# Daily Archives: July 24, 2008

## Pop quiz! Spin Powers, and latest MNS news

I’ve been working on a derivation of the tribimaximal MNS matrix from first principles. It looks like it will require an assumption that the underlying particles follow a set of mutually unbiased bases (MUB). The calculation involves spin products. These are messy to compute unless you know some tricks I’ve discussed here previously.

So, did I waste my breath? Is teaching how to compute these things like shouting down a well? Let’s have a contest. First person to solve the following problem gets a \$50 prize:

“Solve” means to write the above in reduced closed form in the comments section. The solution must be exact, for example, it must use $\pi$ rather than some numeric approximation such as 3.14159. Now I’ve chosen the values so that it will be easy to do with the techniques shown here, but will cause problems with mathematica or other automatic assistants. So go for the glory! Of course the winner can also ask that the prize be donated to a needy physicist such as Marni Sheppeard.

Meanwhile, I’ll share a few lines on what I’m doing with spin sums and the MNS matrix. Continue reading