Version imprimable

Ressource documentaire

Thomas Backdahl - Symmetry operators, conserved currents and energy momentum tensors (en Anglais)


URL d'accès : http://www.canal-u.tv/?redirectVideo=22569...

Droits : CC BY-NC-ND 4.0

Auteur(s) : Backdahl Thomas, Bastien Fanny
04-07-2014

Description : Conserved quantities, for example energy and momentum, play a fundamental role in the analysis of dynamics of particles and fields. For field equations, one manifestation of conserved quantities in a broad sense is the existence of symmetry operators, i.e. linear differential operators which take solutions to solutions. A well known example of a symmetry operator for the scalar wave equation is provided by the Lie derivative along a Killing vector field. It is important to note that other kinds of objects can generate symmetry operators. For waves in the Kerr spacetime there is a symmetry operator associated with Carter's constant. This symmetry, which is "hidden" in the sense that it arises from a Killing spinor, satisfying a generalization of the Killing vector equation, rather than a Killing vector, was an essential ingredient in a proof of decay of scalar waves on the Kerr background by Andersson and Blue. In this talk we will consider what conditions on a spacetime are necessary for existence of symmetry operators for the conformal wave equation, the Dirac Weyl equation, and the Maxwell equation, i.e. for massless test fields of spins 0, 1/2 and 1. We will investigate how the conditions for the symmetry operators for the different field equations are related, and how they are related to existence of conserved currents. Furthermore, these tools lead to the construction of a new energy momentum tensor for a Maxwell field on a Kerr background. This will provide a powerful tool for the study of decay of Maxwell fields on the Kerr spacetime.
Mots-clés libres : mathématiques,Grenoble,école d'été,General Relativity,institut fourier,summer school,asymptotic analysis
TECHNIQUE

Type : image en mouvement
Format : video/x-flv


Source(s) : 
rtmpt://fms2.cerimes.fr:80/vod/institut_fourier/thomas.backdahl.symmetry.operators.conserved.currents.and.energy.momentum.tensors_22569/backdhal_ecoleete_04072014_sd.mp4


Entrepôt d'origine : Canal-u.fr
Identifiant : oai:canal-u.fr:22569
Type de ressource : Ressource documentaire
Exporter au format XML

Ressource pédagogique

Thomas Backdahl - Symmetry operators, conserved currents and energy momentum tensors (en Anglais)


URL d'accès : http://www.canal-u.tv/video/institut_fourier/thoma...
rtmpt://fms2.cerimes.fr:80/vod/institut_fourier/th...

Identifiant de la fiche : 22569
Schéma de la métadonnée : LOMv1.0, LOMFRv1.0

Droits : libre de droits, gratuit
Droits réservés à l'éditeur et aux auteurs. CC BY-NC-ND 4.0

Auteur(s) : BACKDAHL THOMAS
Éditeur(s) : Fanny Bastien
04-07-2014

Description : Conserved quantities, for example energy and momentum, play a fundamental role in the analysis of dynamics of particles and fields. For field equations, one manifestation of conserved quantities in a broad sense is the existence of symmetry operators, i.e. linear differential operators which take solutions to solutions. A well known example of a symmetry operator for the scalar wave equation is provided by the Lie derivative along a Killing vector field. It is important to note that other kinds of objects can generate symmetry operators. For waves in the Kerr spacetime there is a symmetry operator associated with Carter's constant. This symmetry, which is "hidden" in the sense that it arises from a Killing spinor, satisfying a generalization of the Killing vector equation, rather than a Killing vector, was an essential ingredient in a proof of decay of scalar waves on the Kerr background by Andersson and Blue. In this talk we will consider what conditions on a spacetime are necessary for existence of symmetry operators for the conformal wave equation, the Dirac Weyl equation, and the Maxwell equation, i.e. for massless test fields of spins 0, 1/2 and 1. We will investigate how the conditions for the symmetry operators for the different field equations are related, and how they are related to existence of conserved currents. Furthermore, these tools lead to the construction of a new energy momentum tensor for a Maxwell field on a Kerr background. This will provide a powerful tool for the study of decay of Maxwell fields on the Kerr spacetime.
Mots-clés libres : mathématiques, Grenoble, école d'été, General Relativity, institut fourier, summer school, asymptotic analysis

Classification UNIT : Mathématiques > Fondamentaux
Classification : Mathématiques et Sciences de la nature et de la matière > Mathématiques
Indice(s) Dewey: Mathématiques (510)


PEDAGOGIQUE

Type pédagogique : cours / présentation

Niveau : doctorat



TECHNIQUE


Type de contenu : image en mouvement
Format : video/x-flv
Taille : 1.61 Go
Durée d'exécution : 44 minutes 19 secondes



RELATIONS


Cette ressource fait partie de :
  • Ecoles d'été
  • 2014



Entrepôt d'origine : Canal-u.fr
Identifiant : oai:canal-u.fr:22569
Type de ressource : Ressource pédagogique
Exporter au format XML