Publications associées à Minimal coupling

Emergent order in hydrodynamic spin lattices

Macroscale analogues(1-3) of microscopic spin systems offer direct insights into fundamental physical principles, thereby advancing our understanding of synchronization phenomena(4) and informing the design of novel classes of chiral metamaterials(5-7). He ...

NATURE PORTFOLIO2021

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

Dilaton-assisted generation of the Fermi scale from the Planck scale

Andrey Shkerin

In scale-invariant theories of gravity the Planck mass M-p, which appears due to spontaneous symmetry breaking, can be the only scale at the classical level. It was argued that the second scale can be generated by a quantum nonperturbative gravitational ef ...

American Physical Society2019

Probing Molecular Chirality by Orbital-Angular-Momentum-Carrying X-ray Pulses

Jérémy Raymond Jean Maurice Rouxel

A twisted X-ray beam with orbital angular momentum is employed in a theoretical study to probe molecular chirality. A nonlocal response description of the matter-field coupling is adopted to account for the field short wavelength and the structured spatial ...

AMER CHEMICAL SOC2019

Chiral charge dynamics in Abelian gauge theories at finite temperature

Mikhail Chapochnikov, Daniel Garcia Figueroa, Adrien Florio

We study fermion number non-conservation (or chirality breaking) in Abelian gauge theories at finite temperature. We consider the presence of a chemical potential mu for the fermionic charge, and monitor its evolution with real-time classical lattice simul ...

Springer Nature2019

Kinetic approach to the Schwinger effect during inflation

Oleksandr Sobol

Using the kinetic approach, we study the impact of the charged particle dynamics due to the Schwinger effect on the electric field evolution during inflation. As a simple model of the electric field generation, we consider the kinetic coupling of the elect ...

American Physical Society2019

Gravity, scale invariance and the hierarchy problem

Mikhail Chapochnikov, Andrey Shkerin

Combining the quantum scale invariance with the absence of new degrees of freedom above the electroweak scale leads to stability of the latter against perturbative quantum corrections. Nevertheless, the hierarchy between the weak and the Planck scales rema ...

Springer Nature2018

Euclidean classical solutions in quantum field theory and gravity: Higgs vacuum metastability and the hierarchy problem

Andrey Shkerin

The thesis is dedicated to two groups of questions arising in modern particle physics and cosmology. The first group concerns with the problem of stability of the electroweak (EW) vacuum in different environments. Due to its phenomenological significance, ...

EPFL2018

Conformal symmetry: Towards the link between the Fermi and the Planck scales

Mikhail Chapochnikov, Andrey Shkerin

If the mass of the Higgs boson is put to zero, the classical Lagrangian of the Standard Model (SM) becomes conformally invariant (CI). Taking into account quantum non-perturbative QCD effects violating CI leads to electroweak symmetry breaking with the sca ...

ELSEVIER SCIENCE BV2018

Magnetogenesis In Natural Inflation Model

Oleksandr Sobol

We study the process of inflationary magnetogenesis in the natural single-field inflation model, whose parameters are chosen in accordance with the recent observations by the Planck collaboration [1]. The conformal invariance of the Maxwell action is broke ...

BOGOLYUBOV INST THEORETICAL PHYSICS NATL ACAD SCI UKRAINE2018

Influence of backreaction of electric fields and Schwinger effect on inflationary magnetogenesis

Oleksandr Sobol

We study the generation of electromagnetic fields during inflation when the conformal invariance of Maxwell's action is broken by the kinetic coupling f(2)(phi)F mu nu F mu nu of the electromagnetic field to the inflaton field phi We consider the case wher ...

American Physical Society2018

All-in-all-Out Magnetic Order and Propagating Spin Waves in Sm2Ir2O7

Using resonant magnetic x-ray scattering we address the unresolved nature of the magnetic ground state and the low-energy effective Hamiltonian of Sm2Ir2O7, a prototypical pyrochlore iridate with a finite temperature metal-insulator transition. Through a c ...

American Physical Society2016

Measuring absolute spin polarization in dissolution-DNP by Spin PolarimetrY Magnetic Resonance (SPY-MR)

Geoffrey Bodenhausen, Aurélien Bornet, Sami Jannin, Jonas Milani, Basile Vuichoud, Quentin Chappuis

Dynamic nuclear polarization at 1.2 K and 6.7 T allows one to achieve spin temperatures on the order of a few millikelvin, so that the high-temperature approximation (Delta E < kT) is violated for the nuclear Zeeman interaction Delta E = gamma B(0)h/(2 pi) ...

Academic Press Inc - Elsevier Science2015

On the strong coupling scale in Higgs G-inflation

Kohei Kamada

Higgs G-inflation is an inflation model that takes advantage of a Galileon-like derivative coupling. It is a non-renormalizable operator and is strongly coupled at high energy scales. Perturbative analysis does not have a predictive power any longer there. ...

Elsevier2015

Magnetization plateaux in an extended Shastry-Sutherland model

Frédéric Mila, Julien Dorier

We study an extended two-dimensional Shastry-Sutherland model in a magnetic field where besides the usual Heisenberg exchanges of the Shastry-Sutherland model two additional SU(2) invariant couplings are included. Perturbative continous unitary transformat ...

2009

Measurement of the running of the electromagnetic coupling at large momentum-transfer at LEP

Aurelio Bay, Qian Wang, Horst Vogel, Eduardo Sanchez, Zhirui Xu, Werner Lustermann, Liang Sun, Jian Zhao, Ji Hyun Kim, Zheng Wang, Matthias Weber, Xiao Wang

The evolution of the electromagnetic coupling, α, in the momentum-transfer range 1800 GeV2 < -Q2 < 21600 GeV2 is studied with about 40 000 Bhabha-scattering events collected with the L3 detector at LEP at centre-of-mass energies √s = 189-209 GeV. The runni ...

2005