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Einstein's gravitational lensing and nonlinear electrodynamics

Herman J. Mosquera Cuesta·Jose' A. de Freitas Pacheco·Jose' M. Salim
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Abstract

In 1936 Einstein predicted the phenomenon presently known as gravitational lensing (GL). A prime feature of GL is the magnification, because of the gravitational field, of the star visible surface as seen from a distant observer. We show here that nonlinear electrodynamics (NLED) modifies in a fundamental basis Einstein's general relativistic (GR) original derivation. The effect becomes apparent by studying the light propagation from a strongly magnetic ($B$) pulsar (SMP). Unlike its GR counterpart, the photon dynamics in NLED leads to a new effective GL, which depends also on the $B$-field permeating the pulsar. The apparent radius of a SMP appears then unexpectedly diminished, by a large factor, as compared to the classical Einstein's prediction. This may prove very crucial in determining physical properties of high $B$-field stars from their X-ray emission.

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Herman J. Mosquera Cuesta, Jose' A. de Freitas Pacheco, Jose' M. Salim. 2005-05-18. Einstein's gravitational lensing and nonlinear electrodynamics. https://doi.org/10.1142/s0217751x06025055

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