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Related papers: A Model for the Squeezed Bispectrum in the Non-Lin…

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We develop a model reduction technique for non-smooth dynamical systems using spectral submanifolds. Specifically, we construct low-dimensional, sparse, nonlinear and non-smooth models on unions of slow and attracting spectral submanifolds…

Dynamical Systems · Mathematics 2023-12-25 Leonardo Bettini , Mattia Cenedese , George Haller

Many high-dimensional data sets suffer from hidden confounding which affects both the predictors and the response of interest. In such situations, standard regression methods or algorithms lead to biased estimates. This paper substantially…

Methodology · Statistics 2024-12-17 Cyrill Scheidegger , Zijian Guo , Peter Bühlmann

Recent studies have demonstrated that {\em secondary} non-Gaussianity induced by gravity will be detected with a high signal-to-noise (S/N) by future and even by on-going weak lensing surveys. One way to characterise such non-Gaussianity is…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-05 D. Munshi , T. Namikawa , T. D. Kitching , J. D. McEwen , R. Takahashi , F. R. Bouchet , A. Taruya , B. Bose

While data-driven model reduction techniques are well-established for linearizable mechanical systems, general approaches to reducing non-linearizable systems with multiple coexisting steady states have been unavailable. In this paper, we…

Dynamical Systems · Mathematics 2022-07-13 Mattia Cenedese , Joar Axås , Haocheng Yang , Melih Eriten , George Haller

In this paper, we verify the large scale structure consistency relations using N-body simulations, including modes in the highly non-linear regime. These relations (pointed out by Kehagias & Riotto and Peloso & Pietroni) follow from the…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-30 Angelo Esposito , Lam Hui , Roman Scoccimarro

We provide a new fitting formula of the matter bispectrum in the nonlinear regime calibrated by high-resolution cosmological $N$-body simulations of $41$ cold dark matter ($w$CDM, $w=$ constant) models around the Planck 2015 best-fit…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-10 Ryuichi Takahashi , Takahiro Nishimichi , Toshiya Namikawa , Atsushi Taruya , Issha Kayo , Ken Osato , Yosuke Kobayashi , Masato Shirasaki

Very high dimensional nonlinear systems arise in many engineering problems due to semi-discretization of the governing partial differential equations, e.g. through finite element methods. The complexity of these systems present…

Optimization and Control · Mathematics 2022-09-15 Florian Mahlknecht , John Irvin Alora , Shobhit Jain , Edward Schmerling , Riccardo Bonalli , George Haller , Marco Pavone

We show how consistency relations can be used to robustly extract the amplitude of local primordial non-Gaussianity ($f_{\rm NL}$) from the squeezed limit of the matter bispectrum, well into the non-linear regime. First, we derive a…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-10 Samuel Goldstein , Angelo Esposito , Oliver H. E. Philcox , Lam Hui , J. Colin Hill , Roman Scoccimarro , Maximilian H. Abitbol

In order to constrain ultra light dark matter models with current and near future weak lensing surveys we need the predictions for the non-linear dark matter power-spectrum. This is commonly extracted from numerical simulations or from…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-15 Dennis Fremstad , Hans A. Winther

To investigate and specify the statistical properties of cosmological fields with particular attention to possible non-Gaussian features, accurate formulae for the bispectrum and the bispectrum covariance are required. The bispectrum is the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Sandra Martin , Peter Schneider , Patrick Simon

We evaluate for the first time the dark matter bispectrum of large-scale structure at two loops in the Standard Perturbation Theory and at three loops in the Renormalised Perturbation Theory (MPTbreeze formalism), removing in each case the…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-07 Andrei Lazanu , Michele Liguori

We study the matter bispectrum of large structure by comparing theoretical models (perturbation theories and halo models) to numerical simulations using shape and amplitude correlators. We show that among the perturbation theories at one…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-19 Andrei Lazanu

We show that in a certain, angle-averaged squeezed limit, the $N$-point function of matter is related to the response of the matter power spectrum to a long-wavelength density perturbation,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-09 Christian Wagner , Fabian Schmidt , Chi-Ting Chiang , Eiichiro Komatsu

We describe an approximate statistical model for the sample variance distribution of the non-linear matter power spectrum that can be calibrated from limited numbers of simulations. Our model retains the common assumption of a multivariate…

Theories of dark matter that support bound states are an intriguing possibility for the identity of the missing mass of the Universe. This article proposes a class of models of supersymmetric composite dark matter where the interactions…

High Energy Physics - Phenomenology · Physics 2011-09-08 Siavosh R. Behbahani , Martin Jankowiak , Tomas Rube , Jay G. Wacker

In this paper, we present a non-Gaussianity consistency relation that enables the calculation of the squeezed limit bispectrum of the curvature perturbation in single-field inflationary models by carefully inspecting the background…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-22 Mohammad Hossein Namjoo

We consider the problem of estimating cross-spectral quantities in the low-frequency regime, where long observation times limit averaging over large ensembles of periodograms, thereby preventing the use of approximate Gaussian statistics.…

Instrumentation and Methods for Astrophysics · Physics 2026-04-16 Lorenzo Sala , Stefano Vitale

We consider modeling for strong-strong beam-beam interactions beyond preceding linearized/perturbative methods such as soft gaussian approximation or FMM (HFMM) etc. In our approach discrete coherent modes, discovered before, and possible…

Accelerator Physics · Physics 2007-05-23 Antonina N. Fedorova , Michael G. Zeitlin

We perform a first global exploration of the Constrained Next-to-Minimal Supersymmetric Standard Model using Bayesian statistics. We derive several global features of the model and find that, in some contrast to initial expectations, they…

High Energy Physics - Phenomenology · Physics 2015-05-13 Daniel E. Lopez-Fogliani , Leszek Roszkowski , Roberto Ruiz de Austri , Tom A. Varley

An accurate treatment of electronic spectra in large systems with a technique such as time dependent density functional theory (TDDFT) is computationally challenging. Due to the Nyquist sampling theorem, direct real time simulations must be…

Materials Science · Physics 2024-01-17 Matthias Kick , Ezra Alexander , Anton Beiersdorfer , Troy Van Voorhis