Atmospheric Neutrino Mixing and b-s Transitions: Testing Lopsided SO(10) Flavor Structure in B physics

We point out that the correlation between the large atmospheric neutrino mixing and the $b \to s$ transition, if exists, comes from the lopsided flavor structure in SO(10) grand unification theory. We suggest testing the correlation by studying the deviation of $S_{\phi K_S}$ and $S_{\eta' K_S}$ from the standard model predictions along with the constraints from $\Delta M_{B_S}$ and $b\to s \gamma$ in a realistic SO(10) model with lopsided flavor structure. We find a specific correlation between $S_{\phi K_S}$ and $S_{\eta' K_S}$ that is intrinsic to the lopsided structure and discuss how to confirm or rule out this flavor pattern by the more accurate measurements of these CP violation quantities in B decay.