David Corfield asked the following questions yesterday: Is the
n-dimensional Fourier transform of exp(-||x||) always non-negative,
where ||.|| is the Euclidean norm on R^n?  What is its support?

I want to ask a more general question: what happens when ||.|| is the
p-norm, for arbitrary p in [1, 2]?

David's question, and Josh Shadlen's helpful answer, are here: <http://mathoverflow.net/questions/723/is-the-fourier-transform-of-exp-x-non-negative>