Zobrazeno 1 - 10
of 961
pro vyhledávání: '"primordial [perturbation]"'
Autor:
Li, Changhong
Dark matter(DM) is the only possible candidate which would be apart from the thermal equilibrium before Big Bang nucleosynthesis(BBN) in accordance with current DM searches. In this work, we report a generic scenario that primordial perturbation of d
Externí odkaz:
http://arxiv.org/abs/1710.10623
Autor:
L'Huillier, Benjamin, Shafieloo, Arman, Hazra, Dhiraj Kumar, Smoot, George F., Starobinsky, Alexei A.
Publikováno v:
MNRAS 477, 2503-2512 (2018)
The form of the primordial power spectrum (PPS) of cosmological scalar (matter density) perturbations is not yet constrained satisfactorily in spite of the tremendous amount of information from the Cosmic Microwave Background (CMB) data. While a smoo
Externí odkaz:
http://arxiv.org/abs/1710.10987
Autor:
Piao, Yun-Song
Publikováno v:
Phys.Lett.B681:1-4,2009
Recently, Ho\v{r}ava has proposed a renormalizable theory of gravity with critical exponent z=3 in the UV. This proposal might imply the scale invariant primordial perturbation can be generated in any expansion of early universe with a\sim t^n and n>
Externí odkaz:
http://arxiv.org/abs/0904.4117
Autor:
Liu, Jie, Piao, Yun-Song
We show that if the inflaton effective potential has multiple discontinuous points in its first derivative, the spectrum of primordial perturbation will be multiple step-like. We give a general analysis by applying a simple model. In principle, as lo
Externí odkaz:
http://arxiv.org/abs/1106.5608
Autor:
Cai, Yi-Fu, Zhang, Xinmin
Publikováno v:
Phys.Rev.D80:043520,2009
In this paper we study the generation of primordial perturbation with a modified dispersion relation in various cosmological evolutions. We stress that the formation of the power spectrum is strongly dependent on the background. Working in a bounce m
Externí odkaz:
http://arxiv.org/abs/0906.3341
Autor:
Piao, Yun-Song, Zhang, Yuan-Zhong
Publikováno v:
Phys.Rev. D70 (2004) 043516
In this paper, focusing on the case of single scalar field, we discuss various expanding and contracting phases generating primordial perturbations, and study the relation between the primordial perturbation spectrum from these phases and the paramet
Externí odkaz:
http://arxiv.org/abs/astro-ph/0403671
Autor:
Zhang, Hongsheng, Li, Xin-Zhou
Publikováno v:
JHEP 1106:043,2011
Scalar-tensor gravity is one of the most competitive gravity theory to Einstein's relativity. We reconstruct the exact de Sitter solution in scalar-tensor gravity, in which the non-minimal coupling scalar is rolling along the potential. This solution
Externí odkaz:
http://arxiv.org/abs/1007.3096
Publikováno v:
Phys.Rev.D74:103003,2006
We use the delta N -formalism to investigate the non-Gaussianity of the primordial curvature perturbation in the curvaton scenario for the origin of structure. We numerically calculate the full probability distribution function allowing for the non-i
Externí odkaz:
http://arxiv.org/abs/astro-ph/0607627
Autor:
Piao, Yun-Song
Publikováno v:
Phys.Lett. B606 (2005) 245-250
In this paper, we discuss the dualities of the primordial perturbation spectra from various expanding/contracting phases for full space of parameter $w\equiv {p\over \rho}$ of state equation.
Comment: 5 pages, 2 eps figures, published in PLB606
Comment: 5 pages, 2 eps figures, published in PLB606
Externí odkaz:
http://arxiv.org/abs/hep-th/0404002
Autor:
Piao, Yun-Song, Zhang, Yuan-Zhong
Publikováno v:
Phys.Rev. D70 (2004) 063513
In this paper we study the inflation model driven by the phantom field. We propose a possible exit from phantom inflation to our observational cosmology by introducing an additional normal scalar field, similar to hybrid inflation model. Then we disc
Externí odkaz:
http://arxiv.org/abs/astro-ph/0401231