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arXiv · 1801.06683

Gravitational wave speed: Implications for models without a mass scale

Henrik Nersisyan·Nelson A. Lima·Luca Amendola
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Abstract

The recent report that the gravitational wave speed equals the light speed puts strong constraints on the anisotropic stress parameter of many modified gravity models, a quantity that is directly observable through large-scale structure. We show here that models without a mass scale completely escape these constraints. We discuss a few relevant cases in detail: Brans-Dicke theory, nonlocal models, and Galileon Lagrangian.

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Henrik Nersisyan, Nelson A. Lima, Luca Amendola. 2018-01-20. Gravitational wave speed: Implications for models without a mass scale. https://arxiv.org/abs/1801.06683

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