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Related papers: Scale-dependent bias due to primordial vector fiel…

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We present a systematic study of galaxy biasing in the presence of primordial non-Gaussianity. For a large class of non-Gaussian initial conditions, we define a general bias expansion and prove that it is closed under renormalization,…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-06 Valentin Assassi , Daniel Baumann , Fabian Schmidt

Magnetic fields in the early universe could have played an important role in sourcing cosmological perturbations. While not the dominant source, even a small contribution might be traceable through its intrinsic non-Gaussianity. Here we…

Astrophysics · Physics 2008-11-26 Iain Brown , Robert Crittenden

We analytically derive a more accurate formula for the power spectrum of the biased objects with the primordial non-Gaussianity parameterized not only by the non-linearity parameter fNL, but also by gNL and tauNL which characterize the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Shuichiro Yokoyama , Takahiko Matsubara

We use the \delta N formalism to study the trispectrum T_\zeta of the primordial curvature perturbation \zeta when the latter is generated by vector field perturbations, considering the tree-level and one-loop contributions. The order of…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-12 Cesar A. Valenzuela-Toledo , Yeinzon Rodriguez

In this work we study the simultaneous effect of primordial non-Gaussianity and the modification of the gravity in $f(R)$ framework on large scale structure observations. We show that non-Gaussianity and modified gravity introduce a scale…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-12 Nareg Mirzatuny , Shahram Khosravi , Shant Baghram , Hossein Moshafi

It is possible that the primordial non-Gaussianity is dominated by the higher order terms, such as that set by $g_{NL}$, not $f_{NL}$. In this paper we derive the spectral index and running of $g_{NL}$ from a single isocurvature scalar…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Qing-Guo Huang

We discuss correlations among spectral observables as a new tool for differentiating between models for the primordial perturbation. We show that if generated in the isocurvature sector, a running of the scalar spectral index is correlated…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Kari Enqvist , David J. Mulryne , Sami Nurmi

We investigate how the consistency relations of large-scale structures are modified when the initial density field is not Gaussian. We consider both scenarios where the primordial density field can be written as a nonlinear functional of a…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-22 Patrick Valageas , Atsushi Taruya , Takahiro Nishimichi

Gravitational waves sourced by amplified scalar perturbations are a common prediction across a wide range of cosmological models. These scalar curvature fluctuations are inherently nonlinear and typically non-Gaussian. We argue that the…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-10 A. J. Iovino , S. Matarrese , G. Perna , A. Ricciardone , A. Riotto

The bispectrum vanishes for linear Gaussian fields and is thus a sensitive probe of non-linearities and non-Gaussianities in the cosmic density field. Hence, a detection of the bispectrum in the halo density field would enable tight…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-18 Tobias Baldauf , Uros Seljak , Leonardo Senatore

Enormous information about interactions is contained in the non-Gaussianities of the primordial curvature perturbations, which are essential to break the degeneracy of inflationary models. We study the primordial bispectra for G-inflation…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Fengge Zhang , Yungui Gong , Jiong Lin , Yizhou Lu , Zhu Yi

The presence of additional particles during inflation leads to non-Gaussianity in late-time correlators of primordial curvature perturbations. The shape and amplitude of this signal depend on the mass and spin of the extra particles.…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-16 Azadeh Moradinezhad Dizgah , Cora Dvorkin

Primordial non-Gaussianity is one of the most powerful probes of the inflationary epoch. The particle spectrum relevant to inflation, including masses and spins, is encoded in the precise form of statistical correlations of the adiabatic…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Eugene Chen , Daniel Green , Vincent S. H. Lee

I investigate the possibility that the observed curvature perturbation is due to a massive vector field. To avoid generating a large scale anisotropy the vector field is not taken to be driving inflation. Instead it is assumed to become…

High Energy Physics - Phenomenology · Physics 2009-11-11 Konstantinos Dimopoulos

We perform cosmological N-body simulations with non-Gaussian initial conditions generated from two independent fields. The dominant contribution to the perturbations comes from a purely Gaussian field, but we allow the second field to have…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-25 Saroj Adhikari , Sarah Shandera , Neal Dalal

Primordial, non-Gaussian perturbations can generate scale-dependent bias in the galaxy distribution. This in turn will modify correlations between galaxy positions and peculiar velocities at late times, since peculiar velocities reflect the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Yin-Zhe Ma , James E. Taylor , Douglas Scott

We investigate the effect of primordial non-Gaussianity of the local f_NL type on the auto- and cross-power spectrum of dark matter haloes using simulations of the LCDM cosmology. We perform a series of large N-body simulations of both…

Astrophysics · Physics 2015-05-13 Vincent Desjacques , Uros Seljak , Ilian T. Iliev

The large-scale clustering of galaxies can serve as a probe of primordial non-Gaussianity in the Universe competitive with the anisotropies of the CMB. Here, we present improved theoretical predictions which include an important, previously…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Vincent Desjacques , Donghui Jeong , Fabian Schmidt

If the conformal invariance of electromagnetism is broken during inflation, then primordial magnetic fields may be produced. If this symmetry breaking is generated by the coupling between electromagnetism and a scalar field---e.g. the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Robert R. Caldwell , Leonardo Motta , Marc Kamionkowski

Primordial non-Gaussianity, in particular the coupling of modes with widely different wavelengths, can have a strong impact on the large-scale clustering of tracers through a scale-dependent bias with respect to matter. We demonstrate that…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-26 Fabian Schmidt