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Updated: Dec 16, 2025
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Setting Limits on Supersymmetry Using Simplified Models
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Relaxing the TCC bound on inflationary cosmology?
Vahid Kamali1,2,3, Robert Brandenberger1
1Department of Physics, McGill University, Montreal, QC H3A 2T8 Canada.
The European Physical Journal. C, Particles and Fields
|July 7, 2020
Summary
The study shows that inflation energy scales and tensor-to-scalar ratios may be less constrained. This is possible if the universe
Area of Science:
- Cosmology
- Theoretical Physics
Background:
- Cosmic inflation is a theoretical framework explaining the early universe.
- Current models impose strict upper bounds on inflation's energy scale and the tensor-to-scalar ratio.
Purpose of the Study:
- To investigate if relaxing these bounds is possible under modified cosmological conditions.
- To explore alternative scenarios for the universe's early expansion.
Main Methods:
- Theoretical analysis of cosmological models.
- Examining the implications of a changing equation of state during inflation.
Main Results:
- Demonstrates that strict upper bounds on inflation energy and tensor-to-scalar ratio can be relaxed.
- This relaxation is contingent on a post-slow roll phase of near-marginal acceleration.
Conclusions:
- The findings suggest flexibility in early universe parameters under specific conditions.
- However, constructing a natural model for this scenario remains challenging.
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