How to Fourier transform this expression?

AI Thread Summary
The discussion centers on the expression f(τ) = 4π ∫ ω² P₂[cos(ωτ)] P(ω) dω, where P₂ is a Legendre polynomial and P(ω) is a distribution function. The user seeks to solve for P(ω) from a dataset of f(τ) by either assuming a model or applying a Fourier transform to the equation. They express confusion about directly obtaining P(ω) through Fourier transformation and inquire about methods to implement this in MATLAB or Mathematica. The conversation highlights the need for clarity on the Fourier transform process in this context. Additional information or examples may be required for better guidance.
Steve Drake
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I have this expression:
f(\tau) = 4 \pi \int \omega ^2 P_2[\cos (\omega \tau)] P(\omega) \, \mathrm{d}w \quad [1] where P_2 is a second order Legendre polynomial, and P(\omega) is some distribution function.

Now I am told that, given a data set of f(\tau), I can solve for P(\omega) by either assuming a model for it or Fourier transforming Eq. [1]. I can do this by assuming a distribution, eg Gaussian, then putting it in the integral, but I do not understand how I can obtain P(\omega) directly via Fourier transforming. How could I do this in say MATLAB or Mathematica?

Thanks
 
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