Curved trails by motion of heavenly bodies in space

dpa
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Hi all,

This is a kind of idiotic question.

The presence of heavenly bodies in cosmos creates curvature in cosmos according to GR and the space has a kind of fluid like nature. I was wondering if the motion of stars through space creates trails. It sure doesnot. My question is why not?
 
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That is an excellent question :-) Actually it does, but the waves produced are very very very tiny. They are so tiny, measuring the waves generated like this is impossible, even in theory. There are some experiments going on trying to measure gravitational waves generated by black hole binary systems, which are shedding a large part of their kinetic energy to gravitational radiation. Even this is very challenging.
 
ooh, i don't know :confused:

that's waves, which spread out, and the question was about localised trails, as from an aircraft or in a cloud chamber

so the question is whether there's anything that could "condense" :wink:
 
Oh I see, well then no. Because perturbations like that travel always at the speed of light. You would need a source constantly sending a signal to get a static perturbation.

I was thinking like a wake left by a boat. It works for multiple bodies, but a single test particle in a vacuum does not leave a wake, because space is not viscous. You don't lose energy to the medium and therefore there are no waves.
 
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