= Classical path
{title2=$q_c(t)$}
A <classical path> joining prescribed endpoints is a stationary point of the <action>, satisfying the <Euler-Lagrange equation> and the endpoint <boundary conditions>. Expanding the <path integral> about each such path separates its classical phase from its quadratic fluctuation determinant. There may be multiple classical paths or none within a chosen real saddle class; the <semiclassical propagator> must respect that saddle structure rather than assuming a unique trajectory for every potential.
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