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We present a new independent pipeline for the CMB bispectrum estimation of primordial non-Gaussianity and release a public code for constraining bispectrum shapes of interest based on the Planck 2018 temperature and polarization data. The…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-06 Wuhyun Sohn , James R. Fergusson , E. P. S. Shellard

The form of the primordial power spectrum (PPS) of cosmological scalar (matter density) perturbations is not yet constrained satisfactorily in spite of the tremendous amount of information from the Cosmic Microwave Background (CMB) data.…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-21 Benjamin L'Huillier , Arman Shafieloo , Dhiraj Kumar Hazra , George F. Smoot , Alexei A. Starobinsky

The best-fit values of the density parameter and the amplitude of the linear density power spectrum obtained from the Cosmic Microwave Background (CMB) temperature field scanned by the Planck satellite are found to notably disagree with…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Jounghun Lee

We explore the relationship between features in the Planck 2015 temperature and polarization data, shifts in the cosmological parameters, and features from inflation. Residuals in the temperature data at low multipole $\ell$, which are…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-18 Georges Obied , Cora Dvorkin , Chen Heinrich , Wayne Hu , V Miranda

We revisit the observational constraints on spatial curvature following recent claims that the Planck data favour a closed Universe. We use a new and statistically powerful Planck likelihood to show that the Planck temperature and…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-03 George Efstathiou , Steven Gratton

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

We propose a straightforward and model independent methodology for characterizing the sensitivity of CMB and other experiments to wiggles, irregularities, and features in the primordial power spectrum. Assuming that the primordial…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Christopher Gauthier , Martin Bucher

We discuss the model selection problem for inflationary cosmology. We couple ModeCode, a publicly-available numerical solver for the primordial perturbation spectra, to the nested sampler MultiNest, in order to efficiently compute Bayesian…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-01 Richard Easther , Hiranya Peiris

We use data from the nominal Planck mission to constrain modulations in the primordial power spectrum associated with monodromy inflation. The largest improvement in fit relative to the unmodulated model has \Delta\chi^2~10 and we find no…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 Richard Easther , Raphael Flauger

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 explore the warm inflation scenario theoretical predictions looking at two different dissipative regimes for several representative primordial potentials. As it is well known, the warm inflation is able to decrease the tensor-to-scalar…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-03 Micol Benetti , Rudnei O. Ramos

We investigate the effect of damped oscillations on a nearly flat inflationary potential and the features they produce in the power-spectrum and bi-spectrum. We compare the model with the Planck data using Plik unbinned and CamSpec clean…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-20 Akhil Antony , Shweta Jain

The first year of observations by the Planck satellite mission shows that the cosmic microwave background (CMB) fluctuations are consistent with gaussian statistics in the primordial perturbations, a key prediction of the simplest models of…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-19 Ana Achucarro , Vicente Atal , Pablo Ortiz , Jesus Torrado

I present a new procedure to forecast the Bayes factor of a future observation by computing the Predictive Posterior Odds Distribution (PPOD). This can assess the power of future experiments to answer model selection questions and the…

Astrophysics · Physics 2008-11-26 Roberto Trotta

The measurements of the temperature and polarisation anisotropies of the Cosmic Microwave Background (CMB) by the ESA Planck mission have strongly supported the current concordance model of cosmology. However, the latest cosmological data…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-10 I. Ocampo , G. Cañas-Herrera , S. Nesseris

We show that results from the Planck satellite reported in 2013 are consistent with the simplest cyclic models for natural parameter ranges i.e., order unity dimensionless coefficients, assuming the standard entropic mechanism for…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Jean-Luc Lehners , Paul J. Steinhardt

The current available CMB data show an anomalously low value of the CMB temperature fluctuations at large angular scales (l < 40). This lack of power is not explained by the minimal LCDM model, and one of the possible mechanisms explored in…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-07 Simony Santos da Costa , Micol Benetti , Jailson Alcaniz

We use Bayesian model selection tools to forecast the Planck satellite's ability to distinguish between different models for the reionization history of the Universe, using the large angular scale signal in the cosmic microwave background…

Astrophysics · Physics 2009-11-13 Pia Mukherjee , Andrew R. Liddle

Modern cosmological data demand modern data analysis techniques. We introduce BayOp, a new likelihood sampling and maximisation method which is based on the Bayesian Optimisation algorithm and learns a function instead of randomly sampling…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-15 Jan Hamann , Julius Wons

We investigate the possibility of using future photometric and radio surveys to constrain the power spectrum of primordial fluctuations that is predicted by inflationary models with a violation of the slow-roll phase. We forecast…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-17 Mario Ballardini , Fabio Finelli , Roy Maartens , Lauro Moscardini