Breaking up the Proton: An Affair with Dark Forces.

Deep inelastic scattering of e^{±} off protons is sensitive to contributions from "dark photon" exchange. Using HERA data fit to HERA's parton distribution functions (PDFs), we obtain the model-independent bound ε≲0.02 on the kinetic mixing between hypercharge and the dark photon for dark photon masses ≲10  GeV.

Gravitational baryogenesis.

We show that a gravitational interaction between the derivative of the Ricci scalar curvature and the baryon-number current dynamically breaks CPT in an expanding Universe and, combined with baryon-number-violating interactions, can drive the Universe towards an equilibrium baryon asymmetry that is observationally acceptable.

Black hole evaporation with separated fermions.

In models with a low quantum gravity scale, fast proton decay can be avoided by localizing quarks and leptons to separated positions in an extra 1/TeV sized dimension with gauge and Higgs fields living throughout. Black holes with masses of the order of the quantum gravity scale are therefore expected to evaporate nonuniversally, preferentially radiating directly into quarks or leptons but not both. Should black holes be copiously produced at a future hadron collider, we find the ratio of final state jets to charged leptons to photons is 113:8:1, which differs from previous analyses that assumed all standard model fields live at the same point in the extra dimensional space.