Why Doesn’t Gravity Happen Instantly?

Re:Why Doesn’t Gravity Happen Instantly? by rolph on Friday December 18, 2020 @10:58PM (#25474881)

the speed of light is perhaps a convenient benchmark.

light has no resting mass thus is not limited to sublight speed due to this lack of mass.

in this scenario the limitation is about the maximum deflection/distortion rate of spacetime, thus spacetime distortion can not occur at a rate faster than light speed.

if spacetime is distorted beyond this curvature you get a black hole, and if a blackhole is smaller than the schwarzschild radius it spontaneously collapses and backlashes into ultrahigh energy photons[gamma rays]

https://en.wikipedia.org/wiki/Schwarzschild_radius

https://en.wikipedia.org/wiki/Gamma_ray

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Re:Why Doesn’t Gravity Happen Instantly? by jobigoud on Saturday December 19, 2020 @03:45AM (#25476136)

But spacetime can expand at a rate that makes two points recess from each other faster than the speed of light, so still weird.

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Re:Why Doesn’t Gravity Happen Instantly? by rolph on Saturday December 19, 2020 @12:36PM (#25479202)

i love to read more about this do you have any sources?

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Re:Why Doesn’t Gravity Happen Instantly? by jobigoud on Sunday December 20, 2020 @04:02PM (#25489465)

Here: http://www.mso.anu.edu.au/~charley/papers/DavisLineweaver04....

The weirdest part is that there are photons that are currently receding away from us faster than the speed of light but they will still be able to reach us eventually anyway.

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