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Cosmic Optical Activity in a Randall-Sundrum Braneworld with Bulk Kalb-Ramond field

Debaprasad Maity·Soumitra SenGupta
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Abstract

Optical activity of electromagnetic waves in a string inspired Kalb-Ramond cosmological background is studied in presence of extra spacetime dimension. The Kalb-Ramond-electromagnetic coupling which originates from the gauge anomaly cancelling Chern-Simons term in a string inspired model, is explicitly calculated following Randall-Sundrum braneworld conjecture. It is shown that the Randall-Sundrum scenario leads to an enormous enhancement of the optical rotation of a plane polarized electromagnetic wave propagating on the visible brane.Absence of any experimental support in favour of such a large rotation in astrophysical experiments on distant galactic radio waves indicates an apparent conflict between Randall-Sundrum brane world scenario and the presence of Kalb-Ramond antisymmetric tensor field in the background spacetime.

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Debaprasad Maity, Soumitra SenGupta. 2004-06-02. Cosmic Optical Activity in a Randall-Sundrum Braneworld with Bulk Kalb-Ramond field. https://doi.org/10.1088/0264-9381%2F21%2F14%2F004

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