Zobrazeno 1 - 10
of 320
pro vyhledávání: '"Starobinsky, Alexei"'
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
Post-inflationary evolution and (re)heating of the viable inflationary model, the $R^2$ one, is made more realistic by including the leptogenesis scenario into it. For this purpose, right-handed Majorana neutrinos with a large mass are added to the m
Externí odkaz:
http://arxiv.org/abs/2305.14273
Autor:
Calderón, Rodrigo, L'Huillier, Benjamin, Polarski, David, Shafieloo, Arman, Starobinsky, Alexei A.
Based on a formalism introduced in our previous work, we reconstruct the phenomenological function $G_{\rm eff}(z)$ describing deviations from General Relativity (GR) in a model-independent manner. In this alternative approach, we model $\mu\equiv G_
Externí odkaz:
http://arxiv.org/abs/2301.00640
The $Om3$ diagnostic (Shafieloo et al. 2012) tests the consistency of the cosmological constant as a candidate for dark energy using Baryon Acoustic Oscillation (BAO) data. An important feature of $Om3$ is that it is independent of any parametric ass
Externí odkaz:
http://arxiv.org/abs/2211.03344
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:
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
Autor:
Hazra, Dhiraj Kumar, Paoletti, Daniela, Debono, Ivan, Shafieloo, Arman, Smoot, George F., Starobinsky, Alexei A.
Publikováno v:
JCAP12(2021)038
We present constraints on inflationary dynamics and features in the primordial power spectrum of scalar perturbations using the Cosmic Microwave Background temperature, polarization data from Planck 2018 data release and updated likelihoods. We const
Externí odkaz:
http://arxiv.org/abs/2107.09460
Autor:
Galeev, Rafkat, Muharlyamov, Ruslan, Starobinsky, Alexei A., Sushkov, Sergey V., Volkov, Mikhail S.
Publikováno v:
Phys. Rev. D 103, 104015 (2021)
It was found recently that the anisotropies in the homogeneous Bianchi I cosmology considered within the context of a specific Horndeski theory are damped near the initial singularity instead of being amplified. In this work we extend the analysis of
Externí odkaz:
http://arxiv.org/abs/2102.10981