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We generalize Doroshkevich's celebrated formulae for the eigenvalues of the initial shear field associated with Gaussian statistics to the local non-Gaussian f_{nl} model. This is possible because, to at least second order in f_{nl},…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Tsz Yan Lam , Ravi K. Sheth , Vincent Desjacques

We use the techniques of effective field theory in an expanding universe to examine the effect of choosing an excited inflationary initial state built over the Bunch-Davies state on the CMB bi-spectrum. We find that even for Hadamard…

High Energy Physics - Theory · Physics 2009-06-19 R. Holman , Andrew J. Tolley

While observations of large-scale structure and the cosmic microwave background (CMB) provide strong constraints on the amplitude of the primordial power spectrum (PPS) on scales larger than 10~Mpc, the amplitude of the power spectrum on…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Shingo Hirano , Nick Zhu , Naoki Yoshida , David Spergel , Harold W. Yorke

A coherent over- or under-density contrast across a finite survey volume causes an upward- or downward-fluctuation in the observed number of halos. This fluctuation in halo number adds a significant co-variant scatter in the observed…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Masahiro Takada , David N. Spergel

Modified matter power spectra with approximately Gaussian bump on sub-Mpc scales can be a result of a complex inflation. We consider five spectra with different Gaussian amplitudes $A$ and locations $k_0$ and run N-body simulations in a…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-15 M. V. Tkachev , S. V. Pilipenko , E. V. Mikheeva , V. N. Lukash

We studied the effect of primordial non-Gaussianity with varied bispectrum shapes on the number counts of signal-to-noise peaks in wide field cosmic shear maps. The two cosmological contributions to this particular weak lensing statistic,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. Maturi , C. Fedeli , L. Moscardini

The late-time effect of primordial non-Gaussianity offers a window into the physics of inflation and the very early Universe. In this work we study the consequences of a particular class of primordial non-Gaussianity that is fully…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 G. A. Peña , G. N. Candlish

Non-gaussianity in the initial conditions of the universe is one of the most powerful mechanisms to discriminate among the competing theories of the early universe. Measurements using bispectrum of cosmic microwave background anisotropies…

Astrophysics · Physics 2009-02-23 Uros Seljak

We study how the bounds on the abundance of Primordial Black Holes (PBHs) and the constraints on power spectrum are modified if a non-standard evolution phase takes place between the end of inflation and the Standard radiation-dominated…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-15 Tadeo D. Gomez-Aguilar , Luis E. Padilla , Encieh Erfani , Juan Carlos Hidalgo

Primordial non-Gaussianities enhanced at small wavevectors can induce a power spectrum of the galaxy overdensity that differs greatly from that of the matter overdensity at large length scales. In previous work, it was shown that "squeezed"…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-22 Michael McAneny , Alexander K. Ridgway , Mikhail P. Solon , Mark B. Wise

The decrease of both the rolling speed of the inflaton and the sound speed of the curvature perturbations can amplify the curvature perturbations during inflation so as to generate a sizable amount of primordial black holes. In the…

General Relativity and Quantum Cosmology · Physics 2024-01-17 Rongrong Zhai , Hongwei Yu , Puxun Wu

We study how primordial non-Gaussianities affect the clustering of voids at large scales. We derive a formula of the bias of voids induced from the non-Gaussianities by making use of the functional integral method. In a similar way as of…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-02 Toyokazu Sekiguchi , Shuichiro Yokoyama

We consider the consequences of a matter power spectrum which rises on small scales until eventually being cutoff by microphysical processes associated with the particle nature of dark matter. Evolving the perturbations of a weakly…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-21 Derek Inman , Kazunori Kohri

Quasars powered by massive black holes (BHs) with mass estimates above a billion solar masses have been identified at redshift 6 and beyond. The existence of such BHs requires almost continuous growth at the Eddington limit for their whole…

The next generation of cosmic microwave background, gravitational wave, and large scale structure, experiments will provide an unprecedented opportunity to probe the primordial power spectrum on small scales. An exciting possibility for…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-02 Keisuke Inomata , Evan McDonough , Wayne Hu

Primordial black holes represent a unique probe to constrain the early universe on small scales - providing the only constraints on the primordial power spectrum on the majority of scales. However, these constraints are strongly dependent…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Sam Young , Donough Regan , Christian T. Byrnes

Stellar evolution models predict the existence of a gap in the black hole mass spectrum from $\sim55 M_\odot - 120 M_\odot$ due to pair-instability supernovae (PISNe). We investigate the possible existence of such an "upper" mass gap in the…

High Energy Astrophysical Phenomena · Physics 2022-01-25 Bruce Edelman , Zoheyr Doctor , Ben Farr

Cosmological perturbations, originating in the quantum fluctuations of the fields that drive inflation, are observed to be nearly scale invariant at the largest scales. At smaller scales, however, perturbations are not severely constrained…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-09 Ioannis Dalianis

Although the spectrum of primordial fluctuations has been accurately measured on scales above $\sim 0.1~\rm{Mpc}$, only upper limits exist on smaller scales. In this study, we investigate generic monochromatic enhancements to the…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-21 Guillermo Franco Abellán , Gaétan Facchinetti

Cosmic voids in the large-scale structure are among the useful probes for testing gravity on cosmological scales. In this paper, we investigate the evolution of voids in the Horndeski theory using the effective field theory (EFT) of dark…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 Toshiki Takadera , Shin'ichi Hirano , Tsutomu Kobayashi