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mfb- t1_jarqhow wrote

Reply to comment by ferrdek in Why do cosmologists say that gravity should "slow down" the expansion of the universe? by crazunggoy47

It means spacetime is no longer the simple Minkowski space of special relativity. "Warped" does not mean "expanding". It's more of a local deformation.

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ferrdek t1_jarv0ep wrote

>"Warped" does not mean "expanding". It's more of a local deformation

Lets assume we have some point in space and we travel through it twice. First time the space is empty and the second time some massive object appear on our path (for instance a star) and we travel close to it, going through space warped by its gravity.

is the time needed to travel from point A to point B in warped space longer than time needed to travel that distance through unwarped space? Or the opposite? Or there is no difference?

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mfb- t1_jas94ee wrote

That depends on where A and B are and what your trajectory is in the case with the star.

> Lets assume we have some point in space and we travel through it twice.

If you consider travel from A to B then looking at a single point isn't sufficient.

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ferrdek t1_jasif3h wrote

>That depends on where A and B are and what your trajectory is in the case with the star

The star is located between A and B the trajectory goes through gravitational field of the star. Through space "warped" by the star.

By "point" I mean region of space. English is not my first language, sorry for misunderstandings

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