Concept

Lagrangien (théorie des champs)

Publications associées (134)

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Noether Theorems and Quantum Anomalies

Tudor Ratiu

A quantum anomaly is the breaking of symmetry with respect to some transformations after the quantization of a classical Hamiltonian or Lagrangian system. It is shown that both the Noether theorems (including their infinite-dimensional versions) and the ex ...

Springer Verlag2017

Cross-code gyrokinetic verification and benchmark on the linear collisionless dynamics of the geodesic acoustic mode

Alberto Bottino, Gabriele Merlo

The linear properties of the geodesic acoustic modes (GAMs) in tokamaks are investigated by means of the comparison of analytical theory and gyrokinetic numerical simulations. The dependence on the value of the safety factor, finite-orbit-width of the ions ...

Amer Inst Physics2017

Verification of Gyrokinetic codes: Theoretical background and applications

Laurent Villard, Alberto Bottino

In fusion plasmas, the strong magnetic field allows the fast gyro-motion to be systematically removed from the description of the dynamics, resulting in a considerable model simplification and gain of computational time. Nowadays, the gyrokinetic (GK) code ...

Amer Inst Physics2017

Entropy and optimality in river deltas

Andrea Rinaldo

The form and function of river deltas is intricately linked to the evolving structure of their channel networks, which controls how effectively deltas are nourished with sediments and nutrients.Understanding the coevolution of deltaic channels and their fl ...

Natl Acad Sciences2017

Magnetic Skyrmions and Skyrmion Clusters in the Helical Phase of Cu2OSeO3

Henrik Moodysson Rønnow, Fabrizio Carbone, Ping Huang, Yoshie Murooka

Skyrmions are nanometric spin whirls that can be stabilized in magnets lacking inversion symmetry. The properties of isolated Skyrmions embedded in a ferromagnetic background have been intensively studied. We show that single Skyrmions and clusters of Skyr ...

2017

On a Lagrangian Formulation of the Incompressible Euler Equation

Hasan Inci

In this paper we show that the incompressible Euler equation on the Sobolev space H-s(R-n), s> n/2+1, can be expressed in Lagrangian coordinates as a geodesic equation on an infinite dimensional manifold. Moreover the Christoffel map describing the geodesi ...

Global Science Press2016

Supergravity with broken Lorentz invariance

Sergey Sibiryakov

The supersymmetric extension of the Lorentz violating Einstein-aether theory of gravity is considered. The most general Lagrangian of the linearized Einstein-aether supergravity is constructed using the superfield formalism. The constraints imposed by supe ...

EDP Sciences2016

Single-Layered Hittorf's Phosphorus: A Wide-Bandgap High Mobility 2D Material

Martin Uhrin, Georg Schusteritsch

We propose here a two-dimensional material based on a single layer of violet or Hittorf's phosphorus. Using first principles density functional theory, we find it to be energetically very stable, comparable to other previously proposed single layered phosp ...

Amer Chemical Soc2016

Confined vortices in topologically massive U(1) x U(1) theory

Yannis Burnier, Eray Sabancilar

We report on a new topological vortex solution in U(1) x U(1) Maxwell-Chern-Simons theory. The existence of the vortex is envisaged by analytical means, and a numerical solution is obtained by integrating the equations of motion. These vortices have a long ...

Amer Physical Soc2015

Renormalized solutions to the continuity equation with an integrable damping term

Maria Colombo

We consider the continuity equation with a nonsmooth vector field and a damping term. In their fundamental paper, DiPerna and Lions (Invent Math 98:511-547, 1989) proved that, when the damping term is bounded in space and time, the equation is well posed i ...

2015