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Related papers: Optimal CMB estimators for bispectra from excited …

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We propose an (optimal) estimator for a CMB bispectrum containing logarithmically spaced oscillations. There is tremendous theoretical interest in such bispectra, and they are predicted by a plethora of models, including axion monodromy…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-05 Moritz Münchmeyer , P. Daniel Meerburg , Benjamin D. Wandelt

Various data analyses of the Cosmic Microwave Background (CMB) provide observational hints of statistical isotropy breaking. Some of these features can be studied within the framework of primordial vector fields in inflationary theories…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 N. Bartolo , E. Dimastrogiovanni , M. Liguori , S. Matarrese , A. Riotto

The excited state dynamics of chromophores in complex environments determine a range of vital biological and energy capture processes. Time-resolved, multidimensional optical spectroscopies provide a key tool to investigate these processes.…

We use the techniques of effective field theory in an expanding universe to examine the effect of choosing an excited inflationary initial state built over the Bunch-Davies state on the CMB bi-spectrum. We find that even for Hadamard…

High Energy Physics - Theory · Physics 2009-06-19 R. Holman , Andrew J. Tolley

We present a new flexible estimator for comparing theoretical templates for the predicted bispectrum of the CMB anisotropy to observations. This estimator, based on binning in harmonic space, generalizes the optimal estimator of Komatsu,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Martin Bucher , Bartjan Van Tent , Carla Sofia Carvalho

Fast robust methods for calculating likelihoods from CMB observations on small scales generally rely on approximations based on a set of power spectrum estimators and their covariances. We investigate the optimality of these approximation,…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Samira Hamimeche , Antony Lewis

Modifications of the initial-state of the inflaton field can induce a departure from Gaussianity and leave a testable imprint on the higher order correlations of the CMB and large scale structures in the Universe. We focus on the bispectrum…

High Energy Physics - Theory · Physics 2010-01-05 Pieter Daniel Meerburg , Jan Pieter van der Schaar , Pier Stefano Corasaniti

It is widely believed that maximum likelihood estimators must be used to provide optimal estimates of power spectra. Since such estimators require require of order N_d^3 operations they are computationally prohibitive for N_d greater than a…

Astrophysics · Physics 2008-11-26 G. Efstathiou

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

We present trispectrum estimation methods which can be applied to general non-separable primordial and CMB trispectra. We present a general optimal estimator for the connected part of the trispectrum, for which we derive a quadratic term to…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 D. M. Regan , E. P. S. Shellard , J. R. Fergusson

The simplest inflationary models present us with few observable parameters to discriminate between them. A detection of features in the spectra of primordial density perturbations could provide valuable insights and lead to stringent tests…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-14 J. R. Fergusson , H. F. Gruetjen , E. P. S. Shellard , M. Liguori

Forthcoming high-resolution observations of the Cosmic Microwave Background (CMB) radiation will generate datasets many orders of magnitude larger than have been obtained to date. The size and complexity of such datasets presents a very…

Astrophysics · Physics 2016-08-25 Julian Borrill

The difference of the values of observables for the time-independent Schroedinger equation, with matrix valued potentials, and the values of observables for ab initio Born-Oppenheimer molecular dynamics, of the ground state, depends on the…

Numerical Analysis · Mathematics 2015-05-13 Christian Bayer , Hakon Hoel , Ashraful Kadir , Petr Plechac , Mattias Sandberg , Anders Szepessy

We use a separable mode expansion estimator with WMAP data to estimate the bispectrum for all the primary families of non-Gaussian models. We review the late-time mode expansion estimator methodology which can be applied to any…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 J. R. Fergusson , M. Liguori , E. P. S. Shellard

We describe a general expansion of spherical (full-sky) bispectra into a set of orthogonal modes. For squeezed shapes, the basis separates physically-distinct signals and is dominated by the lowest moments. In terms of reduced bispectra, we…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-23 Julien Carron , Antony Lewis

Massive quantum oscillators are finding increasing applications in proposals for high-precision quantum sensors and interferometric detection of weak forces. Although optimal estimation of certain properties of massive quantum oscillators…

Quantum Physics · Physics 2025-10-10 Tyler Volkoff , Giri Gopalan

We investigate if the hemispherical asymmetry in the CMB is produced from "asymmetric" excited initial condition. We show that in the limit where the deviations from the Bunch-Davies vacuum is large and the scale of new physics is maximally…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-07 Amjad Ashoorioon , Tomi Koivisto

Constructing a fast and efficient estimator for the B-mode power spectrum of cosmic microwave background (CMB) is of critical importance for CMB science. For a general CMB survey, the Quadratic Maximum Likelihood (QML) estimator for CMB…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-17 Jiming Chen , Shamik Ghosh , Hao Liu , Larissa Santos , Wenjuan Fang , Siyu Li , Yang Liu , Hong Li , Jiaxin Wang , Le Zhang , Bin Hu , Wen Zhao

We propose a factorizability ansatz for angular bispectra which permits fast algorithms for forecasting, analysis, and simulation, yet is general enough to encompass many interesting CMB bispectra. We describe a suite of general algorithms…

Astrophysics · Physics 2011-11-09 Kendrick M. Smith , Matias Zaldarriaga

This work presents a series of highly-accurate excited-state properties obtained using high-order coupled-cluster (CC) calculations performed with a series of diffuse containing basis sets, as well as extensive comparisons with experimental…

Chemical Physics · Physics 2021-06-14 Amara Chrayteh , Aymeric Blondel , Pierre-François Loos , Denis Jacquemin
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