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Physics

Electromagnetic and Gravitational Waves: the Third Dimension

Plane electromagnetic and gravitational waves interact with particles in such a way as to cause them to oscillate not only in the transverse direction but also along the direction of propagation. The electromagnetic case is usually shown by use of the Hamilton-Jacobi equation and the gravitational by a transformation to a local inertial frame. Here, the covariant Lorentz force equation and the second order equation of geodesic deviation followed by the introduction of a local inertial frame are respectively used. It is often said that there is an analogy between the motion of charged particles in the field of an electromagnetic wave and the motion of test particles in the field of a gravitational wave. This analogy is examined and found to be rather limited. It is also shown that a simple special relativistic relation leads to an integral of the motion, characteristic of plane waves, that is satisfied in both cases.

Canadian Journal of Physics 89, 1187-1194 (2011).

Electromagnetic and Gravitational Waves: The Third Dimension

Physics

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Quantum Mechanics and Motion: A Modern Perspective

Physics Essays Vol. 23, pp. 242-247 (2010)

This essay is an attempted to address, from a modern perspective, the motion of a particle. Quantum mechanically, motion consists of a series of localizations due to repeated interactions that, taken close to the limit of the continuum, yields a world-line. If a force acts on the particle, its probability distribution is accordingly modified. This must also be true for macroscopic objects, although now the description is far more complicated by the structure of matter and associated surface physics.

Quantum Mechanics and Motion-A Modern Perspective

Essays in Science
Physics

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The Demystification of Emergent Behavior

Emergent behavior that appears at a given level of organization may be characterized as arising from an organizationally lower level in such a way that it transcends a mere increase in the behavioral degree of complexity. It is therefore to be distinguished from systems exhibiting chaotic behavior, for example, which are deterministic but unpredictable because of an exponential dependence on initial conditions. In emergent phenomena, higher levels of organization are not determined by lowerlevels of organization; or, more colloquially, emergent behavior is often said to be “greater than the sum of the parts”. The concept plays an especially important but contentious role in the biological sciences. This essay is intended to demystify at least some aspects of the mystery of emergence.

(This is an updated and expanded version of the original post with some portions rewritten to enhance clarity.)

EMERGENT BEHAVIOR

Biology
Essays in Science
General Interest
Physics

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Charge, geometry, and effective mass in the Kerr-Newman solution to the Einstein field equations

Foundations of Physics Vol. 38, pp. 959-968 (2008)

The original publication is available at www.springerlink.com

http://dx.doi.org/10.1007/s10701-008-9245-x

It has been shown that for the Reissner-Nordstrom solution to the vacuum Einstein field equations charge, like mass, has a unique space-time signature [Found. Phys. 38, 293-300 (2008)]. The presence of charge results in a negative curvature. This work, which includes a discussion of effective mass, is extended here to the Kerr-Newman solution.

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Physics

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Negative Energies and Field Theory

The assumption that the vacuum is the minimum energy state, invariant under unitary transformations, is fundamental to quantum field theory. However, the assertion that the conservation of charge implies that the equal time commutator of the charge density and its time derivative vanish for two spatially separated points is inconsistent with the requirement that the vacuum be the lowest energy state. Yet, for quantum field theory to be gauge invariant, this commutator must vanish. This essay explores how this conundrum is resolved in quantum electrodynamics.
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Physics

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The Vacuum and the Cosmological Constant Problem

It will be argued here that the cosmological constant problem exists because of the way the vacuum is defined in quantum field theory. It has been known for some time that for QFT to be gauge invariant certain terms—such as part of the vacuum polarization tensor must be eliminated either explicitly or by some form of regularization followed by renormalization. It has recently been shown that lack of gauge invariance is a result of the way the vacuum is defined, and redefining the vacuum so that the theory is gauge invariant may also offer a solution to the cosmological constant problem.

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Physics

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Charge, geometry, and effective mass

Foundations of Physics Vol. 38, pp. 293-300 (2008).

The original publication is available at www.springerlink.com

http://dx.doi.org/10.1007/s10701-008-9209-1

Charge, like mass in Newtonian mechanics, is an irreducible element of electromagnetic theory that must be introduced ab initio. Its origin is not properly a part of the theory. Fields are then defined in terms of forces on either masses–in the case of Newtonian mechanics, or charges in the case of electromagnetism. General Relativity changed our way of thinking about the gravitational field by replacing the concept of a force field with the curvature of space-time. Mass, however, remained an irreducible element. It is shown here that the Reissner-Nordstrom solution to the Einstein field equations tells us that charge, like mass, has a unique space-time signature.

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Physics

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The Infinite Red-Shift Surfaces of the Kerr Solution

In contrast to the Schwarzschild solution, the infinite red shift surfaces and null surfaces of the Kerr solution to the axially-symmetric Einstein field equations are distinct. Some unusual infinite red shift surfaces for observers following the time-like Killing vector are displayed here for the Kerr and Kerr-Newman solution. Some similarities of the latter to the Reissner-Nordstrom solution are also discussed.

(arXiv: gr-qc/0702114)

Journal of Physics & Astronomy Vol. 2, Issue 4.

JOPA_InfRedShiftSurf

Physics

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Forum on Physics and Society of the American Physical Society

Articles appearing in Physics & Society

Bombs, Reprocessing, and Reactor-Grade Plutonium (April 2006)
Coauthor: George S. Stanford (PDF)

Nuclear Power and Proliferation (January 2006)
Coauthor: George S. Stanford (PDF)

Purex and Pyro are not the Same (July 2004)
Coauthors: William H. Hannum and George S. Stanford (PDF)

Gaps in the APS Position on Nuclear Energy (April 2002)
Coauthor: George S. Stanford (PDF)

Nuclear Policy
Physics
Politics

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Topology in Electromagnetics

Topology in Electromagnetics is a chapter in Frontiers in Electromagnetics, edited by Douglas H. Werner and Raj Mittra (The Institute of Electrical and Electronics Engineers, Inc., 2000).

The link to the book is:

http://www.amazon.com/Frontiers-Electromagnetics-Series-Microwave-Technology/dp/0780347013

 

Books
Physics

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