Sidharth, Burra G.

In the theory of the Dirac equation and in the standard model, the neutrino is massless. Both these theories use Lorentz invariance. In modern approaches however, spacetime is no longer smooth, and this modifies special relativity. We show how such a modification throws up the mass of the (electron) neutrino.

Kimura, Masashi Murata, Keiju Ishihara, Hideki Soda, Jiro

The stability of squashed Kaluza-Klein black holes is studied. The squashed Kaluza-Klein black hole looks like five dimensional black hole in the vicinity of horizon and four dimensional Minkowski spacetime with a circle at infinity. In this sense, squashed Kaluza-Klein black holes can be regarded as black holes in the Kaluza-Klein spacetimes. Usin...

Wetterich, Christof

We derive a new exact evolution equation for the scale dependence of an effective action. The corresponding equation for the effective potential permits a useful truncation. This allows one to deal with the infrared problems of theories with massless modes in less than four dimensions which are relevant for the high temperature phase transition in ...

Birkandan, T.

We present a Maple11+GRTensorII based symbolic calculator for instanton metrics using Newman-Penrose formalism. Gravitational instantons are exact solutions of Einstein's vacuum field equations with Euclidean signature. The Newman-Penrose formalism, which supplies a toolbox for studying the exact solutions of Einstein's field equations, was adopted...

Kichenassamy, Satyanad Rendall, Alan D.

We use Fuchsian Reduction to construct singular solutions of Einstein's equations which belong to the class of Gowdy spacetimes. The solutions have the maximum number of arbitrary functions. Special cases correspond to polarized, or other known solutions. The method provides precise asymptotics at the singularity, which is Kasner-like. All of these...

Kostyuk, Andriy Korol, Andrei Solov'yov, Andrey Greiner, Walter

A new Monte Carlo code for the simulation of the channeling of ultrarelativistic charged projectiles in single crystals is presented. A detailed description of the underlying physical model and the computation algorithm is given. First results obtained with the code for the channeling of 855 MeV electrons in Silicon crystal are presented. The decha...

Kichenassamy, Satyanad

This paper presents an asymptotic reduction of the Einstein-Klein-Gordon system with real scalar field ("soliton star problem"). A periodic solution of the reduced system, similar to the sine-Gordon breather, is obtained by a variational method. This tallies with numerical computations. As a consequence, a time-periodic redshift for sources close t...

Owen, James E. Ercolano, Barbara Clarke, Cathie J.

(Abridged) We explore the role of X-ray photoevaporation in the evolution and dispersal of viscously evolving T-Tauri discs. We show that the X-ray photoevaporation wind rates scale linearly with X-ray luminosity, such that the observed range of X-ray luminosities for solar-type T-Tauri stars (10e28-10e31 erg\s) gives rise to vigorous disc winds wi...

Olness, Fredrick Scalise, Randall

We illustrate the dimensional regularization technique using a simple problem from elementary electrostatics. We contrast this approach with the cutoff regularization approach, and demonstrate that dimensional regularization preserves the translational symmetry. We then introduce a Minimal Subtraction (MS) and a Modified Minimal Subtraction (MS-Bar...

Barci, D. G. Bollini, C. G. Rocca, M. C.

Following the canonical quantization procedure for a tachyon field, the usual Hamiltonian and the creation and annihilation operators are obtained. The observation that the mass hyperboloid $p^2-m^2=0$ is one-sheeted, as opposed to the case of bradyons where $p^2+m^2=0$ is two-sheeted, leads to the construction of a base which is unbounded for nega...