- #36
NoahsArk
Gold Member
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Thank you for the explanations.
NoahsArk said:I've also seen space-time described many times as like a block.
Umaxo said:Yes, but they would tick at the same rate. All you would see is that the clocks (and all events too) at different places become shifted relative to each other
After you go into sleep one of the clocks moved in any way and come back to the same still position before you wake up. Frame of reference of yours and the clock's coincide when you fall in sleep and wake up.NoahsArk said:Suppose there are two clocks in my reference frame which read the same time, and I go to sleep and wake up and measure that one clock is now ahead of the other.
Of course all reference frames exist at once. They are just mathematical abstractions used in the analysis and have no physical consequences. Any and all of them can be used as desired.NoahsArk said:it also seems like we can conclude that all reference frames exist at once.
A reference frame is a convention for assigning time and space coordinates to events, so what you're calling "switching" frames is just choosing to use a different one. If I say that the top of my chimney is 10 meters above the ground, then a moment later I say that it is 130 meters above sea level... that's what switching reference frames is like.NoahsArk said:Assuming that no one or nothing changed the mechanism of the clocks, then I would have to conclude that I switched reference frames right? If space time switches are possible, then it also seems like we can conclude that all reference frames exist at once. To switch into a new frame, it seems like that frame already has to exist or else there'd be nothing to switch into.
No. You might reasonably conclude that you'd undergone some acceleration.NoahsArk said:Suppose there are two clocks in my reference frame which read the same time, and I go to sleep and wake up and measure that one clock is now ahead of the other. Assuming that no one or nothing changed the mechanism of the clocks, then I would have to conclude that I switched reference frames right?
It's the easiest interpretation and the one with the least philosophical baggage, to my mind. But it is an interpretation, and not a testable claim.NoahsArk said:If space time switches are possible, then it also seems like we can conclude that all reference frames exist at once. To switch into a new frame, it seems like that frame already has to exist or else there'd be nothing to switch into.
NoahsArk said:When I accelerate, though, doesn't that automatically mean I switched reference frames?
NoahsArk said:When I switch reference frames in space time, clocks that were simultaneous go out of sync, so I am actually seeing things different physically
No. Switching reference frames is something you do in your analysis, not physically. You are free to switch reference frames or not after acceleration, as you pleaseNoahsArk said:When I accelerate, though, doesn't that automatically mean I switched reference frames?
No. You only switch reference frames when you decide to stop using one reference frame for your calculations and start using another.NoahsArk said:When I accelerate, though, doesn't that automatically mean I switched reference frames?
NoahsArk said:Maybe a better way for me to have phrased it, instead of saying that "I'm switching reference frames", would be to say that, once I start moving relative to things that were previously at rest in my reference frame, those things are now in a different reference frame.
NoahsArk said:Thank you for the responses. When I accelerate, though, doesn't that automatically mean I switched reference frames?
When I switch reference frames in space time, clocks that were simultaneous go out of sync, so I am actually seeing things different physically (different readings on the clocks, different appearances of things due to more time having elapsed, etc.