# Unilluminable rooms, billiards with hidden sets, and Bunimovich mushrooms

@article{Castle2017UnilluminableRB, title={Unilluminable rooms, billiards with hidden sets, and Bunimovich mushrooms}, author={P. Castle}, journal={arXiv: Dynamical Systems}, year={2017} }

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

#### One Citation

Optimal Illumination of Arbitrary Rooms Using Genetic Algorithm

- Computer Science
- 2019 8th International Conference on Information and Communication Technologies (ICICT)
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Genetic algorithm is used to explore exponential search space of lamps placement and find those that suit the given criteria and show promising arrangements of lamps that can be used in situations that require an emitter of signals in an obstruction filled environment. Expand

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