Considering the definition of inertial forces acting on a test particle, following non-circular geodesics, in static and stationary space times we show that the centrifugal force reversal occurs only in the case of particles following prograde orbits around black holes. We first rewrite the covariant expressions for the acceleration components in terms of the lapse function , shift vector and t...

In this paper QED in 2+1 dimensions is studied. We offer a simple physical description of the mechanism that gives rise to anomalous fermion currents and the “topological” mass (Chern-Simmons term) in the effective gauge theory. The dynamical properties of the fermions are analyzed and explained in some detail. The physical properties responsible for these anomalous effects are identified and t...

This paper aims to present explicit photon-like (3+1) spatially finite soliton solutions of screw type to the vacuum field equations of Extended Electrodynamics (EED) in relativistic formulation. We begin with emphasizing the need for spatially finite soliton modelling of microobjects. Then we briefly comment the properties of solitons and photons and recall some facts from EED. Making use of t...

a. Corresponding author b. Haas School of Business, University of California at Berkeley, 545 Student Services #1900, Berkeley, CA 94720, USA. [email protected], +1 (510) 643-4272 c. NUS Business School, National University of Singapore, BIZ 1, 8-26, 15 Kent Ridge Drive, Singapore 119245. d. Haas School of Business, University of California at Berkeley, 545 Student Services #1900, Berkeley, C...

We have discovered theoretically that ionization of a one-dimensional quantum well by an ultrashort subcycle ~d-like! electromagnetic pulse results in photoelectrons propagating both along the field and in the opposite direction in well-separated shells whose velocities reflect quasiresonances in the ionization continuum. For both a quantum well and a three-dimensional hydrogenlike atom, a unip...

After briefly reviewing the hamiltonian approach to 2+1 dimensional gravity in absence of matter on closed universes, we consider 2+1 dimensional gravity coupled to point particles in an open universe. We show that the hamiltonian structure of the theory is the result of a conjecture put forward by Polyakov in a different context. A proof is given of such a conjecture. Finally we give the exact...

We consider solutions to the wave equation in 3+1 spacetime dimensions whose data is compactly supported at some initial time. For points outside a ball containing the initial support, we develop an outgoing wave condition, and associated one-way propagation formula, for the partial waves in the spherical-harmonic decomposition of the solution. The propagation formula expresses the l-th partial...

By using the spherical coordinates in 3+1 dimensions we study the self-adjointness of the Dirac Hamiltonian in an Aharonov-Bohm gauge field of an infinitely thin magnetic flux tube. It is shown that the angular part of the Dirac Hamiltonian requires self-adjoint extensions as well as its radial one. The self-adjoint extensions of the angular part are parametrized by a 2 × 2 unitary matrix. ∗e-m...

We construct an exact solution describing the collision of two Kaluza-Klein “bubbles of nothing” in 3+1 dimensions. When the bubbles collide, a curvature singularity forms which is hidden inside an event horizon. However, unlike the formation of ordinary black holes, in this case the spacetime resembles the entire maximally extended Schwarzschild solution. We also point out that there are inequ...

We consider a hydrogenic system with a nucleus of finite mass. The coupling of the radiation field to the center of mass motion gives rise to an effective scalar type coupling. This induced scalar photon interaction emerges as a correction in competition with the usual multipole interactions. This effect is particularly important in positronium where the electric quadrupole interaction is total...