Publications de Andrey Shkerin

Preheating in Palatini Higgs inflation on the lattice

Andrey Shkerin, Inar Timiryasov, Juraj Klaric, Adrien Florio

We study preheating following Higgs inflation in the Palatini formulation of gravity. We numerically evolve perturbations of the radial mode of the Higgs field and that of three scalars modeling the gauge bosons. We compare the two non-perturbative mechani ...

IOP Publishing Ltd2022

Einstein-Cartan Portal to Dark Matter

Mikhail Chapochnikov, Andrey Shkerin, Inar Timiryasov, Sebastian Zell

It is well known since the works of Utiyama and Kibble that the gravitational force can be obtained by gauging the Poincare group, which puts gravity on the same footing as the standard model fields. The resulting theory-Einstein-Cartan gravity-inevitably ...

AMER PHYSICAL SOC2021

Standard model meets gravity: Electroweak symmetry breaking and inflation

Mikhail Chapochnikov, Andrey Shkerin, Sebastian Zell

We propose a model for combining the Standard Model (SM) with gravity. It relies on a nonminimal coupling of the Higgs field to the Ricci scalar and on the Palatini formulation of gravity. Without introducing any new degrees of freedom in addition to those ...

American Physical Society2021

Einstein-Cartan gravity, matter, and scale-invariant generalization (vol 10, 177, 2020)

Mikhail Chapochnikov, Andrey Shkerin, Inar Timiryasov, Sebastian Zell

Springer Nature2021

Higgs inflation in Einstein-Cartan gravity

Mikhail Chapochnikov, Andrey Shkerin, Inar Timiryasov, Sebastian Zell

We study inflation driven by the Higgs field in the Einstein-Cartan formulation of gravity. In this theory, the presence of the Holst and Nieh-Yan terms with the Higgs field non-minimally coupled to them leads to three additional coupling constants. For a ...

IOP PUBLISHING LTD2021

Higgs inflation in Einstein-Cartan gravity (vol 02, 008, 2021)

Mikhail Chapochnikov, Andrey Shkerin, Inar Timiryasov, Sebastian Zell

IOP Publishing Ltd2021

Matter matters in Einstein-Cartan gravity

Mikhail Chapochnikov, Andrey Shkerin, Georgios Karananas, Sebastian Zell

We study scalar, fermionic and gauge fields coupled nonminimally to gravity in the Einstein-Cartan formulation. We construct a wide class of models with nondynamical torsion whose gravitational spectra comprise only themassless graviton. Eliminating nonpro ...

American Physical Society2021

Quantum effects in Palatini Higgs inflation

Mikhail Chapochnikov, Andrey Shkerin, Sebastian Zell

We study quantum effects in Higgs inflation in the Palatini formulation of gravity, in which the metric and connection are treated as independent variables. We exploit the fact that the cutoff, above which perturbation theory breaks down, is higher than th ...

IOP PUBLISHING LTD2020

Review of Nontopological Solitons in Theories with U(1)-Symmetry

Andrey Shkerin

We provide a review of nontopological solitonic solutions arising in theories with a complex scalar field and global or gauge U(1)-symmetry. It covers Q-balls, homogeneous charged scalar condensates, and nonlinear localized holes and bulges in a classicall ...

2020

Einstein-Cartan gravity, matter, and scale-invariant generalization

Mikhail Chapochnikov, Andrey Shkerin, Inar Timiryasov, Sebastian Zell

We study gravity coupled to scalar and fermion fields in the Einstein-Cartan framework. We discuss the most general form of the action that contains terms of mass dimension not bigger than four, leaving out only contributions quadratic in curvature. By res ...

Springer Nature2020