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arXiv · 2106.06740

Conflict between some higher-order curvature invariant terms

Dalia Saha·Mohosin Alam·Ranajit Mandal·Abhik Kumar Sanyal
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Abstract

A viable quantum theory does not allow curvature invariant terms of different higher orders to be accommodated in the gravitational action. We show that there is indeed a conflict between the curvature squared and Gauss-Bonnet squared terms from the point of view of hermiticity. This means one should choose either, in addition to the Einstein-Hilbert term, but never the two together. We explore early cosmic evolution with Gauss-Bonnet squared term.

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Dalia Saha, Mohosin Alam, Ranajit Mandal, Abhik Kumar Sanyal. 2021-06-12. Conflict between some higher-order curvature invariant terms. https://doi.org/10.1016/j.nuclphysb.2021.115570

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