English
Related papers

Related papers: Post-collapse Lagrangian perturbation theory in th…

200 papers

We argue that a natural explanation for a variety of robust galaxy scaling relations comes from the perspective of pattern formation and self-organization as a result of symmetry breaking. We propose a simple Lagrangian model that combines…

Astrophysics of Galaxies · Physics 2021-08-04 Shankar C. Venkataramani , Alan C. Newell

Gravitational-collapse-based explanations of the cosmic web lead to problems in estimating the total mass in the universe. A first-principles several-scales model is developed here for the structural organisation of cosmic matter in a flat…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-11 Raphael Blumenfeld

A consistent guiding-center Hamiltonian theory is derived by Lie-transform perturbation method, with terms up to second order in magnetic-field nonuniformity. Consistency is demonstrated by showing that the guiding-center transformation…

Plasma Physics · Physics 2015-12-09 Natalia Tronko , Alain Brizard

We present a general formalism for identifying the caustic structure of an evolving mass distribution in an arbitrary dimensional space. For the class of Hamiltonian fluids the identification corresponds to the classification of…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Job Feldbrugge , Rien van de Weygaert , Johan Hidding , Joost Feldbrugge

In this paper we review a recently developed approximate method for investigation of dynamics of compressible ellipsoidal figures. Collapse and subsequent behaviour are described by a system of ordinary differential equations for time…

General Relativity and Quantum Cosmology · Physics 2015-08-03 G. S. Bisnovatyi-Kogan , O. Yu. Tsupko

The macroscopic effects of the quantum conformal anomaly are evaluated in a simplified two-dimensional model of gravitational collapse. The effective action and stress tensor of the anomaly can be expressed in a local quadratic form by the…

General Relativity and Quantum Cosmology · Physics 2023-09-08 Emil Mottola , Mani Chandra , Gian Mario Manca , Evgeny Sorkin

The large-scale matter distribution in the late-time Universe exhibits gravity-induced non-Gaussianity, and the bispectrum, three-point cumulant is expected to contain significant cosmological information. In particular, the measurement of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-06 Ichihiko Hashimoto , Yann Rasera , Atsushi Taruya

The formalism to compute the geometrical and topological one-point statistics of mildly non-Gaussian 2D and 3D cosmological fields is developed. Leveraging the isotropy of the target statistics, the Gram-Charlier expansion is reformulated…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Christophe Gay , Christophe Pichon , Dmitri Pogosyan

We present a new analytic approach to describe large scale structure formation in the mildly non-linear regime. The central object of the method is the time-dependent probability distribution function generating correlators of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-09 Diego Blas , Mathias Garny , Mikhail M. Ivanov , Sergey Sibiryakov

We analyzed the performance of a perturbation theory for nonlinear cosmological dynamics, based on the Lagrangian description of hydrodynamics. In our previous paper, we solved hydrodynamic equations for a self-gravitating fluid with…

Astrophysics · Physics 2009-11-10 Takayuki Tatekawa

The present paper derives the post-Newtonian Lagrangian of translational motion of N arbitrary-structured bodies with all mass and spin multipoles in a scalar-tensor theory of gravity. The multipoles depend on time and evolve in accordance…

General Relativity and Quantum Cosmology · Physics 2020-07-21 Sergei M. Kopeikin

We investigate the principles of quantum field theory using a stiff de Sitter space. We demonstrate that a non-unitary Lagrangian on a Euclidean AdS geometry can produce the perturbative expansion of late-time correlation functions to all…

High Energy Physics - Theory · Physics 2026-03-05 Sayantan Choudhury

Non-spherical dynamical approximations and models for the gravitational collapse are used to extend the well-known Press \& Schechter (PS) approach, in order to determine analytical expressions for the mass function of cosmic structures.…

Astrophysics · Physics 2009-09-25 Pierluigi Monaco

The collapse of thin dust shells in 2+1 dimensional gravity with and without a cosmological constant in analyzed. A critical value of the shell's mass as a function of its radius and position is derived. For $\Lambda < 0$, a naked…

General Relativity and Quantum Cosmology · Physics 2009-12-30 Yoav Peleg , Alan Steif

The statistical tools needed to obtain a mass function from realistic collapse time estimates are presented. Collapse dynamics has been dealt with in paper I of this series by means of the powerful Lagrangian perturbation theory and the…

Astrophysics · Physics 2015-06-24 Pierluigi Monaco

In this paper we study the evolution of a spherical matter overdensity in the context of the recently introduced Galileon field theory. Our analysis considers the complete covariant Lagrangian in four dimensions. This theory is composed by…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-20 Emilio Bellini , Nicola Bartolo , Sabino Matarrese

We present new perturbation theory (PT) predictions in the Spherical Collapse (SC) model for the 2-point moments of the large-scale distribution of dark matter density in the universe. We assume that these fluctuations grow under gravity…

Astrophysics · Physics 2009-11-07 E. Gaztanaga , P. Fosalba , R. A. C. Croft

In these lecture notes I review the theory of the non--linear evolution of cosmological perturbations in a self--gravitating collisionless medium, with vanishing vorticity. The problem is first analyzed in the context of the Newtonian…

Astrophysics · Physics 2015-06-24 Sabino Matarrese

Gravitational collapse of radiation shells in a non self-similar higher dimensional spherically symmetric spacetime is studied. Strong curvature naked singularities form for a highly inhomogeneous collapse, violating the cosmic censorship…

General Relativity and Quantum Cosmology · Physics 2009-11-07 S G Ghosh , R V Saraykar , A Beesham

Gravitationally collapsed objects are known to be biased tracers of an underlying density contrast. Using symmetry arguments, generalised biasing schemes have recently been developed to relate the halo density contrast $\delta_h$ with the…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-14 Dipak Munshi