From geometry to cosmology: a pedagogical review of inflation in curvature, torsion, and extended gravity theories

Abstract

We present a simplified review of inflationary cosmology across various modified gravity theories. These include models based on curvature, torsion, and non-metricity. We explore how scalar fields interact with different geometric quantities and how these interactions affect inflationary dynamics. Key cosmological features such as background evolution, reheating, and observable parameters are discussed. We also examine exotic scenarios inspired by string theory, extra dimensions, and non-local models. This work aims to connect theoretical models with observational data and future missions, offering guidance for exploring inflation beyond general relativity.

This manuscript has been withdrawn by the author. Following publication of a related journal version, verification issues were identified, including problems with cited references and factual consistency. To maintain the integrity of the scientific record, the author has chosen to withdraw this preprint