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arXiv · astro-ph/0411754

Negative phase velocity of electromagnetic waves and the cosmological constant

Tom G. Mackay·Sandi Setiawan·Akhlesh Lakhtakia
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Abstract

Examining the propagation of electromagnetic plane waves with the wavevector directed in opposition to the time-averaged Poynting vector in cosmological spacetime with piecewise uniform metric, we show that such negative-phase-velocity (NPV) propagation is possible in certain de Sitter spacetimes but not in anti-de Sitter spacetimes. This difference suggests the possibility of an optical/electromagnetic experiment to discern the cosmological constant of a four-dimensional universe stemming from a five-dimensional brane universe.

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Tom G. Mackay, Sandi Setiawan, Akhlesh Lakhtakia. 2005-03-15. Negative phase velocity of electromagnetic waves and the cosmological constant. https://doi.org/10.1140/epjcd%2Fs2005-01-001-9

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