Concept

Lagrangien (théorie des champs)

Publications associées (134)

Phonon origin and lattice evolution in charge density wave states

Metallic transition metal dichalcogenides, such as tantalum diselenide (TaSe2), display quantum correlated phenomena of superconductivity and charge density waves (CDWs) at low temperatures. Here, the photophysics of 2H-TaSe2 during CDW transitions is reve ...

AMER PHYSICAL SOC2019

Large effect of metal substrate on magnetic anisotropy of Co on hexagonal boron nitride

Harald Brune, Stefano Rusponi, Christian Wäckerlin, Jan Gui-Hyon Dreiser, Fabio Donati, Aparajita Singha, Romana Baltic

We combine x-ray absorption spectroscopy (XAS), x-raymagnetic circular dichroism (XMCD) and x-ray magnetic linear dichroism (XMLD) data with first principles density functional theory (DFT) calculations and amultiorbital many-body Hamiltonian approach to u ...

IOP PUBLISHING LTD2019

Tits Buildings And K-Stability

Giulio Codogni

A polarized variety is K-stable if, for any test configuration, the Donaldson-Futaki invariant is positive. In this paper, inspired by classical geometric invariant theory, we describe the space of test configurations as a limit of a direct system of Tits ...

CAMBRIDGE UNIV PRESS2019

What do gravitons say about (unimodular) gravity?

Mario Herrero Valea

We revisit the problem of constraining the weak field limit of the gravitational lagrangian from S-matrix properties. From unitarity and Lorentz invariance of the S-matrix of massless gravitons, we derive on-shell gauge invariance to consist on the transve ...

SPRINGER2018

Quasi-elastic neutrino reactions on carbon and lead nuclei

Soheyl Massoudi

We examine neutral-current quasi-elastic neutrino-nucleus reactions on C-12 and Pb-208 targets. We use the relativistic mean field theory approach to describe the nuclear dynamics. We compute the cross sections for the scattering of 150, 500 and 1000 MeV n ...

Iop Publishing Ltd2018

R-current three-point functions in 4d N=1 superconformal theories

Andrea Manenti, Alessandro Vichi

In 4d N = 1 superconformal field theories (SCFTs) the R-symmetry current, the stress-energy tensor, and the supersymmetry currents are grouped into a single object, the Ferrara-Zumino multiplet. In this work we study the most general form of three-point fu ...

SPRINGER2018

Laser-Induced Skyrmion Writing and Erasing in an Ultrafast Cryo-Lorentz Transmission Electron Microscope

Henrik Moodysson Rønnow, Fabrizio Carbone, Giovanni Maria Vanacore, Ivan Madan, Enrico Pomarico, Gabriele Berruto, Ping Huang, Yoshie Murooka

We demonstrate that light-induced heat pulses of different duration and energy can write Skyrmions in a broad range of temperatures and magnetic field in FeGe. Using a combination of camera-rate and pump- probe cryo-Lorentz transmission electron microscopy ...

2018

Optimal Lagrange Multipliers for Dependent Rate Allocation in Video Coding

Pascal Frossard, Ana Karina De Abreu Goes

In a typical video rate allocation problem, the objective is to optimally distribute a source rate budget among a set of (in)dependently coded data units to minimize the total distortion. Conventional Lagrangian approaches convert the lone rate constraint ...

Elsevier2018

Tracking and Analysis of Skyrmion Motion with matlab

This TP IV follows the TP IV "Tracking of Skyrmion Motion with matlab" and is using new movie as material. This report presents a description of a code, including an identification and a tracking code, based on new motion hypotheses resulting from the prev ...

2018

On the Lagrangian structure of transport equations: The Vlasov–Poisson system

Maria Colombo

The Vlasov-Poisson system is an important nonlinear transport equation, used to describe the evolution of particles under their self-consistent electric or gravitational field. The existence of classical solutions is limited to dimensions d

2017

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