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Related papers: Non-linearity and Non-Gaussianity through Phase In…

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Quantum non-Gaussianity is a key resource for quantum advantage in continuous-variable systems. We introduce a general framework to quantify non-Gaussianity based on correlation generation: two copies of a state become correlated at a…

Quantum Physics · Physics 2025-08-28 Oliver Hahn , Ryuji Takagi

In recent work we developed a description of cosmic large scale structure formation in terms of non-equilibrium ensembles of classical particles, with time evolution obtained in the framework of a statistical field theory. In these works,…

Statistical Mechanics · Physics 2018-04-27 Felix Fabis , Elena Kozlikin , Robert Lilow , Matthias Bartelmann

Brightness-temperature fluctuations in the redshifted 21-cm background from the cosmic dark ages are generated by irregularities in the gas-density distribution and can then be used to determine the statistical properties of density…

Astrophysics · Physics 2008-11-26 Annalisa Pillepich , Cristiano Porciani , Sabino Matarrese

We study the conditions under which thermal fluctuations generated in the contracting phase of a non-singular bouncing cosmology can lead to a scale-invariant spectrum of cosmological fluctuations at late times in the expanding phase. We…

High Energy Physics - Theory · Physics 2009-08-05 Yi-Fu Cai , Wei Xue , Robert Brandenberger , Xinmin Zhang

We establish for the first time heuristic correlations between harmonic space phase information and higher order statistics. Using the spherical full-sky maps of the cosmic microwave background as an example we demonstrate that known phase…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 H. I. Modest , C. Räth , A. J. Banday , K. M. Górski , G. E. Morfill

The pseudo-spectral method is proposed for following the evolution of density and velocity fluctuations at the weakly non-linear stage in the expanding universe with a good accuracy. In this method, the evolution of density and velocity…

Astrophysics · Physics 2017-02-01 Naoteru Gouda

Gaussianity is the very base for derivation of the cosmological parameters from the CMB angular power spectrum. Non-Gaussian signal, whether originated from experimental error or primordial source, could mimic extra power in the power…

Astrophysics · Physics 2009-11-11 Pavel Naselsky , Lung-Yih Chiang , Poul Olesen , Igor Novikov

I review several issues related to statistical description of gravitating systems in both static and expanding backgrounds. After briefly reviewing the results for the static background, I concentrate on gravitational clustering of…

Astrophysics · Physics 2009-02-16 T. Padmanabhan

I review the standard paradigm for understanding the formation and evolution of cosmic structure, based on the gravitational instability of dark matter, but many variations on this basic theme are viable. Despite the great progress that has…

Astrophysics · Physics 2007-05-23 Peter Coles

In this study, we explore the back reaction of phase transitions in the spectator sector on the inflaton field during slow-roll inflation. Due to the significant excursion of the inflaton field, these phase transitions are likely to occur…

High Energy Physics - Phenomenology · Physics 2024-11-20 Haipeng An , Qi Chen , Yuhang Li , Yuan Yin

As the quality of cosmological data continue to improve, it is natural to test the statistics of primordial fluctuations: are they Gaussian or non-Gaussian? I review a model which generates non-Gaussian adiabatic fluctuations from…

Astrophysics · Physics 2009-10-31 D. S. Salopek

We present the experimental investigation of the non-Gaussian nature of some mixtures of Fock states by reconstructing their Wigner function and exploiting two recently introduced measures of non-Gaussianity. In particular, we demonstrate…

Quantum Physics · Physics 2013-02-11 Alessia Allevi , Stefano Olivares , Maria Bondani

In the standard picture of cosmological structure formation, the Universe we see today is evolved under the gravitational instability from tiny random fluctuations. In this talk I discuss the onset of non-linearity in the large scale…

Astrophysics · Physics 2007-05-23 Lung-Yih Chiang

We probe the statistical nature of the primordial density field by measuring correlations between the power in adjacent Fourier modes. For certain types of non-Gaussian field, these k-space correlations would be expected to be more extended…

Astrophysics · Physics 2016-06-08 A. J. Stirling , J. A. Peacock

Using the quantum information picture to describe the early universe as a time dependent quantum density matrix, with time playing the role of a stochastic variable, we compute the non-gaussian features in the distribution of primordial…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-19 Cesar Gomez , Raul Jimenez

This article addresses some issues related to statistical description of gravitating systems in an expanding backgrounds. In particular, I describe (a) how the non linear mode-mode coupling transfers power from one scale to another in the…

Astrophysics · Physics 2009-11-13 T. Padmanabhan

Gaussian cosmic microwave background skies are fully specified by the power spectrum. The conventional method of characterizing non-Gaussian skies is to evaluate higher order moments, the n-point functions and their Fourier transforms. We…

Astrophysics · Physics 2011-05-10 Pedro G. Ferreira , Joao Magueijo

Non-Gaussian diffusion is commonly considered as a result of fluctuating diffusivity, which is correlated in time or in space or both. In this work, we investigate the non-Gaussian diffusion in static disordered media via a quenched trap…

Statistical Mechanics · Physics 2018-04-25 Liang Luo , Ming Yi

We present N-body cosmological numerical simulations including a primordial non-Gaussianity in the density fluctuation field quantified by the non-linear parameter $f_{NL}$. We have used MPGRAFIC code to produce initial conditions and the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 F. Fraschetti , J. M. Alimi , J. Courtin , P. S. Corasaniti

In this paper, we are interested to focus on the critical periods in the economy which are characterized by large fluctuations in macroeconomic indicators. To capture unusual and large fluctuations of inflation and unemployment, we…

Statistical Finance · Quantitative Finance 2021-02-03 Z. Koohi Lai , A. Namaki , A. Hosseiny , G. R. Jafari , M. Ausloos