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Einstein-Cartan Portal to Dark Matter.
Mikhail Shaposhnikov1, Andrey Shkerin1, Inar Timiryasov1
1Institute of Physics, Laboratory for Particle Physics and Cosmology, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
Physical Review Letters
|May 7, 2021
Summary
Gravitational gauging of the Poincaré group leads to Einstein-Cartan gravity. This theory explains a novel mechanism for producing singlet fermions, which can act as dark matter particles across a wide mass range.
Area of Science:
- Theoretical Physics
- Cosmology
- Particle Physics
Background:
- The Poincaré group can be gauged to derive gravity, unifying it with standard model interactions.
- This leads to Einstein-Cartan gravity, incorporating torsion and associated fermionic interactions.
Purpose of the Study:
- To investigate a novel mechanism for producing singlet fermions in the early Universe.
- To explore the potential of these fermions as dark matter candidates.
Main Methods:
- Analysis of four-fermion and scalar-fermion interactions arising from Einstein-Cartan gravity.
- Examination of the production mechanism for singlet fermions in the early Universe.
Main Results:
- Identified a new mechanism for generating singlet fermions via gravity-induced interactions.
- These fermions can constitute dark matter over a broad mass spectrum (keV to ~10^8 GeV).
Conclusions:
- The proposed mechanism offers a viable pathway for dark matter production.
- Observational signatures, particularly for keV-scale dark matter (e.g., right-handed neutrinos), are discussed.
- Primordial dark matter momentum distribution could reveal these gravity-induced fermionic interactions.
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