Fourier Transforms: Proving Proportionality

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The discussion focuses on using Fourier transforms to demonstrate the proportionality of a specific wave packet to a Gaussian function. The initial attempt involved a Fourier transform of the form e^(ikx), which did not yield the expected result. After resolving the integral for the wave packet, the next challenge was to solve a more complex integral involving additional parameters. The user successfully solved this integral but expressed uncertainty about how to graph the resulting function. The conversation highlights the application of Fourier transforms in wave packet analysis and the challenges in visualizing the results.
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1. We consider the on shell wave packet:
\varphi(t,x)=\int\frac{dk}{2\pi}exp(-\frac{(k-k_{0})^{2}}{\Delta k^{2}}+ik(t-x))dk<br />

I need to show it is proportional to:
exp(ik_{0}(t-x)-\frac{\triangle k^{2}}{4}(t-x)^{2})dk
through a Fourier transform of the gaussian


3. I used a Fourier transform of the form e^(ikx) but this doesn't seem to give me the right answer as I end up with something proportional to exp(-\frac{(k-k_{0})^{2}}{\triangle k^{2}}+ikt)dk before integrating
 
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Show us what you think the integral for ##\varphi(t,k)## is.
 
Solved it! :-)...

However I now need to solve this:

\int\frac{dk}{2\pi}exp(-\frac{(k-k_{o})^{2}}{\triangle k^{2}}+ik(pt-x)


where p=1-\frac{h_{00}}{2}-h_{01}-\frac{h_{11}}{2}

by using Fourier transforms
 
Solved this one too now :-)

Not sure how to graph it though...
 
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