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arXiv · 1408.5487

Observer-dependent optical properties of stationary axisymmetric spacetimes

Donato Bini·Fernando de Felice·Andrea Geralico
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Abstract

The world lines of null particles admit arbitrary parametrizations. In the presence of a family of observers one may introduce along a null world line an extension of the so-called Cattaneo's relative standard time parameter (valid for massive particles) which plays a special role. Another possibility is to use the coordinate time itself as a parameter. The relation between relative standard time and coordinate time allows for the introduction of an observer-dependent optical path and associated refraction index. Both these quantities are studied here working out explicit examples concerning familiar null orbits and observers in black hole spacetimes.

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Donato Bini, Fernando de Felice, Andrea Geralico. 2014-08-23. Observer-dependent optical properties of stationary axisymmetric spacetimes. https://arxiv.org/abs/1408.5487

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