arXiv subjects

M. Haft

Publications and source records attributed to M. Haft.

3 recordsLinked to original sources

arXiv1995

Quantum Fields a la Sylvester and Witt

A structural explanation of the coupling constants in the standard model, i.e the fine structure constant and the Weinberg angle, and of the gauge fixing contributions is given in terms of symmetries and representation theory. The coupling constants are normalizations of Lorentz invariantly embedded little groups (spin and polarization) arising in a harmonic analysis of quantum vector fields. It is shown that the harmonic analysis of massless fields requires an extension of the familiar Fourier decomposition, containing also indefinite unitary nondecomposable time representations. This is illustrated by the nonprobabilistic contributions in the electromagnetic field.

quant-ph↗

arXiv1993

Standard and Non-Standard Plasma Neutrino Emission Revisited

On the basis of Braaten and Segel's representation of the electromagnetic dispersion relations in a QED plasma we check the numerical accuracy of several published analytic approximations to the plasma neutrino emission rates. As we find none of them satisfactory we derive a new analytic approximation which is accurate to within 4\%\ where the plasma process dominates. The correct emission rates in the parameter regime relevant for the red giant branch in globular clusters are larger by about $10-20$\% than those of previous stellar evolution calculations. Therefore, the core mass of red giants at the He flash is larger by about $0.005\M_\odot$ or 1\% than previously thought. Our bounds on neutrino magnetic dipole moments remain virtually unchanged.

astro-ph↗

arXiv1992

Relativistic Mean Field Calculations of $Λ$ and $Σ$ Hypernuclei

Single--particle spectra of $Λ$ and $Σ$ hypernuclei are calculated within a relativistic mean--field theory. The hyperon couplings used are compatible with the $Λ$ binding in saturated nuclear matter, neutron-star masses and experimental data on $Λ$ levels in hypernuclei. Special attention is devoted to the spin-orbit potential for the hyperons and the influence of the $ρ$-meson field (isospin dependent interaction).

nucl-th↗