Abstract
We consider the motion of a particle along the geodesic lines of the Poincaré half-plane. The particle is specularly reflected when it hits randomly-distributed obstacles that are assumed to be motionless. This is the hyperbolic version of the well-known Lorentz Process studied in the Euclidean context. We analyse the limit in which the density of the obstacles increases to infinity and the size of each obstacle vanishes: under a suitable scaling, we prove that our process converges to a Markovian process, namely a random flight on the hyperbolic manifold.
Similar content being viewed by others
Notes
We omit the calculations for sake of brevity. \(\mathcal {M} _{(q,v)}\) depends on (q, v) as parameters; for simplicity we will use the notation \(\mathcal {M}\) in the following.
Since \(\mathcal {M}\) preserve distances, it sends circumferences into circumferences.
References
Basile, G., Nota, A., Pulvirenti, M.: A diffusion limit for a test particle in a random distribution of scatterers. J. Stat. Phys. 155, 1087–1111 (2014)
Basile, G., Nota, A., Pezzotti, F., Pulvirenti, M.: Derivation of the Fick’s Law for the Lorentz model in a low density regime. Commun. Math. Phys. 336, 1607–1636 (2015)
Boldrighini, C., Bunimovitch, C., Sinai, Ya.G.: On the Boltzmann equation for the Lorentz gas. J. Stat. Phys. 32, 477–501 (1983)
Bonahon, F.: Low-Dimensional Geometry: From Euclidean Surfaces to Hyperbolic Knots, vol. 49. Student Mathematical Library, New Jersey (2009)
Cammarota, V., Orsingher, E.: Cascades of particles moving at finite velocity in hyperbolic spaces. J. Stat. Phys. 133, 1137–1159 (2008)
Cammarota, V., Orsingher, E.: Travelling randomly on the Poincaré half-plane with a Pythagorean compass. J. Stat. Phys. 130, 455–482 (2008)
Cammarota, V., Orsingher, E.: Hitting spheres on hyperbolic space. Theory Probab. Appl. 57(3), 560–587 (2012)
Desvillettes, L., Ricci, V.: The Boltzmann–Grad limit of a stochastic Lorentz gas in a force field. Bull. Inst. Math. Acad. Sin. (New Series) 2(2), 637–648 (2007)
Gallavotti, G.: Rigorous Theory of the Boltzmann Equation in the Lorentz Gas, Nota interna n. 358, Istituto di Fisica, Universitá di Roma (1972). http://ipparco.roma1.infn.it/pagine/deposito/1967-1979/041-bz
Gallavotti, G.: Statistical Mechanics. A Short Treatise. Springer, Berlin (1999)
Kelbert, M., Suhov, Yu.M: Branching Diffusions on \(H^d\) with variable fission: the Hausdorff dimension of the limiting set. Theory Probab. Appl. 51(1), 155–167 (2007)
Kolokoltsov, V.: Markov Processes, Semigroups and Generators. De Gruyter, Berlin (2011)
Orsingher, E.: Shot Noise Fields on the Sphere, Bollettino U.M.I., Series VI, vol. 8, pp. 477–496 (1984)
Orsingher, E., De Gregorio, A.: Random motions at finite velocity in a non-euclidean space. Adv. Appl. Probab. 39(2), 588–611 (2007)
Pinsky, M.A.: Isotropic transport process on a Riemannian manifold. Trans. Am. Math. Soc. 218, 353–360 (1976)
Spohn, H.: The Lorentz process converges to a random flight. Commun. Math. Phys. 60, 277–290 (1978)
Acknowledgments
We wish to thank the referees for the appreciation of our work and for the useful remarks. We also thank Dr. Alberto Di Iorio for drawing the pictures of this paper.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Orsingher, E., Ricciuti, C. & Sisti, F. Motion Among Random Obstacles on a Hyperbolic Space. J Stat Phys 162, 869–886 (2016). https://doi.org/10.1007/s10955-016-1450-y
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10955-016-1450-y
Keywords
- Poisson random fields
- Hyperbolic spaces
- Lorentz model
- Boltzmann–Grad limit
- Kinetic equations
- Random flights