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arXiv · 1912.10412

Non-Riemannian Volume Elements Dynamically Generate Inflation

David Benisty·Eduardo Guendelman·Emil Nissimov·Svetlana Pacheva
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Abstract

Our primary objective is the formulation of a plausible cosmological inflationary model entirely in terms of a pure modified gravity without any a priori matter couplings within the formalism of non-Riemannian spacetime volume elements. The non-Riemannian volume elements dynamically create in the physical Einstein frame a canonical scalar matter field and produce a non-trivial inflationary scalar potential with a large flat region and a low-lying stable minimum corresponding to the late universe stage. This dynamically generated inflationary potential is a substantial generalization of the classic Starobinsky potential. Our model predicts scalar power spectral index and tensor to scalar ratio in accordance with the available observational data.

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David Benisty, Eduardo Guendelman, Emil Nissimov, Svetlana Pacheva. 2019-12-22. Non-Riemannian Volume Elements Dynamically Generate Inflation. https://arxiv.org/abs/1912.10412

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