In Lorentz-violating electrodynamics a steady current (and similarly a static charge) generates both static magnetic and electric fields. These induced fields, acting on interfering particles, change the interference pattern. We find that particle interference experiments are sensitive to small Lorentz violating effects, and thus they can be used to improve… (More)
The modifications induced in the standard weak-lensing formula if Newtonian gravity differs from inverse square law at large distances are studied. The possibility of putting bounds on the mass of gravitons from lensing data is explored. A bound on graviton mass, esitmated to be about 100 Mpc −1 is obtained from analysis of some recent data on gravitational… (More)
The electric and magnetic dipole moments of the rho meson are calculated using the propagators and vertices derived from the QCD Dyson-Schwinger equations. Results obtained from using the Bethe-Salpeter amplitude studied by Chappell, Mitchell and Tandy, and Pichowsky and Lee, are compared. The rho meson EDM is generated through the inclusion of a quark… (More)
We review how antiparticles may be introduced in classical relativistic mechanics, and emphasize that many of their paradoxical properties can be more transparently understood in the classical than in the quantum domain.
We consider the possibility that neutrinos are coupled very weakly to an extremely light scalar boson. We first analyze the simple problem of one generation of neutrino and show that, for ranges of parameters that are allowed by existing data, such a system can have serious consequences for the evolution of stars and could impact precision laboratory… (More)
We study the effects of a scalar field, coupled only to neutrinos, on oscillations among weak interaction current eigenstates. The effect of a real scalar field appears as effective masses for the neutrino mass eigenstates, the same for ¯ ν as for ν. Under some conditions, this can lead to a vanishing of δm 2 , giving rise to MSW-like effects. We discuss… (More)
In a recent paper, oscillations observed in the electron capture probability were attributed to the mixing of neutrino mass eigenstates. This paper is shown to be in error in two respects. In a recent measurement at GSI of the electron capture rate for hydrogen-like 140 P r ions, 140 P r 58+ → 140 Ce 58+ + ν (1) the decaying ions were found to have a… (More)
We argue that magnetic and electric charges of the Reissner-Nordstrom black hole are quantized in CP conserving theories. Dequantization phenomenon occurs when CP is broken either explicitly or effectively, and, as a result, pure magnetic black holes are not possible. Two examples illustrating this phenomenon are discussed. One is the electric charge… (More)
While it has long been known that many models of high energy scattering give cross sections which rise as ln 2 s, the determination of the coefficient of this term is rarely given. We show that in gaussian and exponential eikonal models an exact expression for the cross section can be obtained, which demonstrates the ln 2 s asyptoptic behaviour and… (More)
We calculate the masses of the lowest lying eigenstates of improved SU(2) and SU(3) lattice gauge theory in 2+1 dimensions using an analytic variational approach. The ground state is approximated by a one plaquette trial state and mass gaps are calculated in the symmetric and antisymmetric sectors by minimising over a suitable basis of rectangular states.