Abraham-Minkowski controversy

This MedLibrary.org supplementary page on Abraham-Minkowski controversy is provided directly from the open source Wikipedia as a service to our readers. Please see the note below on authorship of this content, as well as the Wikipedia usage guidelines. To search for other content from our encyclopedia supplement, please use the form below:

The Abraham-Minkowski controversy is a physics debate concerning electromagnetic momentum within dielectric media. The preponderance of evidence in the debate suggests that the Abraham equation is correct1, but some investigators disagree.

Two equations exist describing momentum transfer between matter and electromagnetic fields. Both seem to be supported by contradicting experimental data. The two existing equations were first suggested by Max Abraham and Hermann Minkowski, from which the controversy name derives. Both define the momentum of an electromagnetic field permeating matter. Abraham's equation suggests that in materials through which light travels more slowly, electromagnetic fields should have lower momentum, while Minkowski suggests it should have a greater momentum. Minkowski suggested that Abraham only accounted for the momentum of the electromagnetic fields, and his equation was an attempt to take into account the momentum of the material as well. More recent work suggests that this characterization is incorrect.

At least one report has suggested Minkowski's formulation, if correct, would provide the physical base for reactionless drive.2 However, an independent review from the Air Force Academy concluded that there would be no expected net propulsive forces, and a NASA report determined that "The signal levels are not sufficiently above the noise as to be conclusive proof of a propulsive effect."3

The two equations for the momentum in a dielectric with refractive index n are:

  • The Minkowski version is: nhf/c
  • The Abraham version is: hf/(nc)

where h is the Planck constant, f is the frequency of the light and c is the speed of light in vacuum.

See also

References

  1. ^ Quantum vacuum contribution to the momentum of dielectric media, A. Feigel, PHYSICAL REVIEW LETTERS 92 (2): Art. No. 020404 JAN 16 2004
  2. ^ Propellantless Propulsion by Electromagnetic Inertia Manipulation: Theory and Experiment by Hector Hugo Brito
  3. ^ NASA and DoD Report on Prospects for Breakthrough Propulsion From Physics

External links

Wikipedia content modification information:

  • This page was last modified on 25 October 2008, at 13:17.

Wikipedia Authorship and Review

Wikipedia content provided here is not reviewed directly by MedLibrary.org. Wikipedia content is authored by an open community of volunteers and is not produced by or in any way affiliated with MedLibrary.org.

Wikipedia Usage Guidelines

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article on "Abraham-Minkowski controversy".

The URL for this specific entry is:

All Wikipedia text is available under the terms of the GNU Free Documentation License. (See Copyrights for details). Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc.