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T. Goldman

Publications and source records attributed to T. Goldman.

116 records · Page 7Linked to original sources
arXiv1993

(J,0)+(0,j) Representation Space: Majorana-Like Construct

This is second of the two invited lectures presented (by D. V. Ahluwalia) at the ``XVII International School of Theoretical Physics: Standard Model and Beyond' 93.'' The text is essentially based on a recent publication by the present authors [Mod. Phys. Lett. A (in press)]. Here, after briefly reviewing the $(j,0)\oplus(0,j)$ Dirac-like construct in the front form, we present a detailed construction of the $(j,0)\oplus(0,j)$ Majorana-like fields.

hep-th↗
arXiv1993

Observable Consequences of a Scalar Boson Coupled only to Neutrinos

We have examined the consequences of assuming the existence of a light scalar boson, weakly coupled to neutrinos, and not coupled to any other light fermions. For a range of parameters, we find that this hypothesis leads to the development of neutrino clusters which form in the early Universe and which provide gravitational fluctuations on scales small compared to a parsec (i.e., the scale of solar systems). The existence of such clustering produces an effect which would appear as a negative mass squared for the electron neutrino in Tritium beta decay, without conflicting with other experiments. The neutrino masses arising in unified gauge theories would then be very much larger than the masses extracted from experiments within the solar system.

hep-ph↗
arXiv1993

A Bargmann-Wightman-Wigner Type Quantum Field Theory

This version corrects an inportant typographical error in Eq. 17. COMMENTS, FOR THE RECORD: A referees reoprt from Phys. Rev. Lett. read in part ``The first named author has appreciated my exceptionally long report. He has read and well assimilated the literature I suggested. Congratulations! This very new version of the manuscript has now three authors and carries a very well chosen title. Indeed Bargmann, Wightman and Wigner had studied, this subject forty years ago, in an unpublished book (several chapters were distributed as preprints). The authors explain well the scope of their paper. They have made a thorough construction of a field theory of a non usual Wigner type; that is completely new and all references are relevant. {\it This paper should be published.}" Despite the fact that no other report was received, the editors of Phys. Rev. Lett. rejected this paper. D.V.A.

hep-ph↗
arXiv1993

No-Lose `Theorem' for Parity Violating Nucleon-Nucleon Scattering Experiments

A purely left-chiral model of the weak interactions is used to show that the total parity-violating asymmetry in quark-quark scattering must grow with increasing energy. In the absence of other new physics, non-observation of a large asymmetry can therefore be used to infer an upper bound on the mass scale for new right-chiral weak vector bosons. Applying this idea to actual nucleon-nucleon scattering requires more involved calculations, as the dominant contribution appears to come from a component of diquark-quark scattering related to, but not identical to, wavefunction-mixing. Earlier criticism of this model by Simonius and Unger is refuted and a new calculation is proposed as an additional check on the result. Finally, we argue that the so-called `spin crisis' does not affect our conclusions. (Talk given at the BNL workshop on future directions in particle and nuclear physics at multi-GeV hadron beam facilities, March 4--6, 1993.)

nucl-th↗
arXiv1993

Color Magnetic Corrections to Quark Model Valence Distributions

We calculate order $α_s$ color magnetic corrections to the valence quark distributions of the proton using the Los Alamos Model Potential wavefunctions. The spin-spin interaction breaks the model SU(4) symmetry, providing a natural mechanism for the difference between the up and down distributions. For a value of $α_s$ sufficient to produce the $N-Δ$ mass splitting, we find up and down quark distributions in reasonable agreement with experiment.

nucl-th↗
arXiv1992

The Dark Matter Problem in Light of Quantum Gravity

We show how, by considering the cumulative effect of tiny quantum gravitational fluctuations over very large distances, it may be possible to: ($a$) reconcile nucleosynthesis bounds on the density parameter of the Universe with the predictions of inflationary cosmology, and ($b$) reproduce the inferred variation of the density parameter with distance. Our calculation can be interpreted as a computation of the contribution of quantum gravitational degrees of freedom to the (local) energy density of the Universe.

gr-qc↗
arXiv1992

Modelling the Off-Shell Dependence of $π^{o}- η$ Mixing with Quark Loops

It is shown that including form factors for the quark-pseudoscalar meson couplings of the Georgi-Manohar chiral quark model allows one to obtain the leading off-shell dependence of $π^{o}- η$ mixing (as predicted by chiral perturbation theory) from the effect of quark loops on the meson propagators. Implications for $ρ^{o} - ω$ mixing and for the effects on meson mixing contributions to few body charge symmetry breaking observables are also discussed.

nucl-th↗