How do I prove that the coordinate independant definitions of the Hodge dual operator are equivalent?

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I am trying to show that the different ways of defining the Hodge star operator are equivalent.

I started with the following definition from the following lecture notes "An application of discrete differential geometry to the spectral element method" by G. Oud.

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Then one can show that

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Where the index sets H and K are defined as $H:=\{1,...,p\}$ and $K:=\{p+1,...,n\}$. I am fine with that. Then it says that from that one can derive the formula:

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My Questions:

  • Can equation 1.35 be shown by using linearity and the fact that $\star e^{H}=g(e^{K},e^{K})e^{K}$?
  • How is the other direction shown, i.e, equation 1.35 implies equation 1.31? My guess is that I need to use $\star\star$, but then I only get the answer up to $(-1)^{k(n-k)}$.
  • Is there a way to show equation 1.35 implies equation 1.31 without using $\star\star$?

Thank you very much in advance for your help!