Is the Schwarzschild metric dimensionless?

help1please
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Homework Statement



The problem is I am wanting to know if the expression on the right hand side is dimensionless.

Homework Equations



ds^2 = (1 - \frac{2GM}{c^2 r})c^2 dt^2

The Attempt at a Solution



Since the Schwarzschild radius is r = \frac{2GM}{c^2} would I be right in saying that

\frac{2GM}{c^2 r}

is dimensionless?
 
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help1please said:

The Attempt at a Solution



Since the Schwarzschild radius is r = \frac{2GM}{c^2} would I be right in saying that

\frac{2GM}{c^2 r}

is dimensionless?

Yes, it is.
 
Note that it would have to be if the formula is valid since you're subtracting that quantity from 1, which is dimensionless.
 
Of course it is. Note that sometime we write metric in this form:1-\frac{2GM}{r}
just a matter of unit conventions.
 
thanks every1
 
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