English
Related papers

Related papers: Curvature Diffusions in General Relativity

200 papers

Diffusion in an evolving environment is studied by continuos-time Monte Carlo simulations. Diffusion is modelled by continuos-time random walkers on a lattice, in a dynamic environment provided by bubbles between two one-dimensional…

Soft Condensed Matter · Physics 2010-11-22 Janne Juntunen , Juha Merikoski

Most of the physically based techniques for rendering translucent objects use the diffusion theory of light scattering in turbid media. The widely used dipole diffusion model (Jensen et al. 2001) applies the diffusion-theory formula derived…

Graphics · Computer Science 2010-11-16 Konstantin Kolchin

We study a relativistic diffusion equation on the Riemannian phase space defined by Franchi and Le Jan. We discuss stochastic Ito (Langevin) differential equations (defining the diffusion) as a perturbation by noise of the geodesic…

General Relativity and Quantum Cosmology · Physics 2015-05-14 Z. Haba

We study families of smooth immersed regular planar curves $ \alpha : \left [-1,1 \right ]\times \left [0,T \right )\to \mathbb{R}^{2}$ satisfying the fourth order nonlinear curve diffusion flow with generalised Neumann boundary conditions…

Analysis of PDEs · Mathematics 2024-01-01 Mashniah Gazwani , James McCoy

We formulate Lorentz covariance of a quantum field theory in terms of covariance of time-ordered products (or other Green's functions). This formulation of Lorentz covariance implies spacelike local commutativity or anticommutativity of…

High Energy Physics - Theory · Physics 2009-11-10 O. W. Greenberg

The Lorentz gas, a point particle making mirror-like reflections from an extended collection of scatterers, has been a useful model of deterministic diffusion and related statistical properties for over a century. This survey summarises…

Chaotic Dynamics · Physics 2017-06-29 Carl P. Dettmann

We determine the long-time asymptotic behavior of a relativistic diffusion taking values in the unitary tangent bundle of a Robertson-Walker space-time. We prove in particular that when approaching the explosion time of the diffusion, its…

Probability · Mathematics 2014-05-02 Jürgen Angst

We construct a theory of particles moving in curved both momentum space and spacetime, being a generalization of Relative Locality. We find that in order to construct such theory, with desired symmetries, including the general coordinate…

General Relativity and Quantum Cosmology · Physics 2014-03-05 Francesco Cianfrani , Jerzy Kowalski-Glikman , Giacomo Rosati

Diffusion-driven patterns appear on curved surfaces in many settings, initiated by unstable modes of an underlying Laplacian operator. On a flat surface or perfect sphere, the patterns are degenerate, reflecting translational/rotational…

Soft Condensed Matter · Physics 2025-09-09 John R. Frank , Jemal Guven , Mehran Kardar , Leyna Shackleton

We show that diffeomorphism invariance of the Maxwell and the Dirac-Hestenes equations implies the equivalence among different universe models such that if one has a linear connection with non-null torsion and/or curvature the others have…

Mathematical Physics · Physics 2008-07-11 Roldao da Rocha , Waldyr A. Rodrigues

The Nelson stochastic mechanics of inhomogeneous quantum diffusion in flat spacetime with a tensor of diffusion can be described as a homogeneous one in a Riemannian manifold where this tensor of diffusion plays the role of a metric tensor.…

High Energy Physics - Theory · Physics 2012-10-09 Zahid Zakir

We study the diffusion phenomena on the negatively curved surface made up of congruent heptagons. Unlike the usual two-dimensional plane, this structure makes the boundary increase exponentially with the distance from the center, and hence…

Statistical Mechanics · Physics 2008-07-15 Seung Ki Baek , Su Do Yi , Beom Jun Kim

We define and study a family of distributions with domain complete Riemannian manifold. They are obtained by projection onto a fixed tangent space via the inverse exponential map. This construction is a popular choice in the literature for…

Statistics Theory · Mathematics 2008-05-07 Nikolay H. Balov

The covariant understanding of dispersion relations as level sets of Hamilton functions on phase space enables us to derive the most general dispersion relation compatible with homogeneous and isotropic spacetimes. We use this concept to…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Leonardo Barcaroli , Lukas K. Brunkhorst , Giulia Gubitosi , Niccoló Loret , Christian Pfeifer

We obtain a non-linear generalization of the relativistic diffusion of particles with spin. We discuss diffusion equations whose non-linearity is a consequence of quantum statistics. We show that the assumptions of the relativistic…

High Energy Physics - Theory · Physics 2011-06-20 Z. Haba

Inhomogeneous Nelson's diffusion in flat spacetime with a tensor of diffusion can be described as a homogeneous one in a Riemannian manifold with this tensor of diffusion as a metric tensor. The influence of matter to the energy density of…

General Relativity and Quantum Cosmology · Physics 2012-10-09 Zahid Zakir

Propagation of a particle accelerated by an external field through a scattering medium is studied within the generalized Lorentz model allowing inelastic collisions. Energy losses at collisions are proportional to $(1-\alpha^{2})$, where…

Statistical Mechanics · Physics 2015-06-25 Ph. A. Martin , J. Piasecki

The Lorentz covariant theory of propagation of light in the (weak) gravitational fields of N-body systems consisting of arbitrarily moving point-like bodies with constant masses is constructed. The theory is based on the Lienard-Wiechert…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sergei M. Kopeikin , Gerhard Schafer

Admitting the validity of Lorentz transformations for the space as time coordinates of the same event we derive their differential form in order to underline the correct prerequisites for the application of time and length contraction or…

General Physics · Physics 2008-12-02 Stefan Popescu , Bernhard Rothenstein

In this paper, we study the Einstein warped products and multiply warped products with a quarter-symmetric connection. We also study warped products and multiply warped products with a quarter-symmetric connection with constant scalar…

Differential Geometry · Mathematics 2014-10-02 Quan Qu , Yong Wang