B How Can We Detect Gravitational Waves from Black Holes?

negative
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well since gravity waves are supposed to have mass, they are supposed to be effected by gravity itself, and :/ how are we supposed to detect gravitational waves emitted from a black hole when none can get out?
 
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negative said:
gravity waves are supposed to have mass

No, they don't. They carry energy, but they have zero stress-energy.

negative said:
they are supposed to be effected by gravity itself

In the sense that they follow the geometry of spacetime, yes.

negative said:
how are we supposed to detect gravitational waves emitted from a black hole when none can get out?

The gravitational waves detected by LIGO were not emitted from inside black holes. They were emitted from outside the horizons of merging black holes.
 
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PeterDonis said:
No, they don't. They carry energy, but they have zero stress-energy.
In the sense that they follow the geometry of spacetime, yes.
The gravitational waves detected by LIGO were not emitted from inside black holes. They were emitted from outside the horizons of merging black holes.
thank's that clears thing up. but , don't gravity waves move slower than the speed of light? 0_o still no mass?
 
negative said:
don't gravity waves move slower than the speed of light?

No. They are massless and move at the speed of light.
 
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