Casimir densities for a conducting plate in de Sitter spacetime

2nd International Symposium on the Modern Physics of Compact Stars and Relativistic Gravity

物理学;天文学

Kotanjyan, A.S.^1 ; Saharian, A.A.^1 ; Nersisyan, H.A.^1

Department of Physics, Yerevan State University, 1 Alex Manoogian Street, 0025 Yerevan, Armenia^1

关键词: Conducting plates;    Conformal invariance;    Energy-momentum tensor;    Expectation values;    Off-diagonal components;    Space-time coordinates;    Spatial dimension;    Two-point function;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/496/1/012027/pdf
DOI  :  10.1088/1742-6596/496/1/012027

学科分类：天文学(综合)

来源: IOP

【 摘 要 】

Two-point functions for the electromagnetic field in background of (D + 1)-dimensional dS spacetime are evaluated assuming that the field is prepared in the Bunch-Davies vacuum state. By using these functions, the vacuum expectation values (VEVs) of the field squared and the energy-momentum tensor are investigated in the geometry of a conducting plate. The VEVs are explicitly decomposed into the boundary-free and plate-induced parts. For points outside of the plate the renormalization is needed for the first parts only. Because of the maximal symmetry of the background spacetime and of the Bunch-Davies vacuum state, the boundary-free parts do not depend on spacetime coordinates, whereas the plate-induced parts are functions of the proper distance of the observation point from the plate. The plate-induced part in the VEV of the energy-momentum tensor vanishes for D 3 which is a direct consequence of a conformal invariance of the electromagnetic field for this spatial dimension. For D > 3, in addition to the diagonal components, the vacuum energy-momentum tensor has nonzero off-diagonal component which describes energy flux along the direction normal to the plate.