Power-Law Inflation Survives Observational Constraints

TL;DR

This paper revisits power-law inflation, deriving the full set of solutions consistent with current observations, thereby restoring its viability as a cosmological model and expanding its potential applications.

Contribution

It derives the complete set of analytical solutions for power-law inflation that align with modern observational constraints, challenging previous limitations.

Findings

Complete solutions satisfy observational data

Revitalizes power-law inflation as a viable model

Provides new avenues for cosmological theories

Abstract

Power-law inflation has stood as a classical model in inflationary cosmology since the early 1980s, prized for its exact analytical solutions and ability to naturally resolve the Big Bang theory's horizon and flatness problems through exponential expansion. However, its simplest form appears incompatible with modern precision observations, motivating increasingly complex alternatives. In this work, we demonstrate how previous predictions with power-law inflation considered only a particular solution of the field equations, and derive the complete set of general analytical solutions that satisfy current theoretical and observational constraints. This finding revitalizes power-law inflation as a viable framework, offering new possibilities for cosmological model-building while preserving its original mathematical elegance.