Phenomenology with String Lanscape

 Some people have the view that string theory has no de Sitter vacua, let alone an astronomical number. I have been posting on this issue. I intend to do that further. In the meantime there are papers that are going ahead with string theory phenomenology. The paper with the following abstract also does that.

String Landscape and Fermion Masses

Stefano Andriolo, Shing Yan Li, S.-H. Henry Tye

Besides the string scale, string theory has no parameter except some quantized flux values; and the string theory Landscape is generated by scanning over discrete values of all the flux parameters present. We propose that a typical (normalized) probability distribution P(Q) of a physical quantity Q (with nonnegative dimension) tends to peak (diverge) at Q=0 as a signature of string theory. In the Racetrack Kähler uplift model, where P(Λ) of the cosmological constant Λ peaks sharply at Λ=0, the electroweak scale (not the electroweak model) naturally emerges when the median Λ is matched to the observed value. We check the robustness of this scenario. In a bottom-up approach, we find that the observed quark and charged lepton masses are consistent with the same probabilistic philosophy, with distribution P(m) that diverges at m=0, with the same (or almost the same) degree of divergence. This suggests that the Standard Model has an underlying string theory description, and yields relations among the fermion masses, albeit in a probabilistic approach (very different from the usual sense). Along this line of reasoning, the normal hierarchy of neutrino masses is clearly preferred over the inverted hierarchy, and the sum of the neutrino masses is predicted to be ∑mν≃0.0592 eV, with an upper bound ∑mν<0.066 eV. This illustrates a novel way string theory can be applied to particle physics phenomenology.