Publications associées à Spin connection

Coupling metric-affine gravity to a Higgs-like scalar field

General relativity (GR) exists in different formulations. They are equivalent in pure gravity but generically lead to distinct predictions once matter is included. After a brief overview of various versions of GR, we focus on metric-affine gravity, which a ...

American Physical Society2022

Real space and reciprocal space investigations of the spin dynamics in skyrmion-hosting materials

Le Yu

Magnetic skyrmions are whirl-like spin configurations with particle-like properties protected by non-trivial topology. Due to their unique spin structures and dynamical properties, they have attracted tremendous interests over the past decade, from fundame ...

EPFL2022

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

Dimerization and effective decoupling in two spin-1 generalizations of the spin-1/2 Majumdar-Ghosh chain

Frédéric Mila, Natalia Chepiga

We perform a systematic DMRG investigation of the two natural spin-1 generalizations of the spin-1/2 Majumdar-Ghosh chain, the spin-1 J(1)-J(2) Heisenberg chain, where J(2) is a next-nearest-neighbor Heisenberg coupling, and the spin-1 J(1)-J(3) model, whe ...

2019

Simplification of neural network models

Wulfram Gerstner, Henry Markram, Eilif Benjamin Muller, James Gonzalo King, Idan Segev, Marc-Oliver Gewaltig, Christian Antonio Pozzorini, Willem Anna Mark Wybo, Christian Andreas Rössert, Csaba Erö

The simplification of neural network models is described. For example, a method for simplifying a neural network model includes providing the neural network model to be simplified, defining a first temporal filter for the conveyance of input from a neuron ...

2018

Ising pairing in superconducting NbSe2 atomic layers

László Forró, Helmuth Berger

The properties of two-dimensional transition metal dichalcogenides arising from strong spin-orbit interactions and valley-dependent Berry curvature effects have recently attracted considerable interest(1-7). Although single-particle and excitonic phenomena ...

Nature Publishing Group2016

The particle spectrum of parity-violating Poincare gravitational theory

Georgios Karananas

In this paper we investigate the physical spectrum of the gravitational theory based on the Poincare group with terms that are at most quadratic in tetrad and spin connection, allowing for the presence of parity-even as well as parity-odd invariants. We de ...

Iop Publishing Ltd2015

Homogeneous Sobolev Metric of Order One on Diffeomorphism Groups on Real Line

Martins Bruveris, Martin Bauer

In this article we study Sobolev metrics of order one on diffeomorphism groups on the real line. We prove that the space equipped with the homogeneous Sobolev metric of order one is a flat space in the sense of Riemannian geometry, as it is isometric to an ...

Springer Verlag2014

Experimental testing and simulation of bolted beam-column connections having thick extended endplates and multiple bolts per row

Alain Nussbaumer, Gary Scott Prinz, Luís Costa Borges, Shyam Khadka

Retrofit of existing steel buildings often requires strengthening of the connection regions. One common connection, the bolted beam-column connection, is often strengthened in design using stiffened extended endplates, or with continuity plates welded betw ...

Elsevier2014

The quantum mechanics of perfect fluids

Riccardo Rattazzi, Solomon G Shamsuddin Osman Endlich

We consider the canonical quantization of an ordinary fluid. The resulting long-distance effective field theory is derivatively coupled, and therefore strongly coupled in the UV. The system however exhibits a number of peculiarities, associated with the vo ...

Springer Nature2011