Show that Area form is independent of parameterization?

[phyalan]

In differential geometry, how can one show that the area form: √(EG-F²)du\wedgedv is independent of the choice of local parameterization?
Here E,F,G are the coefficients of first fundamental form. Please someone gives me some ideas.

 

[Bacle2]

In differential geometry, how can one show that the area form: √(EG-F²)du\wedgedv is independent of the choice of local parameterization?
Here E,F,G are the coefficients of first fundamental form. Please someone gives me some ideas.

Maybe if you give us the definition of E, G, F and/or how they are calculated, that
would help.

And, BTW : why doesn't the independence of parametrization hold for standard
integrals in standard integration in ℝⁿ , where the area is scaled by
the determinant of the Jacobian J(f) of the change of variables?

 

[phyalan]

Actually, what I am trying to do is to change from one parameterization to another and calculate the formula by definition to see if they give the same result under different parameterization, but I am not sure I am doing something valid. For instance, E=\phi_{u}\cdot\phi_{u} where\phi is a local parameterization from a open set in R^2 to the surface concerned and \phi_{u}=\partial \phi / \partial u\circ\phi^{-1} so can I write \phi_{u}=\phi_{v}\partial v/\partial ufor another parameterization? In that case I can express the thing with determinants of Jacobian and they eventually cancel out to give same result.