- #36
PeterDonis
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We're not comparing their "realities". They both live in the same reality. In that one reality, the length of the paths that Alice and Bob take through spacetime are different; that is what "different elapsed times" means.Mikael17 said:which parameter is what changes in a gravitational field if you compare Bob's and Alice's reality
Yes, good, you've got it. Except--Mikael17 said:We know that Alice's clock ticks slowing . We know d is the same,
No, the "only possibility" is that Alice's clock runs slow, just as you already said in the quote above.Mikael17 said:The only possibility is therefore purely mathematical that m (the ruler) must also be a relative variable?