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Related papers: Oscillations in the Primordial Bispectrum: Mode Ex…

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It has been shown that both scalar and tensor modes with non-Bunch-Davies initial states can enhance the amplitudes of the primordial bispectra compared to those with the Bunch-Davies state, especially for wavenumber modes in a flattened…

General Relativity and Quantum Cosmology · Physics 2023-07-13 Shingo Akama , Hiroaki W. H. Tahara

We build two families of inspiral waveforms for precessing binaries on eccentric orbits in the Fourier domain. To achieve this, we use a small eccentricity expansion of the waveform amplitudes in order to separate the periastron precession…

General Relativity and Quantum Cosmology · Physics 2018-11-29 Antoine Klein , Yannick Boetzel , Achamveedu Gopakumar , Philippe Jetzer , Lorenzo de Vittori

We give a general strategy to construct superoscillating/growing functions using an orthogonal polynomial expansion of a bandlimited function. The degree of superoscillation/growth is controlled by an anomalous expectation value of a…

Mathematical Physics · Physics 2023-11-08 Tathagata Karmakar , Andrew N. Jordan

The bispectrum, the three-point function of density fluctuations in Fourier space, is the lowest order statistic that carries information about the spatial coherence of large-scale structures. For Gaussian initial conditions, when the…

We lay the foundations for the construction of analytic expressions for Fourier-domain gravitational waveforms produced by eccentric, inspiraling compact binaries in a post-circular or small-eccentricity approximation. The time-dependent,…

General Relativity and Quantum Cosmology · Physics 2014-05-15 Nicolas Yunes , K. G. Arun , Emanuele Berti , Clifford M. Will

Sonography techniques use multiple transducer elements for tissue visualization. Signals detected at each element are sampled prior to digital beamforming. The required sampling rates are up to 4 times the Nyquist rate of the signal and…

Information Theory · Computer Science 2012-12-21 T. Chernyakova , Y. C. Eldar , R. Amit

If long wavelength primordial tensor modes are coupled to short wavelength scalar modes, the scalar curvature two-point function will have an off-diagonal component. This `fossil' remnant is a signature of a mode coupling that cannot be…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-05 Suddhasattwa Brahma , Elliot Nelson , Sarah Shandera

A statistical model for the polarization of pulsar radio emission is enhanced to account for the heavy modulation of the emission, the possible covariance of the Stokes parameters, and the observed asymmetries in the distributions of total…

High Energy Astrophysical Phenomena · Physics 2022-10-12 M. M. McKinnon

Quantitative helio- and asteroseismology require very precise measurements of the frequencies, amplitudes, and lifetimes of the global modes of stellar oscillation. It is common knowledge that the precision of these measurements depends on…

Astrophysics · Physics 2009-11-13 Thorsten Stahn , Laurent Gizon

In this study, a new expansion of planetary disturbing function is developed for describing the resonant dynamics of minor bodies with arbitrary inclinations and semimajor axis ratios. In practice, the disturbing function is expanded around…

Earth and Planetary Astrophysics · Physics 2021-12-17 Hanlun Lei

We develop and study the position-dependent bispectrum. It is a generalization of the recently proposed position-dependent power spectrum method of measuring the squeezed-limit bispectrum. The position-dependent bispectrum can similarly be…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-02 Saroj Adhikari , Donghui Jeong , Sarah Shandera

Superoscillations, i.e., the phenomenon that a bandlimited function can temporary oscillate faster than its highest Fourier component, are being much discussed for their potential for `superresolution' beyond the diffraction limit. Here, we…

Quantum Physics · Physics 2015-10-16 Achim Kempf , Angus Prain

Functions that are smooth but non-periodic on a certain interval possess Fourier series that lack uniform convergence and suffer from the Gibbs phenomenon. However, they can be represented accurately by a Fourier series that is periodic on…

Numerical Analysis · Mathematics 2015-03-19 Ben Adcock , Daan Huybrechs

This paper develops the theory behind the bispectrum, a concept that is well established in statistical signal processing but not, until recently, extended to computer vision as a source of frequency-domain invariants. Recent papers on…

Group Theory · Mathematics 2012-02-15 Ramakrishna Kakarala

The bispectrum, the three-point correlation in Fourier space, is a crucial statistic for studying many effects targeted by the next-generation galaxy surveys, such as primordial non-Gaussianity (PNG) and general relativistic (GR) effects on…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-27 Joshua N. Benabou , Adriano Testa , Chen Heinrich , Henry S. Grasshorn Gebhardt , Olivier Doré

Different inflationary models predict oscillatory features in the primordial power spectrum. These can leave an imprint on both the cosmic microwave background (CMB) and the large-scale structure (LSS) of our Universe, that can be searched…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-15 Chenxiao Zeng , Ely D. Kovetz , Xuelei Chen , Yan Gong , Julian B. Muñoz , Marc Kamionkowski

Spectral and factorization properties of oscillatory matrices leads to a spectral Favard theorem for bounded banded matrices, that admit a positive bidiagonal factorization, in terms of sequences of mixed multiple orthogonal polynomials…

Classical Analysis and ODEs · Mathematics 2022-12-21 Amílcar Branquinho , Ana Foulquié-Moreno , Manuel Mañas

A set of exactly computable orthonormal basis functions that are useful in computations involving constituent quarks is presented. These basis functions are distinguished by the property that they fall off algebraically in momentum space…

Nuclear Theory · Physics 2009-10-30 B. D. Keister , W. N. Polyzou

Oscillations in the primordial bispectrum are sourced by a range of inflationary phenomena, including features in the inflaton potential and interactions with massive fields through the Cosmological Collider scenario. These signatures offer…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-20 Samuel Goldstein , Oliver H. E. Philcox , Emanuele Fondi , William R. Coulton

In order to reconstruct the initial conditions of the universe it is important to devise a method that can efficiently constrain the shape of the power spectrum of primordial matter density fluctuations in a model-independent way from data.…

Astrophysics · Physics 2009-11-10 Pia Mukherjee , Yun Wang
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