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arXiv · 1808.07897

Towards the nonlinear regime in extensions to GR: assessing possible options

Gwyneth Allwright·Luis Lehner
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Abstract

Testing General Relativity and exploring possible departures has received further input with the possibility to do so through gravitational waves emitted in strongly gravitating/highly dynamical scenarios and also through the availability of exquisitely sensitive cosmological observations. However, most extensions suffer from severe pathologies at the mathematical level which have stymied a thorough exploration of putative theories. With the aid of a model problem which captures typical pathologies, we explore suggested methods to control them. We find that the approach that modifies the equations to control higher-order gradients is both robust and efficient.

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Gwyneth Allwright, Luis Lehner. 2018-08-23. Towards the nonlinear regime in extensions to GR: assessing possible options. https://doi.org/10.1088/1361-6382%2Fab0ee1

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