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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
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Cosmology Meets Functional QCD: First-Order Cosmic QCD Transition Induced by Large Lepton Asymmetries.
Fei Gao1, Isabel M Oldengott2,3
1Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 16, 69120 Heidelberg, Germany.
Physical Review Letters
|April 15, 2022
Summary
Large lepton flavor asymmetries may trigger a first-order cosmic Quantum Chromodynamics (QCD) transition. This study calculates the cosmic trajectory during the QCD epoch, revealing conditions for this early Universe phase transition.
Area of Science:
- Cosmology
- Particle Physics
- Quantum Chromodynamics (QCD)
Background:
- Lepton flavor asymmetries in the early Universe are largely unconstrained before neutrino oscillations.
- Understanding the cosmic QCD epoch is crucial for early Universe cosmology.
Purpose of the Study:
- To investigate the cosmic trajectory during the QCD epoch with large lepton flavor asymmetries.
- To explore the possibility of a first-order cosmic QCD phase transition under these conditions.
Main Methods:
- Calculation of the cosmic trajectory incorporating large lepton flavor asymmetries.
- Inclusion of thermodynamic quantities from functional QCD methods.
- Analysis of benchmark scenarios to determine conditions for a first-order transition.
Main Results:
- The study reveals, for the first time, the potential for a first-order cosmic QCD transition.
- Specific values of lepton flavor asymmetries required for this first-order transition are identified.
Conclusions:
- Large lepton flavor asymmetries can fundamentally alter the nature of the cosmic QCD transition.
- This research opens new avenues for probing early Universe physics through cosmological observations.
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