The vector $T^a$ is the tangent to a reference member of a one-parameter family of affinely parametrized <geodesics>. The <Jacobi field> $Y^a$ is the infinitesimal connecting vector from that geodesic to a neighboring one at equal parameter. The <geodesic deviation> equation states that curvature determines their relative acceleration.

Solution

Past exam of the mathematics course of the University of Cambridge / 2023 / iii / Paper 309 / 1 / c / Solution

 Solution (source code)