Riemannian Geometry of Grassmann Manifolds with a View on Algorithmic Computation
نویسندگان
چکیده
We give simple formulas for the canonical metric, gradient, Lie derivative, Riemannian connection, parallel translation, geodesics and distance on the Grassmann manifold of p-planes in Rn. In these formulas, p-planes are represented as the column space of n £ p matrices. The Newton method on abstract Riemannian manifolds proposed by S. T. Smith is made explicit on the Grassmann manifold. Two applications –computing an invariant subspace of a matrix and the mean of subspaces– are worked out.
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