Measuring Star Radii with General Relativity

Natchanon · Nov 18, 2018

Hi, I'm wondering if it is possible to measure radii of stars using general relativity, given its explanation of gravity as curvature of space.

Thank you

Vanadium 50 · Nov 18, 2018

How would you do this?

weirdoguy · Nov 18, 2018

Natchanon said:

given its explanation of gravity as curvature of space.

Curvature of spacetime, not space.

Ibix · Nov 18, 2018

Natchanon said:

Hi, I'm wondering if it is possible to measure radii of stars using general relativity, given its explanation of gravity as curvature of space.

Are you asking if stars have a well-defined radius in GR? Yes, although you will get different answers depending on how you define radius.

As weirdoguy notes, it's curvature of spacetime, not space. You can't explain gravity just through curvature of space.

Measuring Star Radii with General Relativity

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Measuring Star Radii with General Relativity

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