Corpus ID: 119126540

Unilluminable rooms, billiards with hidden sets, and Bunimovich mushrooms

  title={Unilluminable rooms, billiards with hidden sets, and Bunimovich mushrooms},
  author={P. Castle},
  journal={arXiv: Dynamical Systems},
  • P. Castle
  • Published 2017
  • Mathematics
  • arXiv: Dynamical Systems
The illumination problem is a popular topic in recreational mathematics: In a mirrored room, is every region illuminable from every point in the region? So-called \enquote{unilluminable rooms} are related to \enquote{trapped sets} in inverse scattering, and to billiards with divided phase space in dynamical systems. In each case, a billiard with a semi-ellipse has always been put forward as the standard counterexample: namely the Penrose room, the Livshits billiard, and the Bunimovich mushroom… Expand
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