Zobrazeno 1 - 10
of 285
pro vyhledávání: '"Koshelev, A. S."'
We show how infinite derivative modifications of gravity impact on the stochastic background of Gravitational Waves from early Universe. The generic property of the ghost-free theory fixed on Minkowski space-time is the emergence of an infinite numbe
Externí odkaz:
http://arxiv.org/abs/2408.04004
Publikováno v:
Handbook of Quantum Gravity, pp 1-38 (2023), Springer Nature Singapore
In this chapter we review the recent developments of realizing $R^2$-like inflation in the framework of a most general UV nonlocal extension of Einstein's general theory of relativity (GR). It is a well-motivated robust approach towards quantum gravi
Externí odkaz:
http://arxiv.org/abs/2305.18716
Gravity can be embedded into a renormalizable theory by means of adding quadratic in curvature terms. However, this at first leads to the presence of the Weyl ghost. It is possible to get rid of this ghost if the locality assumption is weakened and t
Externí odkaz:
http://arxiv.org/abs/2211.02070
Publikováno v:
JHEP 07 (2023) 094
In [1], a most general higher curvature non-local gravity action was derived that admits a particular $R^2$-like inflationary solution predicting the spectral index of primordial scalar perturbations $n_s(N)\approx 1-\frac{2}{N}$, where $N$ is the nu
Externí odkaz:
http://arxiv.org/abs/2210.16459
Publikováno v:
JHEP 07(2023) 146
The $R^2$ inflation which is an extension of general relativity (GR) by quadratic scalar curvature introduces a quasi-de Sitter expansion of the early Universe governed by Ricci scalar being an eigenmode of d'Alembertian operator. In this paper, we d
Externí odkaz:
http://arxiv.org/abs/2209.02515
Publikováno v:
Phys. Lett. B 841, 137924 (2023)
We show a theorem proving that a non-local bosonic field upon a covariant interaction with a confining gauge field undergoes the confinement of its degrees of freedom present in the free theory changing completely the physical mass spectrum following
Externí odkaz:
http://arxiv.org/abs/2207.06394
Scattering amplitudes mediated by graviton exchange display IR singularities in the forward limit. This obstructs standard application of positivity bounds based on twice subtracted dispersion relations. Such divergences can be cancelled only if the
Externí odkaz:
http://arxiv.org/abs/2205.13332
Publikováno v:
Class. Quantum Grav. 41, 015014 (2024)
We consider a non-Abelian Lee--Wick gauge theory and discuss Becchi-Rouet-Stora-Tyutin (BRST) invariance. It contains fourth-order derivative as extensions of the kinetic term, leading to massive ghosts in the theory upon quantization. We particularl
Externí odkaz:
http://arxiv.org/abs/2202.09578
Autor:
Dementeva, Ekaterina V., Shakirova, Azaliya A., Orekhova, Kseniia N., Popova, Tatiana B., Yagovkina, Maria A., Lihachev, Aleksey I., Dementev, Petr A., Venevtsev, Ivan D., Zatsepin, Anatoliy F., Koshelev, Daniil S., Utochnikova, Valentina V., Burakov, Boris E., Zamoryanskaya, Maria V.
Publikováno v:
In Journal of Alloys and Compounds 5 December 2024 1007
Autor:
Evsiunina, Mariia V., Khult, Enni K., Matveev, Petr I., Kalle, Paulina, Lemport, Pavel S., Petrov, Valentine S., Aksenova, Svetlana A., Nelyubina, Yulia V., Koshelev, Daniil S., Utochnikova, Valentina V., Petrov, Vladimir G., Ustynyuk, Yury A., Nenajdenko, Valentine G.
Publikováno v:
In Separation and Purification Technology 2 July 2024 339