## Sunday, May 16, 2010

### M Theory Lesson 327

Thanks to Carl Brannen, I took a look at this 2005 paper by Bjorken, Harrison and Scott. In this paper, the tribimaximal mixing matrix is extended by a one parameter factor not unlike that of the third $R_2$ factor in $M$. Moreover, their parameter is also closely related to a near zero mixing matrix entry.

As pointed out in the paper, unitarity triangles now take a simpler form. We saw that the $M$ phases, for $(a,b,c)$ $=$ $(-0.231, 24, 0.0035)$, give a value of $0.04$ for the $2 \beta_s$ parameter. This angle comes mostly from the $(ts)$ term, since the other three angles in $2 \beta_s$ roughly cancel out.