Zobrazeno 1 - 10
of 59
pro vyhledávání: '"Laur Järv"'
Autor:
Sebastián Bahamonde, Laur Järv
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 82, Iss 10, Pp 1-21 (2022)
Abstract In symmetric teleparallel gravities, where the independent connection is characterized by nonmetricity while curvature and torsion are zero, it is possible to find a coordinate system whereby the connection vanishes globally and covariant de
Externí odkaz:
https://doaj.org/article/fccbb4aa9a0e404ebc7964bc64329e65
Autor:
Laur Järv, Piret Kuusk
Publikováno v:
Universe, Vol 10, Iss 1, p 1 (2023)
We consider homogeneous and isotropic cosmological models in the framework of three geometrical theories of gravitation. In Einstein’s general relativity, they are given in terms of the curvature of the Levi-Civita connection in torsion-free metric
Externí odkaz:
https://doaj.org/article/68afb9c28ba349a49daa478e8b9075e1
Autor:
Laur Järv, Alexey Toporensky
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 82, Iss 2, Pp 1-20 (2022)
Abstract We reconsider the dynamical systems approach to analyze inflationary universe in the Jordan frame models of scalar field nonminimally coupled to curvature. The adopted set of variables allows us to clearly distinguish between different asymp
Externí odkaz:
https://doaj.org/article/dc094cfb1c0e481eb294d7c4b586e317
Autor:
Laur Järv, Joosep Lember
Publikováno v:
Universe, Vol 7, Iss 6, p 179 (2021)
We construct global phase portraits of inflationary dynamics in teleparallel gravity models with a scalar field nonminimally coupled to torsion scalar. The adopted set of variables can clearly distinguish between different asymptotic states as fixed
Externí odkaz:
https://doaj.org/article/02d59cb5c3604fe7b1d7866a9305f68c
Publikováno v:
Universe, Vol 5, Iss 6, p 142 (2019)
Teleparallel geometry utilizes Weitzenböck connection which has nontrivial torsion but no curvature and does not directly follow from the metric like Levi−Civita connection. In extended teleparallel theories, for instance in f ( T ) or scalar-tors
Externí odkaz:
https://doaj.org/article/30da8378a575440eb7839dd7ae405674
Autor:
Laur Järv
Publikováno v:
Universe, Vol 3, Iss 2, p 37 (2017)
In theories where a scalar field couples nonminimally to gravity, the effective gravitational “constant” becomes dependent on the value of the scalar field. This note first gives a brief review on how the cosmological evolution provides a dynamic
Externí odkaz:
https://doaj.org/article/9274ffe403534461ac9eddb2ccd1c3ed
Publikováno v:
The Fifteenth Marcel Grossmann Meeting.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5770520c8a7363bb9c7014e3e38ca6f5
https://doi.org/10.1142/9789811258251_0056
https://doi.org/10.1142/9789811258251_0056
Autor:
Alexey Toporensky, Laur Järv
Publikováno v:
European Physical Journal
We reconsider the dynamical systems approach to analyze inflationary universe in the Jordan frame models of scalar field nonminimally coupled to curvature. The adopted set of variables allows us to clearly distinguish between different asymptotic sta
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cc40ae5068a2bcf4dae4f5444b2bf46f
https://doi.org/10.1140/epjc/s10052-022-10124-3
https://doi.org/10.1140/epjc/s10052-022-10124-3
We construct Pleba\'nski-Demia\'nski stationary and axisymmetric solutions with two expanding and double principal null directions in the framework of Metric-Affine gauge theory of gravity. Starting from the new improved form of the metric with vanis
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::65241573a77c17a41538bdad38bfcf83
Publikováno v:
Journal of Cosmology and Astroparticle Physics. 2022:082
Symmetric teleparallel gravity is constructed with a nonzero nonmetricity tensor while both torsion and curvature are vanishing. In this framework, we find exact scalarised spherically symmetric static solutions in scalar-tensor theories built with a
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c46eaa81e4047813f0624e79e959633f
https://doi.org/10.1088/1475-7516/2022/08/082
https://doi.org/10.1088/1475-7516/2022/08/082