Open AccessIntroducing sub-Riemannian and sub-Finsler billiards
Author(s) -
Lucas Dahinden,
Álvaro del Pino
Publication year - 2022
Publication title -
discrete and continuous dynamical systems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.289
H-Index - 70
eISSN - 1553-5231
pISSN - 1078-0947
DOI - 10.3934/dcds.2022014
Subject(s) - symplectic geometry , context (archaeology) , euclidean geometry , reflection (computer programming) , boundary (topology) , mathematics , space (punctuation) , euclidean space , pure mathematics , geometry , mathematical analysis , computer science , paleontology , biology , programming language , operating system
We define billiards in the context of sub-Finsler Geometry. We provide symplectic and variational (or rather, control theoretical) descriptions of the problem and show that they coincide. We then discuss several phenomena in this setting, including the failure of the reflection law to be well-defined at singular points of the boundary distribution, the appearance of gliding and creeping orbits, and the behavior of reflections at wavefronts. We then study some concrete tables in \begin{document}$ 3 $\end{document} -dimensional euclidean space endowed with the standard contact structure. These can be interpreted as planar magnetic billiards, of varying magnetic strength, for which the magnetic strength may change under reflection. For each table we provide various results regarding periodic trajectories, gliding orbits, and creeping orbits.