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Szekeres universes with homogeneous scalar fields
John D Barrow1, Andronikos Paliathanasis2,3,4
11DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Rd., Cambridge, CB3 0WA UK.
The European Physical Journal. C, Particles and Fields
|April 9, 2019
Summary
This study explores the "inflaton" field within the Szekeres cosmological metric, revealing stable solutions for accelerating, spatially-flat Friedmann–Lemaître–Robertson–Walker geometries. These findings advance our understanding of cosmic inflation and spacetime evolution.
Area of Science:
- Cosmology
- General Relativity
- Theoretical Physics
Background:
- The Szekeres metric describes inhomogeneous cosmological models.
- Homogeneous scalar fields, or
Purpose of the Study:
- To investigate the existence and stability of cosmological solutions within the Szekeres metric using an
Main Methods:
- Reduced gravitational field equations for the Szekeres metric with a homogeneous scalar field.
- Analyzed two families of solutions: Kantowski-Sachs and inhomogeneous FLRW-like spacetimes.
- Investigated solution stability by examining critical points of the field equations.
Main Results:
- Identified two families of solutions, differing from pressure-free Szekeres spacetimes.
- Found stable solutions corresponding to accelerating, spatially-flat Friedmann–Lemaître–Robertson–Walker geometries.
- Characterized the behavior of the homogeneous scalar field in these solutions.
Conclusions:
- The Szekeres metric, with an inflaton field, can support stable, accelerating FLRW cosmologies.
- This work provides insights into the early universe and the dynamics of scalar fields in cosmology.
- Highlights the importance of considering scalar fields in inhomogeneous cosmological models.
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