Electromagnetism with Magnetic Charge and Two Photons

The Dirac approach to include magnetic charge in Maxwell's equations places the magnetic charge at the end of a string on which the the fields of the theory develop a singularity. In this paper an alternative formulation of classical electromagnetism with magnetic and electric charge is given by introducing a second pseudo four-vector potential, C_mu, in addition to the usual four- vector potential, A_mu. This avoids the use of singular, non-local variables (i.e. Dirac strings) in electrodynamics with magnetic charge, and it makes the treatment of electric and magentic charge more symmetric, since both charges are now gauge charges.Comment: 20 page, 0 figures. Published in AJP. Proposes the possiblity of an additional U(1) magnetic, gauge boso

Gravitons to Photons -- attenuation of gravitational waves

In this essay we examine the response of an Unruh-DeWitt detector (a quantum two-level system) to a gravitational wave background. The spectrum of the Unruh-Dewitt detector is of the same form as some scattering processes or three body decays such as muon-electron scattering or muon decay. Based on this similarity we propose that the Unruh-DeWitt detector response implies a "decay" or attenuation of gravitons, $G$, into photons, $\gamma$, via $G + G \rightarrow \gamma + \gamma$ or $G \rightarrow \gamma + \gamma + G$. Over large distances such a decay/attenuation may have consequences in regard to the detection of gravitational waves.Comment: 8 pages, 0 figures. "Honorable mention" in the 2015 Gravity Research Foundation Essay Contest. Acknowledgment added. Published versio