Super-light baryo-photons, weak gravity conjecture and exotic instantons in neutron-antineutron transitions
【摘要】：In companion papers(A. Addazi, Nuovo Cim. C, 38(1): 21(2015); A. Addazi, Z. Berezhiani, and Y. Kamyshkov, ar Xiv:1607.00348), we have discussed current bounds on a new super-light baryo-photon, associated with a U(1)B-L gauge, from current neutron-antineutron data, which are competitive with E¨otv¨os-type experiments.Here, we discuss the implications of possible baryo-photon detection in string theory and quantum gravity. The discovery of a very light gauge boson should imply violation of the weak gravity conjecture, carrying deep consequences for our understanding of holography, quantum gravity and black holes. We also show how the detection of a baryophoton would exclude the generation of all B-L violating operators from exotic stringy instantons. We will argue against the common statement in the literature that neutron-antineutron data may indirectly test at least the 300-1000 Te V scale. Searches for baryo-photons can provide indirect information on the Planck(or string) scale(quantum black holes, holography and non-perturbative stringy effects). This strongly motivates new neutron-antineutron experiments with adjustable magnetic fields dedicated to the detection of super-light baryo-photons.