401 citations · 2.9k across the 56 of their papers we have counts for
26 papers · 1 filter
Slowly Rolling on a Quantum Correction
Ido Ben-Dayan, Ayushi Srivastava, Amresh Verma
Recent advances in cosmological measurements such as DESI and ACT may indicate an increase in the preferred value of the spectral tilt such that it disfavors rather popular m…
Disentangling the Origins of the NANOGrav Signal: Early Universe Models and Bounds
Ido Ben-Dayan, Utkarsh Kumar, Amresh Verma
We investigate whether an Early-Universe stochastic gravitational-wave background (SGWB) can account for the common spectrum process reported by NANOGrav, while also being consiste…
The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
Eleonora Di Valentino, Jackson Levi Said, Adam Riess +533
The standard model of cosmology has provided a good phenomenological description of a wide range of observations both at astrophysical and cosmological scales for several decades.…
Impact of Low ell's on Large Scale Structure Anomalies
Ido Ben-Dayan, Utkarsh Kumar, Meir Shimon +1
We scrutinize the reported lensing anomaly of the CMB by considering several phenomenological modifications of the lensing consistency parameter, . Considering Planck sp…
Theoretical Priors and the Dark Energy Equation of State
Ido Ben-Dayan, Utkarsh Kumar
We revisit the theoretical priors used for inferring Dark Energy (DE) parameters. Any DE model must have some form of a tracker mechanism such that it behaved as matter or radiatio…
Requiem to "Proof of Inflation" or Sourced Fluctuations in a Non-Singular Bounce
Ido Ben-Dayan, Udaykrishna Thattarampilly
Popular wisdom suggests that measuring the tensor to scalar ratio on CMB scales is a "proof of inflation" since one generic prediction is a scale-invariant tensor spectrum whil…
Probing The Early Universe Cosmology With NANOGrav: Possibilities and Limitations
Ido Ben-Dayan, Utkarsh Kumar, Udaykrishna Thattarampilly +1
A stochastic gravitational wave background is a prediction of a number of astrophysical and cosmological phenomena including early Universe Cosmology. Recently, the NANOGrav Collab…
Emergent Unparticles Dark Energy can restore cosmological concordance
Ido Ben-Dayan, Utkarsh Kumar
Addressing the discrepancy between the late and early time measurements of the Hubble parameter, , and the so-called parameter has been a challenge in precision cosmolog…
Small Field models with ACTPol and BICEP3 data -- Likelihood analysis
Ira Wolfson, Utkarsh Kumar, Ido Ben-Dayan +1
We perform a Bayesian analysis for small field models of inflation, using the most recent datasets produced by Planck`18, ACTPol, and BICEP3. We employ Artificial Neural Networks (…
Cosmology with the Laser Interferometer Space Antenna
Pierre Auclair, David Bacon, Tessa Baker +177
The Laser Interferometer Space Antenna (LISA) has two scientific objectives of cosmological focus: to probe the expansion rate of the universe, and to understand stochastic gravita…
More on Emergent Dark Energy from Unparticles
Michał Artymowski, Ido Ben-Dayan, Utkarsh Kumar
In a recent paper \cite{Artymowski:2020zwy} we suggested the possibility that the present acceleration of the Universe is due to thermodynamical behavior of unparticles. The model…
Spectral Distortions of the CMB as a Probe of Inflation, Recombination, Structure Formation and Particle Physics
J. Chluba, A. Kogut, S. P. Patil +98
Following the pioneering observations with COBE in the early 1990s, studies of the cosmic microwave background (CMB) have focused on temperature and polarization anisotropies. CMB…
Constraints on Scalar and Tensor spectra from
Ido Ben-Dayan, Brian Keating, David Leon +1
At the linear level, the gravitational wave (GW) spectrum predicted by inflation, and many of its alternatives, can have arbitrarily small amplitude and consequently an unconstrain…
Gravitational Waves in Bouncing Cosmologies from Gauge Field Production
Ido Ben-Dayan
We calculate the gravitational waves (GW) spectrum produced in various Early Universe scenarios from gauge field sources, thus generalizing earlier inflationary calculations to bou…
Constraints on small-scale cosmological fluctuations from SNe lensing dispersion
Ido Ben-Dayan, Ryuichi Takahashi
We provide predictions on small-scale cosmological density power spectrum from supernova lensing dispersion. Parameterizing the primordial power spectrum with running and runni…
On Soft Limits of Large-Scale Structure Correlation Functions
Ido Ben-Dayan, Thomas Konstandin, Rafael A. Porto +1
We study soft limits of correlation functions for the density and velocity fields in the theory of structure formation. First, we re-derive the (resummed) consistency conditions at…
Lensing dispersion of SNIa and small scales of the primordial power spectrum
Ido Ben-Dayan
Probing the primordial power spectrum at small scales is crucial for discerning inflationary models, especially if BICEP2 results are confirmed. We demonstrate this necessity by br…
The value of H_0 in the inhomogeneous Universe
Ido Ben-Dayan, Ruth Durrer, Giovanni Marozzi +1
Local measurements of the Hubble expansion rate are affected by structures like galaxy clusters or voids. Here we present a fully relativistic treatment of this effect, studying ho…
Constraining the primordial power spectrum from SNIa lensing dispersion
Ido Ben-Dayan, Tigran Kalaydzhyan
The (absence of detecting) lensing dispersion of Supernovae type Ia (SNIa) can be used as a novel and extremely efficient probe of cosmology. In this preliminary example we analyze…
Average and dispersion of the luminosity-redshift relation in the concordance model
I. Ben-Dayan, M. Gasperini, G. Marozzi +2
Starting from the luminosity-redshift relation recently given up to second order in the Poisson gauge, we calculate the effects of the realistic stochastic background of perturbati…
The second-order luminosity-redshift relation in a generic inhomogeneous cosmology
Ido Ben-Dayan, Giovanni Marozzi, Fabien Nugier +1
After recalling a general non-perturbative expression for the luminosity-redshift relation holding in a recently proposed "geodesic light-cone" gauge, we show how it can be transfo…
Do stochastic inhomogeneities affect dark-energy precision measurements?
Ido Ben-Dayan, Maurizio Gasperini, Giovanni Marozzi +2
The effect of a stochastic background of cosmological perturbations on the luminosity-redshift relation is computed to second order through a recently proposed covariant and gauge-…
Backreaction on the luminosity-redshift relation from gauge invariant light-cone averaging
Ido Ben-Dayan, Maurizio Gasperini, Giovanni Marozzi +2
Using a recently proposed gauge invariant formulation of light-cone averaging, together with adapted "geodesic light-cone" coordinates, we show how an "induced backreaction" effect…
Probing the inflaton: Small-scale power spectrum constraints from measurements of the CMB energy spectrum
Jens Chluba, Adrienne L. Erickcek, Ido Ben-Dayan
In the early Universe, energy stored in small-scale density perturbations is quickly dissipated by Silk-damping, a process that inevitably generates mu- and y-type spectral distort…