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Related papers: Hamiltonians for Compact Homogeneous Universes

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Recently a {\it local} true (completely gauge fixed) Hamiltonian for spherically symmetric collapse was derived in terms of Ashtekar variables. We show that such a local Hamiltonian follows directly from the geometrodynamics of gravity…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Jack Gegenberg , G. Kunstatter

A novel routine to investigate the scalar fields in a cosmological context is discussed in the framework of the Hamiltonian formalism. Starting from the Einstein-Hilbert action coupled to a Lagrangian density that contains two components -…

General Relativity and Quantum Cosmology · Physics 2013-09-16 Alex E. Bernardini , O. Bertolami

All classes of spatially homogeneous space-time models are found that allow the integration of the equations of motion of test particles and the eikonal equation by the method of complete separation of variables according to type (2.1).…

General Relativity and Quantum Cosmology · Physics 2020-08-26 Evgeny Osetrin , Konstantin Osetrin , Altair Filippov

We develop the Hamiltonian theory of axial perturbations around a general time-dependent spherical background spacetime. Using the fact that the linearized constraints are gauge generators, we isolate the physical and unconstrained axial…

General Relativity and Quantum Cosmology · Physics 2009-02-09 David Brizuela , Jose M. Martin-Garcia

The evolution of polar perturbations on a spherical background spacetime is analyzed. The matter content is assumed to be a massless scalar field.This provides a nontrivial dynamics to the background and the linearized equations of motion…

General Relativity and Quantum Cosmology · Physics 2022-01-28 David Brizuela

Dynamics generated from Hamiltonians enjoy potential pathways to quantisation, but standard Hamiltonians are only capable of generating conservative forces. Classes of Hamiltonians have been proposed in Berry et al. capable of generating…

Mathematical Physics · Physics 2024-06-28 Fredy Yip , A. C. H. Cheung

We present a general framework for analyzing spatially inhomogeneous cosmological dynamics. It employs Hubble-normalized scale-invariant variables which are defined within the orthonormal frame formalism, and leads to the formulation of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Claes Uggla , Henk van Elst , John Wainwright , George F R Ellis

In this work, we make new developments in generic cotangent bundle geometries, depending on all phase-space variables. In particular, we will focus on the so-called generalized Hamilton spaces, discussing how the main ingredients of this…

Mathematical Physics · Physics 2024-07-29 J. J. Relancio , L. Santamaría-Sanz

Here, we study quantitative homogenization of first-order convex Hamilton-Jacobi equations with $(u/\varepsilon)$-periodic Hamiltonians which typically appear in dislocation dynamics. Firstly, we establish the optimal convergence rate by…

Analysis of PDEs · Mathematics 2025-07-02 Hiroyoshi Mitake , Panrui Ni , Hung V. Tran

Recently, there has been an increasing interest in modelling and computation of physical systems with neural networks. Hamiltonian systems are an elegant and compact formalism in classical mechanics, where the dynamics is fully determined…

Numerical Analysis · Mathematics 2022-06-28 Elena Celledoni , Andrea Leone , Davide Murari , Brynjulf Owren

A covariant hamiltonian formalism for the dynamics of compact spinning bodies in curved space-time in the test-particle limit is described. The construction allows a large class of hamiltonians accounting for specific properties and…

General Relativity and Quantum Cosmology · Physics 2016-12-21 J. W. van Holten

The Hamiltonians of $SU(2)$ and $SU(3)$ gauge theories in 3+1 dimensions can be expressed in terms of gauge invariant spatial geometric variables, i.e., metrics, connections and curvature tensors which are simple local functions of the…

High Energy Physics - Theory · Physics 2009-10-28 Daniel Z. Freedman

A straightforward method to compute Hamilton's density for theories that are linear in the spacetime curvature is provided. It is shown that the lapse function and shift vector still give rise to primary constraints, while the induced…

General Relativity and Quantum Cosmology · Physics 2022-06-23 Yuri Bonder

A family of effective actions in Hamiltonian form is derived for a self-gravitating sphere of isotropic homogeneous dust. Starting from the Einstein-Hilbert action for barotropic perfect fluids and making use of the symmetry and equation of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Roberto Casadio

We consider the Hamiltonian dynamics of spherically symmetric Einstein gravity with a thin null-dust shell, under boundary conditions that fix the evolution of the spatial hypersurfaces at the two asymptotically flat infinities of a…

General Relativity and Quantum Cosmology · Physics 2016-08-25 Jorma Louko , Bernard F. Whiting , John L. Friedman

The Hamiltonian approach to the General Relativity is formulated as a joint nonlinear realization of conformal and affine symmetries by means of the Dirac scalar dilaton and the Maurer-Cartan forms. The dominance of the Casimir vacuum…

General Relativity and Quantum Cosmology · Physics 2015-05-30 V. N. Pervushin , A. B. Arbuzov , B. M. Barbashov , R. G. Nazmitdinov , A. Borowiec , K. N. Pichugin , A. F. Zakharov

Most classical mechanical systems are based on dynamical variables whose values are real numbers. Energy conservation is then guaranteed if the dynamical equations are phrased in terms of a Hamiltonian function, which then leads to…

Mathematical Physics · Physics 2013-12-05 Gerard 't Hooft

Recently a path integral formalism has been proposed by the author which gives the time evolution of moments of slow variables in a Hamiltonian statistical system. This closure relies on evaluating the informational discrepancy of a time…

Mathematical Physics · Physics 2015-10-23 Richard Kleeman

By considering the most general metric which can occur on a contractable two dimensional symplectic manifold, we find the most general Hamiltonians on a two dimensional phase space to which equivariant localization formulas for the…

High Energy Physics - Theory · Physics 2009-10-22 Richard J. Szabo , Gordon W. Semenoff

An algebraic procedure of getting of canonical variables in a rigid body dynamics is presented. The method is based on using a structure of an algebra of Lie-Poisson brackets with which a Hamiltonian dynamics is set. In a particular case of…

Chaotic Dynamics · Physics 2007-05-23 Alexander Pavlov