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Constraining barrow entropy-based cosmology with power-law inflation
1Applied Physics Section of Environmental Science Department, Escola Politècnica Superior, Universitat de Lleida, Av. Jaume II, 69, 25001 Lleida, Spain.
The European Physical Journal. C, Particles and Fields
|May 2, 2023
Summary
This study explores cosmic inflation using Barrow entropy, a modification of standard thermodynamics. Barrow entropy is incompatible with kinetic inflation but allows for a slow-roll phase, with new constraints derived from Planck data.
Area of Science:
- Cosmology
- Thermodynamics
- Quantum Gravity
Background:
- The standard Bekenstein-Hawking entropy is used in black hole thermodynamics.
- Barrow entropy incorporates quantum gravitational effects on horizon surfaces.
- Modified gravity-thermodynamics conjectures offer alternative cosmological models.
Purpose of the Study:
- To investigate the inflationary era in a modified cosmological scenario using Barrow entropy.
- To derive modified Friedmann equations based on the first law of thermodynamics.
- To analyze the impact of Barrow entropy on inflationary dynamics and compare with observational data.
Main Methods:
- Applied the first law of thermodynamics to the apparent horizon of a Friedmann-Robertson-Walker Universe.
- Assumed a power-law behavior for the scalar inflaton field.
- Constrained the Barrow exponent using observational consistency with Planck data for scalar spectral index and tensor-to-scalar ratio.
Main Results:
- Modified Friedmann equations were extracted for the Barrow cosmological setup.
- Barrow entropy was found to be incompatible with kinetic inflation.
- The inflationary era can phenomenologically consist of a slow-roll phase.
- The Barrow exponent was constrained to a stringent bound () consistent with Planck data.
Conclusions:
- Barrow entropy offers a modified framework for studying cosmic inflation.
- The slow-roll phase of inflation is compatible with Barrow entropy.
- The derived constraints on the Barrow exponent provide significant observational validation for this modified cosmological scenario.
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