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Universe 2016, 2(4), 26;

A Solution of the Mitra Paradox

Oslo and Akershus University College of Applied Sciences, Faculty of Technology, Art and Sciences, PB 4 St. Olavs. Pl., NO-0130 Oslo, Norway
Academic Editors: Lorenzo Iorio and Elias C. Vagenas
Received: 7 September 2016 / Revised: 27 October 2016 / Accepted: 1 November 2016 / Published: 4 November 2016
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The “Mitra paradox” refers to the fact that while the de Sitter spacetime appears non-static in a freely falling reference frame, it looks static with reference to a fixed reference frame. The coordinate-independent nature of the paradox may be gauged from the fact that the relevant expansion scalar, θ = 3 Λ , is finite if Λ > 0 . The trivial resolution of the paradox would obviously be to set Λ = 0 . However, here it is assumed that Λ > 0 , and the paradox is resolved by invoking the concept of “expansion of space”. This is a reference-dependent concept, and it is pointed out that the solution of the Mitra paradox is obtained by taking into account the properties of the reference frame in which the coordinates are co-moving. View Full-Text
Keywords: general theory of relativity; exact solutions; spherical symmetry; physical interpretation general theory of relativity; exact solutions; spherical symmetry; physical interpretation
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

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Grøn, Ø. A Solution of the Mitra Paradox. Universe 2016, 2, 26.

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