Zobrazeno 1 - 10
of 2 665
pro vyhledávání: '"P. Rasanen"'
Autor:
Hassan, Ali, Rasanen, Syksy
We consider the Chern-Simons term coupled to the inflaton in the Palatini formulation of general relativity. In contrast to the metric formulation, here the Chern-Simons term affects also the background evolution. We approximately solve for the conne
Externí odkaz:
http://arxiv.org/abs/2408.14983
Publikováno v:
Phys. Rev. Lett. 133, 121403 (2024)
We study the formation of primordial black holes (PBH) with ultra-slow-roll inflation when stochastic effects are important. We use the $\Delta N$ formalism and simplify the stochastic equations with an analytical constant-roll approximation. Conside
Externí odkaz:
http://arxiv.org/abs/2312.12911
Autor:
Nezhad, Hamed Bouzari, Rasanen, Syksy
Publikováno v:
JCAP02(2024)009
We study models where a scalar field has derivative and non-derivative couplings to the Ricci tensor and the co-Ricci tensor with a view to inflation. We consider both the metric formulation and the Palatini formulation. In the Palatini case, the cou
Externí odkaz:
http://arxiv.org/abs/2307.04618
Autor:
Annala, Jaakko, Rasanen, Syksy
Publikováno v:
JCAP04(2023)014 [Erratum: JCAP08(2023)E02]
We study the stability of theories where the gravitational action has arbitrary algebraic dependence on the three first traces of the Riemann tensor: the Ricci tensor, the co-Ricci tensor, and the homothetic curvature tensor. We collectively call the
Externí odkaz:
http://arxiv.org/abs/2212.09820
Autor:
Rasanen, Syksy, Verbin, Yosef
Publikováno v:
Open Journal of Astophysics, Vol. 6, 2023, January 26, 2023 IST
We consider a formulation of gauge field theory where the gauge field $A_\alpha$ and the field strength $F_{\alpha\beta}$ are independent variables, as in the Palatini formulation of gravity. For the simplest gauge field action, this is known to be e
Externí odkaz:
http://arxiv.org/abs/2211.15584
Autor:
Noam Gavriely, Jukka O Rasanen, Sharon Abadi Saar, Lionel Lamhaut, Alice Hutin, Fanny Lidouren, Yara Abi Zeid Daou, Renaud Tissier
Publikováno v:
Resuscitation Plus, Vol 19, Iss , Pp 100681- (2024)
Objectives: The cognitive outcome of CPR is poor. This study aims to evaluate if enhancing blood flow to the brain and oxygen dissociation from the hemoglobin improve cerebral O2 transport during CPR in cardiac arrest swine. Methods: Standard swine-C
Externí odkaz:
https://doaj.org/article/19aa020287fc4b3a9958e729fa9e707d
Implications of stochastic effects for primordial black hole production in ultra-slow-roll inflation
Publikováno v:
JCAP05(2022)027
We study the impact of stochastic noise on the generation of primordial black hole (PBH) seeds in ultra-slow-roll (USR) inflation with numerical simulations. We consider the non-linearity of the system by consistently taking into account the noise de
Externí odkaz:
http://arxiv.org/abs/2111.07437
Publikováno v:
JHEP06(2022)164
We calculate the tree-level amplitudes for electrically neutral $2\to2$ scattering for the Standard Model Higgs doublet non-minimally coupled to the Ricci scalar. We consider both the metric and the Palatini formulation of gravity. We find the partia
Externí odkaz:
http://arxiv.org/abs/2111.05621
Autor:
Koksbang, Sofie Marie, Rasanen, Syksy
Publikováno v:
JCAP04(2022)030
Light propagation in cosmology is usually studied in the geometrical optics approximation which requires the spacetime curvature to be much smaller than the light wavenumber. However, for non-fuzzy particle dark matter the curvature is concentrated i
Externí odkaz:
http://arxiv.org/abs/2108.06163
Autor:
Annala, Jaakko, Rasanen, Syksy
Publikováno v:
JCAP09(2021)032
We study inflation with the most general non-degenerate gravitational action that depends on the symmetric part of the Ricci tensor coupled to a scalar field in the Palatini formulation of gravity. We use field redefinitions to shift the effect of th
Externí odkaz:
http://arxiv.org/abs/2106.12422