Smooth primordial power spectrum : Having investigating all the above issues, we present a smooth PPS which can be described by a simple form. The primordial power spectrum features induced by the time-dependent sound speed inflationary paradigm studied here are translated into non-negligible signatures in the photon temperature and polarization anisotropies as well as in the galaxy clustering power spectrum, as … It is believed that the primordial power spectrum, formed during the inﬂation epoch, is a scale-free Harrison-Zeldovich power law. All the primordial power spectrum top hats have the same absolute height. power-law primordial spectrum. and obtain the primordial power spectrum for gravitational waves. All the primordial power spectrum top hats have the same absolute height. Observations indicate that the primordial power spectrum is consistent with being almost purely adiabatic and close to scale invariant, in agreement with expectations from the simplest inﬂationary models. Powers. Sharp features in the primordial power spectrum are a powerful window into the in ationary epoch. However, there exist a large number of well-motivated theoretical scenarios in which large non-gaussianties could be generated. Using modified Richardson-Lucy algorithm we reconstruct the primordial power spectrum (PPS) from Planck Cosmic Microwave Background (CMB) temperature anisotropy data. In this paper, we demonstrate the power of large-scale structure observations to surpass the CMB as a probe of primordial features. We develop a new approach towards a high-resolution non-parametric reconstruction of the primordial power spectrum using the Wilkinson Microwave Anisotropy Probe (WMAP) cosmic microwave background temperature anisotropies that we confront with Sloan Digital Sky Survey large-scale structure data in the range k∼ 0.01–0.1 h Mpc −1. The primordial power spectrum is parameterized as a power law P p (k) k n, with n = 1 corresponding to scale-invariant spectrum proposed by Harrison and Zeldovich on the grounds that any other value would imply a preferred mass scale for fluctuations entering the Hubble horizon. Reconstructed error-band for the form of the primordial spectrum using many realizations of the data, all bootstrapped and based on WMAP 9 year data, shows proper consistency of power-law form of the primordial spectrum with the WMAP 9 data at all wave numbers. See a different derivation of this primordial power spectrum in "Quantum Fluctuations and Cosmic Structures". Browse our catalogue of tasks and access state-of-the-art solutions. Reconstructed error-band for the form of the primordial spectrum using many realizations of the data, all bootstrapped and based on WMAP 9 year data, shows proper consistency of power-law form of the primordial spectrum with the WMAP 9 data at all wave numbers. … 2019, respectively).. 4, the angular correlation coefﬁcients for ten-sor perturbations are given. Summary of the content of this thesis 3 fluctuations is largely independent of scale size, which leads to perturbations on all scales having approximately the same amplitude. In our analysis we use different combinations of angular power spectra from Planck to reconstruct the shape of the primordial power spectrum and locate possible features. Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share … As a consistency test, we found the reconstructed primordial power spectrum from Planck temperature data can also substantially improve the fit to WMAP-9 angular power spectrum data (with respect to power-law form of the PPS) allowing an overall amplitude shift of ∼ 2.5%. Conclusions and remarks are presented in Sect. 15,113 Pages. spectral index of primordial power spectrum. 5. arXiv:0912.2728v2 [astro-ph.CO] 8 Apr 2010. Keywords: CMBR theory, cosmological parameters from CMBR, initial conditions and eternal universe. 1. PRISM: Sparse recovery of the primordial power spectrum P. Paykari et al 2014 Astronomy & Astrophysics 566 A77 Crossref. We tested four parameterizations taking into account the uncertainties in four cosmological parameters. Primordial power spectrum inference¶. This paper is organized as follows. In section2we discuss the main algorithm of the reconstruction. Searching for oscillations in the primordial power spectrum. The primordial power spectrum describes the initial perturbations that seeded the large-scale structure we observe today. We expect the smooth PPS to contain only signi cant features in the data, which might be coming from some underlying physical e ects. Active 2 months ago. This scale-free power spec-trum is transformed during the radiation-dominated expansion, the transformation depends on cosmological parameters and on the nature of the DM. The primordial power spectrum inference model defines a prior (power_spectrum.prior) and a selfi child class (power_spectrum.selfi), which allows optimization of prior hyperparameters (see sections II.C and II.E in Leclercq et al. Spectral index depends on cosmological parameters and on the nature of the more im portant results in.. 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