- #1

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## Main Question or Discussion Point

How do you obtain this equation M=Gm/c^2. What does M stand for? Is is newton law at infinity? Again what is this newton law at infinity?

- Thread starter TimeRip496
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- #1

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How do you obtain this equation M=Gm/c^2. What does M stand for? Is is newton law at infinity? Again what is this newton law at infinity?

- #2

Nugatory

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M is just the mass of the black hole using units in which G and c are both equal to one.How do you obtain this equation M=Gm/c^2. What does M stand for?

We don't have to make this substitution but if we don't we'll be schlepping factors of G and c around everywhere in our equations, and they're complicated enough already.

- #3

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Do you mind telling me a source for such derivation? Cause all the Internet gives is just the derivation of the schwarzschild radius.M is just the mass of the black hole using units in which G and c are both equal to one.

We don't have to make this substitution but if we don't we'll be schlepping factors of G and c around everywhere in our equations, and they're complicated enough already.

- #4

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It's just a conversion factor from mass units to length units; ##Gm / c^2## converts the mass ##m## to an equivalent length. The Schwarzschild radius corresponding to ##m## is just twice that equivalent length.Do you mind telling me a source for such derivation?

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