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Richard T Hammond

Publications and source records attributed to Richard T Hammond.

10 recordsLinked to original sources
arXiv2020

Gravitational dipole moment from an exact solution with torsion

Dipole fields are common in electromagnetism and may be viewed as the result of a positive and negative charge (or pole) which are close together. A dipole field in gravity is not expected to exist because negative mass has never been observed. However, an exact solution to the gravitational field equations with torsion is presented that does correspond to a dipole gravitational field, even though there is no negative mass. The theory is based on a non-symmetric metric tensor, and it is found there is a singularity in the metric tensor at the origin but no event horizon. Gravitational dipoles have been used to solve the dark matter problem.

gr-qc↗
arXiv2019

Gravity with spin and electromagnetism with a nonsymmetric metric tensor

It is shown the antisymmetric part of the metric tensor is the potential for the spin field. Various metricity conditions are discussed and comparisons are made to other theories, including Einstein's. It is shown in the weak field limit the theory reduces to one with a symmetric metric tensor and totally antisymmetric torsion. It is also shown, due to gauge invariance, the electromagnetic field must be present.

gr-qc↗
arXiv2014

Spin spin interaction and the relativistic Rabi formula

The interaction of an electromagnetic wave with spin (polarized light) and an electron is computed. Specifically the spin flip probability is computed using the Dirac equation for an electron trapped in a uniform magnetic field.

physics.optics↗
arXiv2013

Negative mass

Some physical aspects of negative mass are examined. Several unusual properties, such as the ability of negative mass to penetrate any armor, are analyzed. Other surprising effects include the bizarre system of negative mass chasing positive pass, naked singularities and the violation of cosmic censorship, wormholes, and quantum mechanical results as well. In addition, a brief look into the implications for strings is given.

gr-qc↗
arXiv2011

Electrodynamics with radiation reaction

The self force of electrodynamics is derived from a scalar field. The resulting equation of motion is free of all of the problems that plague the Lorentz Abraham Dirac equation. The age-old problem of a particle in a constant field is solved and the solution has intuitive appeal.

physics.class-ph↗
arXiv2009

New approach to radiation reaction in classical electrodynamics

The problem of self forces and radiation reaction is solved by conservation of energy methods. The longstanding problem of constant acceleration is solved, and it is shown that the self force does indeed affect the particle's motion, as expected on physical grounds. The relativistic generalization is also presented.

physics.class-ph↗
arXiv2008

Dark Entropy

We examine the consequences of a universe with a non-constant cosmological term in Einstein's equations and find that the Bianchi identities reduce to the first law of thermodynamics when cosmological term is identified as being proportional to the entropy density of the universe. This means that gravitating dark energy can be viewed as entropy, but more, the holographic principle along with the known expansion of the universe indicates that the entropy of the universe is growing with time and this leads to a cosmic repulsion that also grows with time. Direct implications of this result are calculated and shown to be in good accord with recent observational data.

gr-qc↗
arXiv2006

Intense ultrashort electromagnetic pulses and the equation of motion

The equations of motion of charged particles under the influence of short electromagnetic pulses are investigated. The subcycle regime is considered, and the delta function approximation is applied. The effects of the self force are also considered, and the threshold where radiation becomes important is discussed. A dimensionless parameter is defined that signals the onset of radiation reaction effects.

physics.optics↗
arXiv2006

Geometrical Origin of the Cosmological Term

Nonmetricity derived from a scalar field is shown to exist as a cosmic field, without direct coupling to matter. It leads to a variable cosmological term, a term that dominates the expansion in the early universe but dies away at later time.

gr-qc↗