Symmetries and conservation laws

The first-variation identity, both Noether theorems and their converses, mechanics and gauge fields, the stationary black-hole first law, null Lagrangians, Euler covariance, and the reduction of Riemannian differential invariants to curvature.

1. Variational symmetries and Noether's first theorem
2. Infinite symmetry groups and Noether's second theorem
3. The formal calculus of variations and differential invariants

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