Magnetic Energy, Multiply-Connected Domains, and Force-Free Fields

Phys. Rev. A Vol. 46, p. 2117 (1992) (PDF)

This paper addresses the question of magnetic energy in multiply connected domains. It is shown that the magnetic energy must in general include a boundary term that is usually assumed to vanish. The physical interpretation of this term is discussed in terms of De Rham’s theorems.

Physics

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Axially Symmetric Solutions to the Force-Free Magnetic Field Equations in Spherical and Cylindrical Coordinates

Phys. Rev. A Vol. 45, p. 7520 (1992) (PDF)

The force-free magnetic field condition is expressed in terms of a flux function; alpha is then also a function of the flux function, and with suitable restrictions the resulting equations can be separated and solved. The case of spherical coordinates yields four sets of solutions which are shown to be dependent and equivalent to a simple generalization of those given by Chandrasekhar [Proc. Natl. Acad Sci. USA Vol. 42, 1 (1956)]. Similarly, the case of cylindrical coordinates results in a generalization of the solution given by Furth, et al. [Rev. Sci. Instrum. Vol. 28, 949 (1957)].

Physics

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A Class of Cylindrically Symmetric Solutions to the Force-Free Magnetic Field Equations with Non-Constant Alpha

J. Appl. Phys. Vol. 68, p. 3818 (1990) (PDF)

The general approach to cylindrically symmetric force-free magnetic fields first introduced by Lüst and Schlüter [Z. Astrophys. Vol. 34, 263 (1954)], is restricted to cylindrically symmetric fields, and subsequently used to determine a set of solutions to the force-free field equations with non-constant alpha. The first element of the set is the well known constant a solution of Lundquist [Ark. Fys. Vol. 2, 361 (1951)]. These solutions may have practical applications with respect to high-temperature superconductors.

Physics

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A Simplified Anti-Submarine Warfare Problem Treated as a Steady-State Markov Process

Applied Physics Communications Vol 8, p. 227 (1988)
Coauthor: Robert Piacesi
[A shortened version of this article also appeared in Physics & Society (January 1989)]

Markov processes represent a powerful method for quantifying questions related to the survivability of strategic nuclear forces. This paper gives an elementary introduction to Markow processes and chains followed by a simple anti-submarine warfare example in which the scenario of a surveillance-surge attack is treated as a steady state Markov process.

(MS Word Document)

Nuclear Policy
Physics

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Yields of US and Soviet Nuclear Tests

Physics Today Vol. 40, p. 36 (August 1987) Part 1(PDF) Part 2 (PDF)
Coauthor: Jack Evernden

Failure to account properly for geological and seismological differences between the US and Soviet test sites has led to overestimates of Soviet tests and to incorrect claims of Soviet cheating on the treaty limit of 150 kilotons.

Nuclear Policy
Physics
Politics

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Accelerator System for a 1-Million Volt Scanning Transmission Electron Microscope

Reviews of Scientific Instruments, Vol 48, p. 841 (1977)

The accelerator, magnetic shielding-equipotential grading system, and voltage divider chain of the University of Chicago 1-MV STEM are described. A dynamical analysis of the system is presented in addition to a discussion of the problem of “electron loading” encountered while conditioning the accelerator tube.

(PDF)

Physics

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Does a Gravitational Red Shift Necessarily Imply Space-Time Curvature?

American Journal of Physics, Vol. 43, p. 266 (1975)
Coauthor: Charles Nissim-Sabat

We show that no argument that attempts to infer space-time curvature solely from the gravitational red shift can be valid.

(PDF)

Physics

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Uniform Magnetic Fields and the Problem of the Ellipsoid

Journal of Applied Physics, Vol. 46, p. 3178 (1975)

The problem of obtaining a uniform magnetic field within a nondegenerate ellipsoid by the use of an appropriate surface current distribution is solved.

(PDF)

Physics

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