## Saturday, October 22, 2011

### Dark Matter at the LHC

If there are any remaining scientists who think blogging has no role to play in science, you had better hold on to your hats. Derek Teaney made a comment just now on Woit's blog:
In particular, the remarkable aspect of the new data is the success of hydrodynamics in describing the new data on the higher harmonics flow when the shear
viscosity is of order $1 - 3/ 4\pi$.
That's the shear viscosity to entropy ratio of the quark gluon plasma at RHIC or the LHC. Observe that $3/ 4 \pi$ is also precisely Riofrio's dark matter fraction $\Omega_{d}$, derived entirely without string theory. Yes, seriously. Quarks are, after all, complementary to leptons, including the neutrinos, whose rest mass quantum numbers can determine the CMB temperature.

1. Note that Teaney refers to the range $1$ to $3$. That's not a minus sign. The minimal value $1/ 4 \pi$ is the $N=4$ SYM value.

2. Have you ever considered that the CMB temperature might determine the mass scale?

This is a very striking connection you've made with Louise's number. I gather that 1/4π is the viscosity for the deconfined phase of any strongly coupled gauge theory with a gravitational dual. QCD is strongly coupled, but SU(2) also becomes confining at strong coupling, so I even wonder if you could view the cosmic neutrino background as the "deconfined plasma". In fact, if you think in terms of Seiberg duality, there can be a relation between 3 colors and 3 generations, and the weak SU(2) can be emergent from the strong SU(3), so the factor of 3 might come from some shared underlying 3-ness... And I suppose one should try to understand Louise's singularities as the holographic source of the viscosity. Remarkable!

3. Have you ever considered that the CMB temperature might determine the mass scale?

Good question, and yes, that is a basic point of the new cosmology. As you know, gravity has thermodynamic characteristics, and Louise's rule may be interpreted as a relation between mass and CMB temperature, since the temperature defines a cosmic time. Your comments on the number $3$ have long been a motivation for this approach.

But I am still somewhat confused about how this fits in with the Koide triplets. It would be nice if more people were working on this.

4. Thanks again for your supportive posts. The prediction, from 2004, of 4.507034% baryons is too close to remain hidden forever.

5. A confirmed prediction at that, Louise!