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arXiv · 2408.01854

Introduction to the number of $e$-folds in slow-roll inflation

Alessandro Di Marco·Emanuele Orazi·Gianfranco Pradisi
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Abstract

In this review, a pedagogical introduction to the concepts of slow-roll inflationary Universe and number of $e$-folds is provided. In particular, the differences between the basic notion of number of $e$-folds ($N_e$), total number of $e$-folds ($N_T$) and number of $e$-folds before the end of inflation ($N$), are outlined. The proper application of the number of $e$-folds before the end of inflation is discussed both as a time-like variable for the scalar field evolution and as a key parameter for computing inflationary predictions.

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Alessandro Di Marco, Emanuele Orazi, Gianfranco Pradisi. 2024-08-03. Introduction to the number of $e$-folds in slow-roll inflation. https://doi.org/10.3390/universe10070284

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