Time-Dependent Circular Billiard

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</svg> and (a) <svg height="15.1375" id="M68" style="vertical-align:-3.3907pt" version="1.1" viewbox="0 0 58.325001 15.1375" width="58.325001" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>, illustrating reconnection.</table>

Mathematical Problems in Engineering

Time-Dependent Circular Billiard

Figure 3