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This question involves the following statement in Schutz, A First Course in GR, but you don't need to have a copy to answer it.

He says that in the formation of a black hole from a supernova explosion, we should expect gravity waves of amplitude M/R, where M is the mass and R is the distance to the explosion. He goes on to say that for a black hole of 10 solar masses, whose distance is [itex]10^{23}m[/itex], this is about [itex]10^{-17}[/itex]. Since 1 solar mass is roughly [itex]10^3m[/itex], M/R for the black hole itself would be [itex]10^{-19}[/itex]. This seems to imply that it would take the supernova explosion of a star of 1000 solar masses to create a black hole of 10 solar masses. Is this correct?

He says that in the formation of a black hole from a supernova explosion, we should expect gravity waves of amplitude M/R, where M is the mass and R is the distance to the explosion. He goes on to say that for a black hole of 10 solar masses, whose distance is [itex]10^{23}m[/itex], this is about [itex]10^{-17}[/itex]. Since 1 solar mass is roughly [itex]10^3m[/itex], M/R for the black hole itself would be [itex]10^{-19}[/itex]. This seems to imply that it would take the supernova explosion of a star of 1000 solar masses to create a black hole of 10 solar masses. Is this correct?

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