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Related papers: A Modal Approach to Constrain Inflation through Nu…

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We use WMAP 9-year bispectrum data to constrain the free parameters of an 'effective field theory' describing fluctuations in single-field inflation. The Lagrangian of the theory contains a finite number of operators associated with unknown…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Gemma J. Anderson , Donough Regan , David Seery

We revisit an inflationary scenario in which primordial inhomogeneities arise from a quantum collapse, a stochastic mechanism described in the context of quantum collapse theories in its continuous version and within semiclassical gravity.…

General Relativity and Quantum Cosmology · Physics 2026-03-04 María Pía Piccirilli , Gabriel León , Rosa-Laura Lechuga-Solis , Daniel Sudarsky

We perform a Bayesian analysis to study possible features in the primordial inflationary power spectrum of scalar perturbations. In particular, we analyse the possibility of detecting the imprint of these primordial features in the…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-24 Micol Benetti , Jailson S. Alcaniz

We study how direct detection of the inflationary gravitational wave background constrains inflationary parameters and complements CMB polarization measurements. The error ellipsoids calculated using the Fisher information matrix approach…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-03 Sachiko Kuroyanagi , Christopher Gordon , Joseph Silk , Naoshi Sugiyama

We present constraints on inflationary dynamics and features in the primordial power spectrum of scalar perturbations using the Cosmic Microwave Background temperature, polarization data from Planck 2018 data release and updated…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-28 Dhiraj Kumar Hazra , Daniela Paoletti , Ivan Debono , Arman Shafieloo , George F. Smoot , Alexei A. Starobinsky

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…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-01 Enrico Specogna , Tatevik Vardanyan , William Giarè , Eleonora Di Valentino

With the recently published Cosmic Microwave Background data from Planck we address the optimized binning of the primordial power spectrum. As an important modification to the usual binning of the primordial spectrum, along with the…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-06 Dhiraj Kumar Hazra , Arman Shafieloo , George F. Smoot

Is there new physics hidden in the four-point function of the cosmic microwave background (CMB)? We conduct a detailed analysis of the Planck PR4 temperature and polarization trispectrum for $\ell\in[2,2048]$. Using the theoretical and…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-30 Oliver H. E. Philcox

We study the angular bispectrum of local type arising from the (possibly correlated) combination of a primordial adiabatic mode with an isocurvature one. Generically, this bispectrum can be decomposed into six elementary bispectra. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 David Langlois , Bartjan van Tent

The recent BICEP2 detection of, what is claimed to be primordial $B$-modes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Carlo R. Contaldi

In this paper we combine partial-wave (`modal') methods with a wavelet analysis of the CMB bispectrum. Our implementation exploits the advantages of both approaches to produce robust, reliable and efficient estimators which can constrain…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-14 Donough Regan , Pia Mukherjee , David Seery

Observations of the polarization of the cosmic microwave backround (CMB) have the potential to place much tighter constraints on cosmological parameters than observations of the fluctuations in temperature alone. We discuss using CMB…

Astrophysics · Physics 2009-10-30 William H. Kinney

Following Philcox et al. (2025), we investigate a scenario with a massive partner to the inflaton ($O(100)$ times the inflationary Hubble scale), in which particles are produced during a narrow time period, leaving characteristic hot- or…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-07 Luca H. Abu El-Haj , Oliver H. E. Philcox , J. Colin Hill

Motivated by BICEP2 results on the CMB polarization B-mode which imply primordial gravitational waves are produced when the Universe has the expansion rate of about $H \approx 10^{14}$ GeV, and by deviations from a smooth power-law…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-24 Dhiraj Kumar Hazra , Arman Shafieloo , George F. Smoot , Alexei A. Starobinsky

We present a machine-learning approach, based on the genetic algorithms (GA), that can be used to reconstruct the inflationary potential directly from cosmological data. We create a pipeline consisting of the GA, a primordial code and a…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-01 Ahana Kamerkar , Savvas Nesseris , Lucas Pinol

Last year we argued that if slow-roll inflation followed the decay of a false vacuum in a large landscape, the steepening of the scalar potential between the inflationary plateau and the barrier generically leads to a potentially observable…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Raphael Bousso , Daniel Harlow , Leonardo Senatore

We reconsider the original model of quadratic hybrid inflation in light of the WMAP three-year results and study the possibility of obtaining a spectral index of primordial density perturbations, $n_s$, smaller than one from this model. The…

Astrophysics · Physics 2008-11-26 Antonio Cardoso

The spectrum of primordial fluctuations from inflation can be obtained using a mathematically controlled, and systematically extendable, uniform approximation. Closed-form expressions for power spectra and spectral indices may be found…

This paper presents the CMB angular power spectrum obtained using the \texttt{CAMB} code for three different models of inflation: the Starobinsky inflationary model, the generalized Starobinsky inflationary model, and the chaotic…

General Relativity and Quantum Cosmology · Physics 2024-10-23 Daniel Pozo , Lenin Calvache , Esteban Orozco , Vicente A. Arévalo , Clara Rojas

We present an implementation of an optimal CMB trispectrum estimator which accounts for anisotropic noise and incomplete sky coverage. We use a general separable mode expansion which can and has been applied to constrain both primordial and…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-30 J. R. Fergusson , D. M. Regan , E. P. S. Shellard