Dirac delta function with contineous set of zeros

AI Thread Summary
The discussion centers on evaluating integrals involving the delta function, specifically in the context of statistical mechanics. The integral presented is ∫δ(E-p^{2}_{i}/2m)dp^{N}, where the argument of the delta function vanishes on a sphere. The user successfully changes to spherical coordinates for evaluation but seeks a general method for handling such cases with multiple arguments. A reference to the Wikipedia page on the Dirac delta function is suggested for further insights. The conversation highlights the complexity of integrating delta functions with non-linear arguments in statistical mechanics.
klabautermann
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hi!

i have a question regarding the delta function. if i have a delta distribution with an argument that is a function of multiple arguments, somthimg like:

∫δ(E-p^{2}_{i}/2m)dp^{N}, ranging over +-∞

now, the argument of the delta function vanishes on a sphere. i can evaluate the integral by changing to spherical coordinates, but in general is there a similar method to evaluate something like this as in the case of discrete zeros? my question is in the context of statistical mechanics.

thanks!
 
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klabautermann said:
hi!

i have a question regarding the delta function. if i have a delta distribution with an argument that is a function of multiple arguments, somthimg like:

∫δ(E-p^{2}_{i}/2m)dp^{N}, ranging over +-∞

now, the argument of the delta function vanishes on a sphere. i can evaluate the integral by changing to spherical coordinates, but in general is there a similar method to evaluate something like this as in the case of discrete zeros? my question is in the context of statistical mechanics.

thanks!

Check out http://en.wikipedia.org/wiki/Dirac_delta_function#Composition_with_a_function
 
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