Does Time Exist at Absolute Rest or Light Speed?

LawrenceM
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I'm hoping someone is willing to help me with this question.

Time is well explained when observed at point between absolute rest and c. The faster an object travels through the dimension of space, the slower that object travels through the dimension of time. Fair enough.

Does this mean that the dimension of time only pops into existence when an objects that has mass moves at a rate somewhere between absolute rest and c? Is the dimension of time "absent" at both extremes (absolute rest and c)?
 
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You are forgetting that velocity is a relative concept. Something can only be at rest relative to something else, or moving at velocity v with respect to something else. Your statement:
The faster an object travels through the dimension of space, the slower that object travels through the dimension of time.
Applies with repsect to an observer in a different frame of reference. However, an observer in the same frame as the object obviously experiences time to move at the same rate. The only velocity that is truly irrespective of observers is c, since it is measured the same for all of them.

I think this should clear up whatever questions you have about this.
 
wow, that was fast - and thank you. So everything that has mass is in motion and experiences time. Differences in time and speed are relative to the frame from which they are being observed. So is asking about absolute rest sort of like asking about the beginning of time? Or like asking what’s north of the north pole again ;)
 
Well asking about an object which is absolutely at rest is actually a meaningful question with a meaningful answer. Simply put, nothing can be absolutely at rest because there always exists a reference frame such that this object is in motion.

I'm not sure where you're going with the beginning of time bit, but it seems a little irrelevant to the discussion here.
 
You’re right of course. The beginning of time comment isn’t relevant. What I meant to say is that there’s no point in me wondering about perspective from reference frame of absolute rest because, as you helped me understand, everything with mass is in motion from at least one other reference frame. As an amateur, I was trying to imagine how time and space might be perceived from an object that was in a true state of absolute rest. You’ve helped me understand why there's no such thing.
 
I asked a question here, probably over 15 years ago on entanglement and I appreciated the thoughtful answers I received back then. The intervening years haven't made me any more knowledgeable in physics, so forgive my naïveté ! If a have a piece of paper in an area of high gravity, lets say near a black hole, and I draw a triangle on this paper and 'measure' the angles of the triangle, will they add to 180 degrees? How about if I'm looking at this paper outside of the (reasonable)...
From $$0 = \delta(g^{\alpha\mu}g_{\mu\nu}) = g^{\alpha\mu} \delta g_{\mu\nu} + g_{\mu\nu} \delta g^{\alpha\mu}$$ we have $$g^{\alpha\mu} \delta g_{\mu\nu} = -g_{\mu\nu} \delta g^{\alpha\mu} \,\, . $$ Multiply both sides by ##g_{\alpha\beta}## to get $$\delta g_{\beta\nu} = -g_{\alpha\beta} g_{\mu\nu} \delta g^{\alpha\mu} \qquad(*)$$ (This is Dirac's eq. (26.9) in "GTR".) On the other hand, the variation ##\delta g^{\alpha\mu} = \bar{g}^{\alpha\mu} - g^{\alpha\mu}## should be a tensor...

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