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We consider quantum effects of a massive antisymmetric tensor field on the dynamics of de Sitter space-time. Our starting point is the most general, stable, linearized Lagrangian arising in nonsymmetric gravitational theories (NGTs), where…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Tomas Janssen , Tomislav Prokopec

We employ the graviton self-energy induced by a massless, minimally coupled (MMC) scalar on de Sitter background to compute the quantum corrections to the gravitational potentials of a static point particle with a mass $M$. The…

General Relativity and Quantum Cosmology · Physics 2016-02-17 Sohyun Park , Tomislav Prokopec , R. P. Woodard

In this paper a framework is introduced to remove the huge discrepancy between the empirical value of the cosmological constant and the contribution to the cosmological constant predicted from the vacuum energy of quantum fields. An extra…

High Energy Physics - Theory · Physics 2008-11-26 Recai Erdem

For the electromagnetic field in (D+1)-dimensional locally de Sitter (dS) spacetime, we analyze the effects of a generalized cosmic string type defect on the vacuum expectation value of the energy-momentum tensor. For the Bunch-Davies…

High Energy Physics - Theory · Physics 2023-06-21 A. A. Saharian , V. F. Manukyan , V. Kh. Kotanjyan , A. A. Grigoryan

An improved method is given for the computation of the stress-energy tensor of a quantized scalar field using adiabatic regularization. The method works for fields with arbitrary mass and curvature coupling in Robertson-Walker spacetimes…

General Relativity and Quantum Cosmology · Physics 2016-08-25 Paul R. Anderson , Wayne Eaker

We present the details for the covariant renormalization of the stress tensor for vacuum tensor perturbations at the level of the effective action, adopting Hadamard regularization techniques to isolate short distance divergences and gauge…

High Energy Physics - Theory · Physics 2024-03-26 Anna Negro , Subodh P. Patil

We present a rigorous, regularization independent local quantum field theoretic treatment of the Casimir effect for a quantum scalar field of mass $\mu\ne0$ which yields closed form expressions for the energy density and pressure. As an…

General Relativity and Quantum Cosmology · Physics 2015-05-13 G. Gazzola , M. C. Nemes , W. F. Wreszinski

I argue that a solution to the cosmological constant problem is to assume that the expectation value of the quantum vacuum stress-energy tensor is proportional to the metric tensor with a negative energy density and positive pressure. This…

General Physics · Physics 2018-05-09 Emilio Santos

We calculate quantum loop corrections to the stress-energy flux caused by moving mirrors. We consider massless, self-interacting, $\phi^4$, real scalar theory. In these calculations we encounter a new and quite unexpected subtleties due to…

High Energy Physics - Theory · Physics 2017-09-13 E. T. Akhmedov , S. O. Alexeev

The Euclidean or Bunch-Davies O(4,1) invariant 'vacuum' state of quantum fields in global de Sitter space is shown to be unstable to small perturbations, even for a massive free field with no self-interactions. There are perturbations of…

General Relativity and Quantum Cosmology · Physics 2014-05-28 Paul R. Anderson , Emil Mottola

The canonical quantization of macroscopic electromagnetism was recently presented in New J. Phys. 12 (2010) 123008. This theory is here used to derive the Casimir effect, by considering the special case of thermal and zero-point fields. The…

Quantum Physics · Physics 2015-05-27 T. G. Philbin

We study the consequences due to time varying $G$ and $\Lambda$ in scalar-tensor theories of gravity for cosmology, inspired by the modifications introduced by the Renormalization Group (RG) equations in the Quantum Einstein Gravity. We…

Astrophysics · Physics 2009-11-10 Claudio Rubano , Paolo Scudellaro

The paper considers the general case of incompressible non-classical elasticity with small deformations and rotations. The thermodynamic stability is analysed for free energy density with three rotational degrees of freedom. Although the…

Condensed Matter · Physics 2016-11-25 A. I. Leonov , V. S. Volkov

In the framework of finite temperature conformal scalar field theory on de Sitter space-time the linearized Einstein equations for the renormalized stress tensor are exactly solved. In this theory quantum field fluctuations are concentrated…

General Relativity and Quantum Cosmology · Physics 2010-04-06 D. V. Fursaev , G. Miele

We study perturbative renormalization of the composite operators in the $T\bar T$-deformed two-dimensional free field theories. The pattern of renormalization for the stress-energy tensor is different in the massive and massless cases.…

High Energy Physics - Theory · Physics 2021-06-07 Anshuman Dey , Mikhail Goykhman , Michael Smolkin

First, the present work is concerned with generalising constructions and results in quantum field theory on curved spacetimes from the well-known case of the Klein-Gordon field to Dirac fields. To this end, the enlarged algebra of…

General Relativity and Quantum Cosmology · Physics 2010-10-22 Thomas-Paul Hack

It has been proposed recently to consider in the framework of cosmology an extension of the semiclassical Einstein's equations in which the Einstein tensor is considered as a random function. This paradigm yields a hierarchy of equations…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Claudio Dappiaggi , Alberto Melati

We consider the introduction of anisotropy in a class of bouncing models of cosmology. The presence of anisotropy often spells doom on bouncing models, since the energy density due to the anisotropic stress outweighs that of other matter…

General Relativity and Quantum Cosmology · Physics 2022-01-27 Karthik Rajeev , Vikramaditya Mondal , Sumanta Chakraborty

Quantum vacuum energy has been known to have observable consequences since 1948 when Casimir calculated the force of attraction between parallel uncharged plates, a phenomenon confirmed experimentally with ever increasing precision. Casimir…

High Energy Physics - Theory · Physics 2009-11-07 Kimball A. Milton

The two-point function characterizing the stress tensor fluctuations of a massless minimally coupled field for an invariant vacuum state in de Sitter spacetime is discussed. This two-point function is explicitly computed for spacelike…

General Relativity and Quantum Cosmology · Physics 2011-04-15 Albert Roura , Enric Verdaguer