Fourier transform of a differential equation

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AxiomOfChoice
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Homework Statement


I'm supposed to take the "spatial Fourier transform" of the partial differential equation

[tex] p_t = \frac{a^2}{2\tau}p_{xx} + 2g(p + xp_x)[/tex]

for [itex]p = p(x,t)[/itex].

Homework Equations


Well, I guess I eventually need something like

[tex] \phi(k,t) = \mathbb F(p(x,t)) = \frac{1}{\sqrt{2\pi}} \int_{-\infty}^{\infty} p(x,t) e^{-ikx}\ dx.[/tex]

The Attempt at a Solution


I've never done anything like this before, so I'm really not sure what to do. I think if I get a few hints or a gentle nudge in the right direction, I'll be good to go, though.

I'm guessing that I should take the spatial Fourier transform [itex]\mathbb F[/itex] of both sides. So the LHS would become

[tex] \mathbb F(p_t) = \frac{1}{\sqrt{2 \pi}} \int \frac{\partial p}{\partial t}e^{-ikx}dx = \frac{1}{\sqrt{2 \pi}} \frac{\partial}{\partial t} \int p(x,t) e^{-ikx}dx = \phi_t.[/tex]

Is this right?
 
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And then I guess we can use the rule that

[tex] \mathbb F(p_{xx}) = -k^2 \mathbb F(p)[/tex]

to conclude that the transform of the first term on the RHS is just

[tex] -\frac{a^2k^2}{2\tau} \phi.[/tex]

So, at the end of the day, our differential equation becomes

[tex] \phi_t = -\frac{a^2k^2}{2\tau} \phi + 2g(\phi + \mathbb F(xp_x)).[/tex]

That last term on the right is giving me fits!