- #1
espen180
- 834
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I'm trying to prove that the cartesian metric [tex]g_{mn}=\delta_{mn}[/tex] doesn't change under a transformation of coordinates to another cartesian coordinate set with different orientation.
As a starting point I am using [tex]ds^2=\delta_{mn}(x)dx^m dx^n=\frac{\partial x^m}{\partial y^r}\frac{\partial x^n}{\partial y^s}\delta_{mn}(x)dy^r dy^s[/tex].
Then I have to prove that [tex]\frac{\partial x^m}{\partial y^r}\frac{\partial x^n}{\partial y^s}\delta_{mn}(x)=\delta_{rs}(y)[/tex].
However, I am unsure as to how I should tackle those coordinate derivatives. How can I show this equality?
Any help is appreciated.
As a starting point I am using [tex]ds^2=\delta_{mn}(x)dx^m dx^n=\frac{\partial x^m}{\partial y^r}\frac{\partial x^n}{\partial y^s}\delta_{mn}(x)dy^r dy^s[/tex].
Then I have to prove that [tex]\frac{\partial x^m}{\partial y^r}\frac{\partial x^n}{\partial y^s}\delta_{mn}(x)=\delta_{rs}(y)[/tex].
However, I am unsure as to how I should tackle those coordinate derivatives. How can I show this equality?
Any help is appreciated.
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