Zobrazeno 1 - 10
of 48
pro vyhledávání: '"Vardanyan, Tereza"'
Publikováno v:
Eur. Phys. J. C 82 (2022) no.4, 345
We examine long-wavelength correlation functions of massive scalar fields in de Sitter spacetime. For the theory with a quartic self-interaction, the two-point function is calculated up to two loops. Comparing our results with the Hartree-Fock approx
Externí odkaz:
http://arxiv.org/abs/2109.05625
Publikováno v:
Universe 7, 219 (2021)
We analyze the issue of dynamical evolution and time in quantum cosmology. We emphasize the problem of choice of phase space variables that can play the role of a time parameter in such a way that for expectation values of quantum operators the class
Externí odkaz:
http://arxiv.org/abs/2107.00917
Publikováno v:
Phys. Rev. D 102, 065010 (2020)
We develop a method for treating a series of secularly growing terms obtained from quantum perturbative calculations: autonomous first-order differential equations are constructed such that they reproduce this series to the given order. The exact sol
Externí odkaz:
http://arxiv.org/abs/2005.02504
Publikováno v:
JETP Letters 111 (2020) no 6, 306-310
We study the solutions of the Einstein equations in the presence of a thick infinite slab with constant energy density. When there is an isotropy in the plane of the slab, we find an explicit exact solution that matches with the Rindler and Weyl-Levi
Externí odkaz:
http://arxiv.org/abs/2002.12916
We study a mechanism for the amplification of the inflationary scalar perturbation when the inflaton field action is non-canonical, i.e. the inflaton kinetic term has a non-standard form. For such a case the speed of sound of the perturbations genera
Externí odkaz:
http://arxiv.org/abs/1812.02547
Publikováno v:
Physics Letters B 792 (2019 430-435
We find exact static solutions of the Einstein equations in the spacetime with plane symmetry, where an infinite slab with finite thickness and homogeneous energy (mass) density is present. In the first solution the pressure is isotropic, while in th
Externí odkaz:
http://arxiv.org/abs/1811.09493
Autor:
Kamenshchik, Alexander Yu., Pozdeeva, Ekaterina O., Starobinsky, Alexei A., Tronconi, Alessandro, Vardanyan, Tereza, Venturi, Giovanni, Vernov, Sergey Yu.
Publikováno v:
Phys. Rev. D 98, 124028 (2018)
We study static spherically and hyperbolically symmetric solutions of the Einstein equations in the presence of a conformally coupled scalar field and compare them with those in the space filled with a minimally coupled scalar field. We then study th
Externí odkaz:
http://arxiv.org/abs/1811.08213
Publikováno v:
International Journal of Modern Physics D Vol. 28, No. 6 (2019) 1950073
We compare two different approaches to the treatment of the Wheeler-DeWitt equation and the introduction of time in quantum cosmology. One approach is based on the gauge-fixing procedure in theories with first-class constraints, while the other uses
Externí odkaz:
http://arxiv.org/abs/1809.08083
Publikováno v:
Physics Letters B 782 (2018) 55-60
We check the cancellation of the vacuum energy in the Wess-Zumino model at the two-loop order in the component field formalisms with and without auxiliary fields. We show that in both cases the vacuum energy is equal to zero. However, in the formalis
Externí odkaz:
http://arxiv.org/abs/1804.03394
We derive the stochastic description of a massless, interacting scalar field in de Sitter space directly from the quantum theory. This is done by showing that the density matrix for the effective theory of the long wavelength fluctuations of the fiel
Externí odkaz:
http://arxiv.org/abs/1706.07805