English
Related papers

Related papers: An accurate fluid approximation for massive neutri…

200 papers

The quest for the neutrino mass is a central goal in contemporary cosmology, subject to intense scrutiny, and among different large-scale structure tracers the Lyman-Alpha forest is re-emerging as a unique tool to probe the neutrino mass at…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-23 Graziano Rossi

We develop a formalism to analytically describe the clustering of matter in the mildly non-linear regime in the presence of massive neutrinos. Neutrinos, whose free streaming wavenumber ($k_{\rm fs}$) is typically longer than the non-linear…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-24 Leonardo Senatore , Matias Zaldarriaga

We develop a highly accurate analytic approximation for small-scale non-cold relic perturbations by solving the collisionless Boltzmann equation in the quasi-stationary regime. The approximation is implemented in CLASSIER (CLASS Integral…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-20 Nanoom Lee , Yacine Ali-Haïmoud , Marc Kamionkowski

Cosmological neutrino mass and abundance measurements are reaching unprecedented precision. Testing their stability versus redshift and scale is a crucial issue, as it can serve as a guide for optimizing ongoing and future searches. Here,…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-13 Deng Wang , Olga Mena , Eleonora Di Valentino , Stefano Gariazzo

We study in detail how neutrino perturbations can be followed in linear theory by using only terms up to $l=2$ in the Boltzmann hierarchy. We provide a new approximation to the third moment and demonstrate that the neutrino power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 Maria Archidiacono , Steen Hannestad

We solve the Boltzmann equation for cosmological neutrinos around the epoch of the electron-positron annihilation in order to verify the freeze-out approximation and to compute accurately the cosmological neutrino distribution function. We…

Astrophysics · Physics 2009-10-30 Nickolay Y. Gnedin , Oleg Y. Gnedin

Future cosmological measurements should enable the sum of neutrino masses to be determined indirectly through their effects on the expansion rate of the Universe and the clustering of matter. We consider prospects for the gravitationally…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-30 Rupert Allison , Paul Caucal , Erminia Calabrese , Joanna Dunkley , Thibaut Louis

We present a new method for generating initial conditions for numerical cosmological simulations in which massive neutrinos are treated as an extra set of N-body (collisionless) particles. It allows us to accurately follow the density field…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Arka Banerjee , Devon Powell , Tom Abel , Francisco Villaescusa-Navarro

Massive neutrinos make up a fraction of the dark matter, but due to their large thermal velocities, cluster significantly less than cold dark matter (CDM) on small scales. An accurate theoretical modelling of their effect during the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-21 Yacine Ali-Haïmoud , Simeon Bird

Boltzmann codes are used extensively by several groups for constraining cosmological parameters with Cosmic Microwave Background and Large Scale Structure data. This activity is computationally expensive, since a typical project requires…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Diego Blas , Julien Lesgourgues , Thomas Tram

We present a novel, fast and precise method for including the effect of light neutrinos in cosmological N-body simulations. The effect of the neutrino component is included by using the linear theory neutrino perturbations in the…

Astrophysics · Physics 2010-04-15 Jacob Brandbyge , Steen Hannestad

Neutrino transport in spherically symmetric models of stellar core collapse and bounce has achieved a technically complete level, rewarded by the agreement among independent groups that a multi-dimensional treatment of the…

Astrophysics · Physics 2008-11-26 M. Liebendoerfer , U. -L. Pen , C. Thompson

Boltzmann solvers are an important tool for the computation of cosmological observables in the linear regime. In the presence of massive neutrinos, they involve solving the Boltzmann equation followed by an integration in momentum space to…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-22 Caio Bastos de Senna Nascimento

Constraining neutrino mass through cosmological observations relies on precise simulations to calibrate their effects on large scale structure, while these simulations must overcome computational challenges like dealing with large velocity…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-08 Bing-Hang Chen , Jun-Jie Zhao , Hao-Ran Yu , Yu Liu , Jian-Hua He , Yipeng Jing

We study the multi-dimensional properties of neutrino transfer inside supernova cores by solving the Boltzmann equations for neutrino distribution functions in genuinely six dimensional (6D) phase space. Adopting representative snapshots of…

High Energy Astrophysical Phenomena · Physics 2014-12-30 K. Sumiyoshi , T. Takiwaki , H. Matsufuru , S. Yamada

We propose a procedure to evaluate the impact of nonlinear couplings on the evolution of massive neutrino streams in the context of large-scale structure growth. Such streams can be described by general nonlinear conservation equations,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Hélène Dupuy , Francis Bernardeau

Effective field theory of dark matter fluid on large scales predicts the presence of viscosity of the order of $10^{-6} H_0 M_P^2$. It has been shown that this magnitude of viscosities can resolve the discordance between large scale…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Sampurn Anand , Prakrut Chaubal , Arindam Mazumdar , Subhendra Mohanty , Priyank Parashari

Complimenting recent work on the effective field theory of cosmological large scale structures, here we present detailed approximate analytical results and further pedagogical understanding of the method. We start from the collisionless…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-02 Mark P. Hertzberg

Cosmology in the near future promises a measurement of the sum of neutrino masses, a fundamental Standard Model parameter, as well as substantially-improved constraints on the dark energy. We use the shape of the BOSS redshift-space galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-09 Amol Upadhye

Massive neutrinos suppress the growth of cosmic structure on small, non-linear, scales. It is thus often proposed that using statistics beyond the power spectrum can tighten constraints on the neutrino mass by extracting additional…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-16 Adrian E. Bayer , Arka Banerjee , Uros Seljak