How Can Time Be Relative While the Speed of Light Remains Absolute?

Star786
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I'm really confused!
How can time be relative and speed of light absolute?
If you were moving a long with speed, whilst someone else was stationary would you not measure light to be slower??
 
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I will take the two questions in reverse order. "If you were moving a long with speed, whilst someone else was stationary would you not measure light to be slower?? "
No.

"How can time be relative and speed of light absolute?"
Do you have any reason to think that the speed of light is relative and time is absolute? People only have problems with this because the opposite is intuitively obvious to them. Unfortunately, when it comes to things we do not have everyday experience with, what is and is not intuitively obvious is irrelevant. There is no reason why nature would behave in a way that we can understand. If you are going to think about physics seriously, it is something that is worth getting used to.
 
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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