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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Large-scale suppression from stochastic inflation.
Florian Kühnel1, Dominik J Schwarz
1Fakultät für Physik, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, Germany. kuehnel@physik.uni-bielefeld.de
Physical Review Letters
|January 15, 2011
Summary
The power spectrum of self-interacting scalar fields in de Sitter spacetime is suppressed on large scales. This suppression prevents infrared divergences in field fluctuation correlations.
Area of Science:
- Cosmology
- Quantum Field Theory
Background:
- Scalar fields are fundamental in cosmological models.
- Self-interactions can significantly alter field behavior.
- De Sitter spacetime is a model for cosmic inflation.
Purpose of the Study:
- To investigate the power spectrum of self-interacting scalar fields in de Sitter spacetime.
- To analyze the impact of self-coupling on large-scale structures.
- To address infrared divergences in correlation functions.
Main Methods:
- Nonperturbative analysis of the power spectrum.
- Calculation of the cutoff scale based on coupling strength and expansion rate.
- Examination of the two-point correlation function.
Main Results:
- The power spectrum is strongly suppressed on large scales.
- A cutoff scale is identified, dependent on self-coupling and cosmic expansion.
- The two-point correlation function is free from infrared divergences.
Conclusions:
- Self-interactions regularize the power spectrum on large scales.
- The findings have implications for understanding early universe cosmology.
- The study provides a mechanism to avoid theoretical inconsistencies.
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