Webinar

Webinar

Fluid dynamical interpretation of the Einstein-Cartan field equations with respect to a generic null hypersurface

Speaker: Sumit Dey and Bibhas Ranjan Majhi (Faculty of Physics, University of Warsaw, Poland)

तिथि और समय
कार्यक्रम का स्थान
SCM Lecture Hall

अमूर्त

In the present work, we study the dynamics of a general null hypersurface in the Einstein Cartan (EC) theory generated by a null vector field 𝑙 α . We see that under a particular relation between the torsion tensor and the null generators called the geodesic constraint, the dynamical evolution of the Hajicek one-form is governed by the component 𝐺^ ab 𝑙 α qb c,  𝐺^ ab 𝑙 α qb c, where 𝑞 is the induced metric on an orthogonal spacelike cross-section of the null surface and 𝐺^ ab is the analogue of the Einstein tensor in spacetime with intrinsic torsion. Using the gravitational field equations for the EC theory, we see that above mentioned evolution equations can be provided a fluid-dynamical interpretation respectively. The relevant thermodynamic and fluid parameters have been properly identified. The dynamics of the Hajicek one-form has been studied in a local inertial frame and its correspondence with Cosserat fluid has been established.