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arXiv · 2203.16610

Contemplating the fate of modified gravity

Alexey Golovnev·Maria-Jose Guzman
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Abstract

Possible models of modified gravity are being extensively studied now, with most phenomenological motivations coming from puzzles and tensions in cosmology due to a natural desire to better fit the known and newly coming data. At the same time, available experimental evidence is limited for testing gravity as a force beyond the regimes in which the theory of general relativity has proven to be successful. This situation leads researchers to look for ``the simplest modification'' to general relativity in a certain class of models, which is enough to solve one or more problems. As a result, we are lost amid a variety of theories with no deeper guiding principle. We give a general review of existing approaches and discuss the current state of the art.

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Alexey Golovnev, Maria-Jose Guzman. 2022-03-30. Contemplating the fate of modified gravity. https://doi.org/10.3390/universe10020066

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