Zobrazeno 1 - 10
of 5 464
pro vyhledávání: '"curvature: perturbation"'
We propose a unified framework that describes both the curvaton mechanism for generating primordial density fluctuations and the Affleck-Dine (AD) field for baryogenesis. By introducing a complex scalar field (AD field) carrying a baryon/lepton numbe
Externí odkaz:
http://arxiv.org/abs/2410.07694
Publikováno v:
JCAP 07 (2024) 076
We investigate a model of $R^2$-gravity with a non-minimally coupled scalar field that gives rise to two-stage inflation with a break, that is, with an intermediate stage where inflation momentarily halts. We find that the power spectrum of the primo
Externí odkaz:
http://arxiv.org/abs/2404.02492
Autor:
Zhao, Ji-Xiang, Li, Nan
Publikováno v:
published in Eur. Phys. J. C 84, 222 (2024)
Cosmic inflation can enter an ultraslow-roll (USR) stage, if there is a plateau on the inflaton potential. During this stage, the primordial curvature perturbation ${\mathcal R}_k$ and its power spectrum ${\mathcal P}_{\mathcal R}$ can be remarkably
Externí odkaz:
http://arxiv.org/abs/2403.01416
Cosmological observations, e.g., cosmic microwave background, have precisely measured the spectrum of primordial curvature perturbation on larger scales, but smaller scales are still poorly constrained. Since primordial black holes (PBHs) could form
Externí odkaz:
http://arxiv.org/abs/2311.15848
Publikováno v:
JCAP 05 (2024) 082
The scalar-induced gravitational waves (SIGW), arising from large amplitude primordial density fluctuations, provide a unique observational test for directly probing the epoch of inflation. In this work, we provide constraints on the SIGW background
Externí odkaz:
http://arxiv.org/abs/2311.05423
Publikováno v:
Phys. Rev. D 108, 083535 (2023)
In the context of $F(\phi)R$ models of gravity, the conformal invariance of the curvature perturbation on uniform-field slices has been already demonstrated in several publications. In this work we study the curvature perturbation $\mathcal{R}$ defin
Externí odkaz:
http://arxiv.org/abs/2305.15326
Primordial black holes (PBHs) are supposed to form through the gravitational collapse of regions with large density fluctuations. The formation of PBHs inevitably leads to the emission of scalar-induced gravitational wave (SIGW) signals, offering a u
Externí odkaz:
http://arxiv.org/abs/2308.07155
The recently released data by pulsar timing array (PTA) collaborations present strong evidence for a stochastic signal consistent with a gravitational-wave background. Assuming this signal originates from scalar-induced gravitational waves, we jointl
Externí odkaz:
http://arxiv.org/abs/2307.01102
Primordial black holes (PBHs) can be both candidates of dark matter and progenitors of binary black holes (BBHs) detected by the LIGO-Virgo-KAGRA collaboration. Since PBHs could form in the very early Universe through the gravitational collapse of pr
Externí odkaz:
http://arxiv.org/abs/2212.05516
Autor:
Pi, Shi, Sasaki, Misao
Publikováno v:
Phys. Rev. Lett. 131, 011002 (2023)
We study the comoving curvature perturbation $\mathcal{R}$ in the single-field inflation models whose potential can be approximated by a piecewise quadratic potential $V(\varphi)$ by using the $\delta N$ formalism. We find a general formula for $\mat
Externí odkaz:
http://arxiv.org/abs/2211.13932