English
Related papers

Related papers: Wightman function and vacuum densities in de Sitte…

200 papers

Wightman function and vacuum expectation value of the field square are evaluated for a massive scalar field with general curvature coupling parameter subject to Robin boundary conditions on two codimension one parallel branes located on…

High Energy Physics - Theory · Physics 2009-11-11 Aram A. Saharian

We construct the Wightman function for symmetric traceless tensors and Dirac fermions in dS$_{d+1}$ in a coordinate and index free formalism using a $d+2$ dimensional ambient space. We expand the embedding space formalism to cover spinor…

High Energy Physics - Theory · Physics 2022-12-16 Ben Pethybridge , Vladimir Schaub

In this paper we investigate the vacuum polarization effects associated with a massive quantum scalar field in de Sitter spacetime in the presence of gravitational topological defects. Specifically we calculate the vacuum expectation value…

High Energy Physics - Theory · Physics 2015-05-18 E. R. Bezerra de Mello

The vacuum expectation value of the energy-momentum tensor and the Casimir forces are investigated for a massive scalar field with an arbitrary curvature coupling parameter in the geometry of two parallel plates, on the background of de…

High Energy Physics - Theory · Physics 2011-12-01 A. A. Saharian

We consider warped compactifications in (4+d)-dimensional theories, with four dimensional de Sitter dS_4 vacua (with Hubble parameter H) and with a compact internal space. After introducing a gauge-invariant formalism for the generic metric…

High Energy Physics - Theory · Physics 2010-11-19 Carlo Contaldi , Lev Kofman , Marco Peloso

The vacuum expectation value of the current density for a charged scalar field is investigated in Rindler spacetime with a part of spatial dimensions compactified to a torus. It is assumed that the field is prepared in the Fulling-Rindler…

High Energy Physics - Theory · Physics 2022-05-27 V. Kh. Kotanjyan , A. A. Saharian , M. R. Setare

The main objective of this paper is to analyze the vacuum expectation value (VEV) of the energy-momentum tensor (EMT) associated with a charged scalar quantum field in a high-dimensional cosmic string spacetime admitting the presence of a…

High Energy Physics - Theory · Physics 2019-08-26 E. A. F. Bragança , H. F. Santana Mota , E. R. Bezerra de Mello

We evaluate the Wightman function, the mean field squared and the vacuum expectation value (VEV) of the energy-momentum tensor for a scalar field with Robin boundary condition on a spherical shell in the background of a constant negative…

High Energy Physics - Theory · Physics 2014-09-29 S. Bellucci , A. A. Saharian , N. A. Saharyan

We investigate the vacuum expectation values for the energy-momentum tensor of a massive scalar field with general curvature coupling and obeying the Robin boundary condition on a spherical shell in the $D+1$-dimensional global monopole…

High Energy Physics - Theory · Physics 2009-11-10 A. A. Saharian , M. R. Setare

We investigate the Hadamard function and the vacuum expectation value of the current density for a charged massive scalar field on a slice of anti-de Sitter (AdS) space described in Poincar\'{e} coordinates with toroidally compact…

High Energy Physics - Theory · Physics 2014-12-31 E. R. Bezerra de Mello , A. A. Saharian , V. Vardanyan

In this paper we investigate the vacuum densities for a massive scalar field with general curvature coupling in background of a (2+1)-dimensional spacetime corresponding to a cylindrical tube with a hemispherical cap. A complete set of mode…

General Relativity and Quantum Cosmology · Physics 2016-01-19 E. R. Bezerra de Mello , A. A. Saharian

The electromagnetic field correlators are evaluated around a cosmic string in background of $(D+1)$-dimensional dS spacetime assuming that the field is prepared in the Bunch-Davies vacuum state. The correlators are presented in the…

High Energy Physics - Theory · Physics 2017-08-01 A. A. Saharian , V. F. Manukyan , N. A. Saharyan

We present a covariant quantization scheme for the so-called "partially massless" graviton field in de Sitter spacetime. Our approach is founded on the principles of the de Sitter group representation theory (in the sense given by Wigner),…

General Relativity and Quantum Cosmology · Physics 2023-09-25 Jean-Pierre Gazeau , Hamed Pejhan

We investigate topological effects of a cosmic string and compactification of a spatial dimension on the vacuum expectation value (VEV) of the energy-momentum tensor for a fermionic field in (4+1)-dimensional locally AdS spacetime. The…

High Energy Physics - Theory · Physics 2022-01-12 S. Bellucci , W. Oliveira dos Santos , E. R. Bezerra de Mello , A. A. Saharian

We study the possibility that the vacuum energy density of scalar and internal-space gauge fields arising from the process of dimensional reduction of higher dimensional gravity theories plays the role of quintessence. We show that, for the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 M. C. Bento , O. Bertolami

We investigate the Wightman function, the vacuum expectation values of the field squared and the energy-momentum tensor for a massive scalar field with general curvature coupling parameter subject to Robin boundary conditions on two…

High Energy Physics - Theory · Physics 2009-05-06 A. A. Saharian

A covariant quantization of the free spinor fields (s=1/2) in 4-dimensional de Sitter (dS) space-time based on analyticity in the complexified pseudo-Riemanian manifold is presented. We define the Wigthman two-point function ${\cal…

General Relativity and Quantum Cosmology · Physics 2016-08-31 M. V. Takook

We explore aspects of the physics of de Sitter (dS) space that are relevant to holography with a positive cosmological constant. First we display a nonlocal map that commutes with the de Sitter isometries, transforms the bulk-boundary…

High Energy Physics - Theory · Physics 2009-03-16 Vijay Balasubramanian , Jan de Boer , Djordje Minic

We investigate the fermionic condensate and the vacuum expectation value of the energy-momentum tensor for a massive spinor field in the geometry of a straight cosmic string on background of de Sitter spacetime. By using the Abel-Plana…

High Energy Physics - Theory · Physics 2010-08-24 E. R. Bezerra de Mello , A. A. Saharian

(1+1)-dimensional locally de Sitter Friedmann-Robertson-Walker cosmologies with compact spatial sections allow cosh, sinh and exponential evolution laws, each with a freely-specifiable spatial circumference parameter, and the value of this…

General Relativity and Quantum Cosmology · Physics 2024-01-19 Vladimir Toussaint , Jorma Louko