Adiabatic confinement and escape in an open billiard
Abstract
We introduce a stationary, field-free billiard that reproduces the adiabatic confinement mechanism of a magnetic mirror through boundary geometry alone. Rapid transverse reflections generate an approximately conserved action that plays the role of the magnetic moment, producing an effective longitudinal barrier and a nominal loss cone for escape. For the half-width profile considered here, confinement is controlled by a competition between mirror strength and adiabaticity: shortening the profile increases the mirror ratio but also reduces the accuracy of the adiabatic approximation. As a result, the escaping fraction is nonmonotonic and confinement is strongest at an intermediate profile length. We characterize the associated phase-space structure, escape-time statistics, and escape basins, revealing long-lived transient motion and a strong sensitivity of the final escape direction to the initial condition that persists as the uncertainty in the initial condition is reduced.
Related
- Adiabatic confinement and number-theoretic spectra of massless Dirac fermions in twisted trilayer graphene
- Confinement Geometry Regulates Fluctuations, Densities, and Collective Escape in Interacting Active Matter
- Lost in k-Space: An Open-Source MR-Physics Escape Room
- Spectral repulsion does not uniquely determine modal exchange in a deformed microwave billiard
- Geometry-induced chaos and scaling near two singular limits of an eye-shaped billiard
BibTeX
@misc{sales2026adiabatic,
title = {{Adiabatic confinement and escape in an open billiard}},
author = {Matheus Rolim Sales and Leonardo Costa de Souza and Ricardo Luiz Viana and Edson Denis Leonel and Iberê Luiz Caldas},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.07281},
eprint = {2610.07281},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.07281},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Adiabatic confinement and escape in an open billiard
AU - Matheus Rolim Sales
AU - Leonardo Costa de Souza
AU - Ricardo Luiz Viana
AU - Edson Denis Leonel
AU - Iberê Luiz Caldas
PY - 2026
DA - 2026/10/05
PB - arXiv
DO - 10.48550/arxiv.2610.07281
UR - https://arxiv.org/abs/2610.07281
AB - We introduce a stationary, field-free billiard that reproduces the adiabatic confinement mechanism of a magnetic mirror through boundary geometry alone. Rapid transverse reflections generate an approximately conserved action that plays the role of the magnetic moment, producing an effective longitudinal barrier and a nominal loss cone for escape. For the half-width profile considered here, confinement is controlled by a competition between mirror strength and adiabaticity: shortening the profile increases the mirror ratio but also reduces the accuracy of the adiabatic approximation. As a result, the escaping fraction is nonmonotonic and confinement is strongest at an intermediate profile length. We characterize the associated phase-space structure, escape-time statistics, and escape basins, revealing long-lived transient motion and a strong sensitivity of the final escape direction to the initial condition that persists as the uncertainty in the initial condition is reduced.
ER -