Fourier Transform of Integro-Differential Equation

Click For Summary

Homework Help Overview

The discussion revolves around finding the Fourier Transform of a specific integro-differential equation involving a function of time, denoted as \(\hat{{\cal E}}(t)\). The equation includes terms related to integrals and parameters such as \(\kappa\), \(g\), and \(\gamma\).

Discussion Character

  • Exploratory, Conceptual clarification

Approaches and Questions Raised

  • The original poster attempts to apply the Fourier Transform to the integro-differential equation and seeks validation of their approach. Some participants question the clarity of the equation and whether any components may be missing.

Discussion Status

The discussion is ongoing, with participants providing feedback on the original poster's attempt. While one participant expresses that the equation looks acceptable, they also suggest that something might be missing, indicating a lack of consensus on the completeness of the solution.

Contextual Notes

There is a suggestion that the complexity of the equation may be intimidating, and the original poster is encouraged to clarify their statements or assumptions further.

Nusc
Messages
752
Reaction score
2

Homework Statement


I need to find the Fourier Transform of this integro-differential equation:

<br /> \begin{subequations}<br /> \begin{eqnarray}<br /> \nonumber<br /> \dot{\hat{{\cal E}}}(t) &amp;=&amp; -\kappa \hat{{\cal E}}(t) + i g\int_{-\infty}^{\infty} d \Delta\; \hat{{\cal \rho}}(\Delta)\,( \hat{\sigma}_{ge,0}(t_{0},\Delta)e^{-(\gamma +i\Delta)(t-t_{0})} <br /> \nonumber\\<br /> &amp; &amp; + e^{-(\gamma + i\Delta)(t-t_{0})} ig\int_{t_{0}}^{t} d t&#039; \hat{{\cal E}}(t&#039;)e^{(\gamma +i\Delta)(t-t&#039;)})<br /> \nonumber\\<br /> &amp; &amp; + \sqrt{2\kappa}\, \hat{{\cal E}}_{in}, \\<br /> \nonumber<br /> \end{eqnarray}<br /> \end{subequations}<br /> <br />

Homework Equations


<br /> \hat{{\cal E}}}(t) <br />
is just a function of t

The Attempt at a Solution


<br /> After applying the Fourier Transform,<br /> \begin{subequations}<br /> \begin{eqnarray}<br /> \omega \; \tilde{\hat{{\cal E}}}(\omega) &amp;=&amp; -\frac{\kappa}{\sqrt{2\pi}} \int_{-\infty}^{\infty} \hat{{\cal E}}(t)e^{-i\omega t} dt + ig\int_{-\infty}^{\infty} d \Delta\; \hat{{\cal \rho}}(\Delta)\, \hat{\sigma}_{ge,0}(t_{0},\Delta)e^{-(\gamma +i\Delta)(t-t_{0})}<br /> \nonumber\\<br /> &amp; &amp; - g^{2}e^{-(\gamma +i\Delta)(t-t_{0})}\int_{-\infty}^{\infty} d \Delta\; \hat{{\cal \rho}}(\Delta)\,\int_{t_{0}}^{t} d t&#039; \hat{{\cal E}}(t&#039;)e^{(\gamma +i\Delta)(t-t&#039;)}<br /> + \sqrt{2\kappa}\, \frac{1}{\sqrt{2\pi}} \int_{-\infty}^{\infty} \hat{{\cal E}}_{in}(t)e^{-i\omega t} dt, \nonumber\\ \nonumber<br /> \end{eqnarray}<br /> \end{subequations}<br /> <br />

is this correct?
 
Last edited:
Physics news on Phys.org
Is this equation too intimidating?
 
Any thoughts? Did I not make myself clear?
 
Honestly it looks ok, but something looks like it may be missing. I don't have much experience with it, but it does seem ok.
 

Similar threads

Replies
1
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 6 ·
Replies
6
Views
4K
  • · Replies 31 ·
2
Replies
31
Views
5K
Replies
6
Views
3K