn't something we can test for. Everything that we can observe appears to be moving around something, so can we even responsibly assume that there is a universal frame of reference? Or is it safer to assume that relativity all that there is (i.e. space-time has no boundaries)?

[–] Aux@feddit.uk 1 points 1 month ago

I've explained it in another reply. It's not about being "stationary".

[–] Fluke@lemm.ee 0 points 1 month ago* (last edited 1 month ago)

That isn't possible. Time is as part of space as the other dimensions. Time is distorted by mass, just like space.

You can't move "purely on the Y axis" any more than you can move "purely on the time axis", or vice versa.

Off topic: Why is it a new idea that the observed motion of the universe around us is affected by "faster time" in denser areas of space? Why is that not blindingly obvious? Bwuh?

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