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Dark Energy Survey Year 3 results: Cosmology from cosmic shear and robustness to modeling uncertainty Open
This work and its companion paper, Amon et al. [Phys. Rev. D 105, 023514 (2022)], present cosmic shear measurements and cosmological constraints from over 100 million source galaxies in the Dark Energy Survey (DES) Year 3 data. We constrai…
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Threshold for primordial black holes: Dependence on the shape of the cosmological perturbations Open
Primordial black holes may have formed in the radiative era of the early\nUniverse from the collapse of large enough amplitude perturbations of the\nmetric. These correspond to non linear energy density perturbations\ncharacterized by an a…
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An improved SPH scheme for cosmological simulations Open
We present an implementation of smoothed particle hydrodynamics (SPH) with improved accuracy for simulations of galaxies and the large-scale structure. In particular, we implement and test a vast majority of SPH improvement in the develope…
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KiDS-450: testing extensions to the standard cosmological model Open
We test extensions to the standard cosmological model with weak gravitational lensing tomography using 450 deg 2 of imaging data from the Kilo Degree Survey (KiDS). In these extended cosmologies, which include massive neutrinos, non-zero c…
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Implications of an extended dark energy cosmology with massive neutrinos for cosmological tensions Open
We perform a comprehensive analysis of the most common early- and\nlate-Universe solutions to the $H_0$, Ly-$\\alpha$, and $S_8$ discrepancies.\nWhen considered on their own, massive neutrinos provide a natural solution to\nthe $S_8$ discr…
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Cosmological moduli and the post-inflationary universe: A critical review Open
We critically review the role of cosmological moduli in determining the post-inflationary history of the universe. Moduli are ubiquitous in string and M-theory constructions of beyond the Standard Model physics, where they parametrize the …
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The Effective Field Theory of nonsingular cosmology Open
In this paper, we explore the nonsingular cosmology within the framework of\nthe Effective Field Theory(EFT) of cosmological perturbations. Due to the\nrecently proved no-go theorem, any nonsingular cosmological models based on the\ncubic …
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Limits on <i>w</i>CDM from the EFTofLSS with the PyBird code Open
We apply the Effective Field Theory of Large-Scale Structure to analyze the wCDM cosmological model. By using the full shape of the power spectrum and the BAO post-reconstruction measurements from BOSS, the Supernovae from Pantheon, and a …
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Single-field α-attractors Open
I describe a simple class of $\\alpha$-attractors, generalizing the\nsingle-field GL model of inflation in supergravity. The new class of models is\ndefined for $0<\\alpha \\lesssim 1$, providing a good match to the present\ncosmological d…
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Standard Model Background of the Cosmological Collider Open
The inflationary universe can be viewed as a "cosmological collider" with an energy of the Hubble scale, producing very massive particles and recording their characteristic signals in primordial non-Gaussianities. To utilize this collider …
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Cosmological Constraints from Multiple Probes in the Dark Energy Survey Open
The combination of multiple observational probes has long been advocated as a powerful technique to constrain cosmological parameters, in particular dark energy. The Dark Energy Survey has measured 207 spectroscopically confirmed type Ia s…
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Standard model with a complex scalar singlet: Cosmological implications and theoretical considerations Open
We analyze the theoretical and phenomenological considerations for the electroweak phase transition and dark matter in an extension of the standard model with a complex scalar singlet (cxSM). In contrast with earlier studies, we use a reno…
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Using quasar X-ray and UV flux measurements to constrain cosmological model parameters Open
Risaliti and Lusso have compiled X-ray and UV flux measurements of 1598 quasars (QSOs) in the redshift range 0.036 ≤ z ≤ 5.1003, part of which, z ∼ 2.4 − 5.1, is largely cosmologically unprobed. In this paper we use these QSO measurements,…
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Departures from the Friedmann-Lemaitre-Robertston-Walker Cosmological Model in an Inhomogeneous Universe: A Numerical Examination Open
While the use of numerical general relativity for modeling astrophysical phenomena and compact objects is commonplace, the application to cosmological scenarios is only just beginning. Here, we examine the expansion of a spacetime using th…
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Non-linear interacting cosmological models after Planck 2018 legacy release and the H0 tension Open
Interacting dark energy models are widely renowned for giving an explanation to the cosmic coincidence problem as well as several observational issues. According to the recent observational data, and so far we are concerned with the litera…
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Challenges of the Standard Cosmological Model Open
Measurements of the temperature and polarization anisotropy of the cosmic microwave background (CMB) provided strong confirmation of the vanilla flat ΛCDM model of structure formation. Even if this model fits incredibly well, the cosmologi…
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Evidence for Suppression of Structure Growth in the Concordance Cosmological Model Open
We present evidence for a suppressed growth rate of large-scale structure during the dark-energy dominated era. Modeling the growth rate of perturbations with the ``growth index'' γ, we find that current cosmological data strongly prefer a…
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Cosmological perturbations in a mimetic matter model Open
We investigate the cosmological evolution of mimetic matter model with\narbitrary scalar potential. The cosmological reconstruction, which is the way\nto construct a model for arbitrary evolutions of the scale factor, is\nexplicitly done f…
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Evidence for cosmological particle creation? Open
A joint analysis of the linear matter power spectrum, distance measurements\nfrom type Ia supernovae and the position of the first peak in the anisotropy\nspectrum of the cosmic microwave background indicates a cosmological, late-time\ndar…
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Super-resolution emulator of cosmological simulations using deep physical models Open
We present an extension of our recently developed Wasserstein optimized model to emulate accurate high-resolution (HR) features from computationally cheaper low-resolution (LR) cosmological simulations. Our deep physical modelling techniqu…
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Cosmological constraints on curved quintessence Open
Dynamical dark energy has gained renewed interest due to recent theoretical and observational developments. In the present paper, we focus on a string-motivated dark energy set-up, and perform a detailed cosmological analysis of exponentia…
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Integration of inhomogeneous cosmological spacetimes in the BSSN formalism Open
We present cosmological-scale numerical simulations of an evolving universe in full general relativity and introduce a new numerical tool, cosmograph, which employs the Baumgarte-Shapiro-Shibata-Nakamura formalism on a three-dimensional gr…
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Stability analysis for cosmological models in f(T, B) gravity Open
In this paper we study cosmological solutions of the f ( T , B ) gravity using dynamical system analyses. For this purpose, we consider cosmological viable functions of f ( T , B ) that are capable of reproducing the dynamics of the Univer…
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Through the big bang: Continuing Einstein's equations beyond a cosmological singularity Open
All measurements are comparisons. The only physically accessible degrees of freedom (DOFs) are dimensionless ratios. The objective description of the universe as a whole thus predicts only how these ratios change collectively as one of the…
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Dynamical analysis on $f(R, \mathcal{G})$ cosmology Open
We use a dynamical system approach to study the cosmological viability of\n$f(R,\\mathcal{G})$ gravity theories. The method consists of formulating the\nevolution equations as an autonomous system of ODEs, using suitable variables.\nThe fo…
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Scaling relations of fuzzy dark matter haloes – I. Individual systems in their cosmological environment Open
Dark matter models involving a very light bosonic particle, generally known as fuzzy dark matter (FDM), have been recently attracting great interest in the cosmology community, as their wave-like phenomenology would simultaneously explain …
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Cutting rule for cosmological collider signals: a bulk evolution perspective Open
A bstract We show that the evolution of interacting massive particles in the de Sitter bulk can be understood at leading order as a series of resonant decay and production events. From this perspective, we classify the cosmological collide…
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Perturbations in non-flat cosmology for f(T) gravity Open
The study of cosmological perturbation theory in f ( T ) gravity is a topic of great interest in teleparallel gravity since this is one of the simplest generalizations of the theory that modifies the teleparallel equivalent of general rela…
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Cosmological models from a geometric point of view Open
(There is no original abstract.) These are lecture notes from a 1971 summer school surveying the then known cosmological models in particular the properties of Bianchi cosmologies, and giving a pedagogical introduction to groups of isometr…
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Dynamical system analysis for a nonminimal torsion-matter coupled gravity Open
In this work, we perform a detailed dynamical analysis for the cosmological applications of a nonminimal torsion-matter coupled gravity. Two alternative formalisms are proposed, which enable one to choose between the easier approach for a …