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\title{Free Particles and Pi}
\author{Ryan Dickherber}
\date{Dec. 19, 2007}
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Years ago I had a conversation with my then-girlfriend; a non-mathematician.
I was explaining to her the Gaussian distribution, and how it is useful in determining the probable location of a free particle shortly after wavefunction collapse.

``I see that the Gaussian distribution depends upon pi,'' she said.
``How can it be that the probable location of a particle depends so crucially upon the ratio of the circumference of a circle to its diameter?''

I had to laugh.

``You have it backwards,'' I said.
``It's the ratio of the circumference of a circle to its diameter that depends crucially upon the probable location of a free particle.''

I continued laughing for several minutes.

This is how she became known as the ``ex.''
One of the exes, anyway.
I have similar stories for the others.
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