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相关论文: A new method for calculating the primordial bispec…

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Calculating the primordial bispectrum predicted by a model of inflation and comparing it to what we see in the sky is very computationally intensive, necessitating layers of approximations and limiting the models which can be constrained.…

宇宙学与河外天体物理 · 物理学 2021-08-11 Philip Clarke , E. P. S. Shellard

Constraining inflationary models with high precision bispectra across broad parameter ranges is a challenging task, requiring intensive computations at all stages, first, predicting the primordial inflation bispectrum from quantum field…

宇宙学与河外天体物理 · 物理学 2025-12-29 Bowei Zhang , E. P. S. Shellard , James R. Fergusson

We discuss bispectra of single-field inflationary models described by general Lorentz invariant Lagrangians that are at most first order in field derivatives, including the fast-roll models investigated by Noller and Magueijo. Based on a…

宇宙学与河外天体物理 · 物理学 2011-12-22 Thorsten Battefeld , Jan Grieb

We study features in the bispectrum of the primordial curvature perturbation correlated with the reconstructed primordial power spectrum from the observed cosmic microwave background temperature data. We first show how the bispectrum can be…

宇宙学与河外天体物理 · 物理学 2017-12-25 Stephen Appleby , Jinn-Ouk Gong , Dhiraj Kumar Hazra , Arman Shafieloo , Spyros Sypsas

We derive a direct correlation between the power spectrum and bispectrum of the primordial curvature perturbation in terms of the Goldstone mode based on the effective field theory approach to inflation. We show examples of correlated…

宇宙学与河外天体物理 · 物理学 2017-04-19 Jinn-Ouk Gong , Masahide Yamaguchi

We compute the full bispectra, namely both auto- and cross- bispectra, of primordial curvature and tensor perturbations in the most general single-field inflation model whose scalar and gravitational equations of motion are of second order.…

宇宙学与河外天体物理 · 物理学 2015-03-20 Xian Gao , Tsutomu Kobayashi , Maresuke Shiraishi , Masahide Yamaguchi , Jun'ichi Yokoyama , Shuichiro Yokoyama

We revisit the Cosmic Microwave Background (CMB) constraints on the spatial curvature of the Universe, assessing how they change when the curvature parameter and the primordial inflationary scalar spectrum are treated consistently within…

宇宙学与河外天体物理 · 物理学 2025-10-01 Enrico Specogna , Tatevik Vardanyan , William Giarè , Eleonora Di Valentino

In the Horndeski's most general scalar-tensor theories, we derive the three-point correlation function of scalar non-Gaussianities generated during single-field inflation in the presence of slow-variation corrections to the leading-order…

高能物理 - 理论 · 物理学 2015-06-12 Antonio De Felice , Shinji Tsujikawa

We investigate the symmetry constraints on the bispectrum, i.e. the three-point correlation function of primordial density fluctuations, in slow-roll inflation. It follows from the defining property of slow-roll inflation that primordial…

高能物理 - 理论 · 物理学 2013-03-29 Koenraad Schalm , Gary Shiu , Ted van der Aalst

An elegant approach, which incorporates the effect of the stringy spacetime uncertainty relation, to calculate power spectra of fluctuations during inflation has been suggested by Brandenberger and Ho. In this approach, one of important…

高能物理 - 理论 · 物理学 2009-11-10 Rong-Gen Cai

Combining Planck CMB temperature [1] and BICEP2 B-mode polarization data [2,3] we show qualitatively that, assuming inflationary consistency relation, the power-law form of the scalar primordial spectrum is ruled out at more than $3\sigma$…

宇宙学与河外天体物理 · 物理学 2014-07-17 Dhiraj Kumar Hazra , Arman Shafieloo , George F. Smoot , Alexei A. Starobinsky

We compute the primordial trispectrum for curvature perturbations produced during cosmic inflation in models with standard kinetic terms, when the initial quantum state is not necessarily the vacuum state. The presence of initial…

宇宙学与河外天体物理 · 物理学 2015-06-03 Ivan Agullo , Jose Navarro-Salas , Leonard Parker

We investigate constraints on power spectra of the primordial curvature and tensor perturbations with priors based on single-field slow-roll inflation models. We stochastically draw the Hubble slow-roll parameters and generate the…

宇宙学与河外天体物理 · 物理学 2014-11-20 Masahiro Kawasaki , Toyokazu Sekiguchi

The recently proposed model of 'solid inflation' features a peculiar three-point function for scalar perturbations with an anisotropic, purely quadrupolar, squeezed limit. We confirm this result as well as the overall amplitude of the three…

高能物理 - 理论 · 物理学 2014-09-10 Solomon Endlich , Bart Horn , Alberto Nicolis , Junpu Wang

Recently, there has been some interest for building supersymmetric models of double inflation. These models, realistic from a particle physics point of view, predict a broken-scale-invariant power spectrum of primordial cosmological…

高能物理 - 唯象学 · 物理学 2014-11-17 Julien Lesgourgues

Using the consistency relation in Fourier space, we derive the observed galaxy bispectrum from single-field inflation in the squeezed limit, in which one of the three modes has a wavelength much longer than the other two. This provides a…

宇宙学与河外天体物理 · 物理学 2018-07-31 Kazuya Koyama , Obinna Umeh , Roy Maartens , Daniele Bertacca

Modeling the nonlinearity of the halo bispectrum remains a major challenge in modern cosmology, in particular for ongoing and upcoming large-scale structure observations that are performed to study the inflationary physics. The "power…

宇宙学与河外天体物理 · 物理学 2017-06-21 Chi-Ting Chiang

We re-examine approximations in the analytical calculation of the primordial spectrum of cosmological perturbation produced during inflation. Taking two inflation models (chaotic inflation and natural inflation) as examples, we numerically…

高能物理 - 唯象学 · 物理学 2009-10-31 D. H. Huang , W. B. Lin , X. M. Zhang

According to the equivalence principal, the long wavelength perturbations must not have any dynamical effect on the short scale physics up to ${\cal O} (k_L^2/k_s^2)$. Their effect can be always absorbed to a coordinate transformation…

宇宙学与河外天体物理 · 物理学 2018-08-29 Ali Akbar Abolhasani , Misao Sasaki

We compute the leading order contribution to the four-point function of the primordial curvature perturbation in a class of single field models where the inflationary Lagrangian is a general function of the inflaton and its first…

高能物理 - 理论 · 物理学 2008-12-04 Xingang Chen , Min-xin Huang , Gary Shiu