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arXiv · 1101.2841

Palatini Actions and Quantum Gravity Phenomenology

Gonzalo J. Olmo
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Abstract

We show that an invariant an universal length scale can be consistently introduced in a generally covariant theory through the gravitational sector using the Palatini approach. The resulting theory is able to capture different aspects of quantum gravity phenomenology in a single framework. In particular, it is found that in this theory field excitations propagating with different energy-densities perceive different background metrics, which is a fundamental characteristic of the DSR and Rainbow Gravity approaches. We illustrate these properties with a particular gravitational model and explicitly show how the {\it soccer ball problem} is avoided in this framework. The isotropic and anisotropic cosmologies of this model also avoid the big bang singularity by means of a big bounce.

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Gonzalo J. Olmo. 2011-01-14. Palatini Actions and Quantum Gravity Phenomenology. https://doi.org/10.1088/1475-7516/2011/10/018

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