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arXiv · 0807.1854

DSR as an explanation of cosmological structure

Joao Magueijo
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Abstract

Deformed special relativity (DSR) is one of the possible realizations of a varying speed of light (VSL). It deforms the usual quadratic dispersion relations so that the speed of light becomes energy dependent, with preferred frames avoided by postulating a non-linear representation of the Lorentz group. The theory may be used to induce a varying speed of sound capable of generating (near) scale-invariant density fluctuations, as discussed in a recent Letter. We identify the non-linear representation of the Lorentz group that leads to scale-invariance, finding a universal result. We also examine the higher order field theory that could be set up to represent it.

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Joao Magueijo. 2008-07-11. DSR as an explanation of cosmological structure. https://doi.org/10.1088/0264-9381%2F25%2F20%2F202002

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