General Relativity cheat sheet

These notes provide a compact overview of the mathematical framework and core equations of general relativity. Starting from the basic notions of vector spaces, dual spaces, and tensors, the document progressively introduces metrics, covariant derivatives, and curvature tensors. The key geometrical objects of the theory - the Riemann tensor, Ricci tensor, and Einstein tensor - are summarized together with their role in the Einstein field equations. The presentation is organized as a structured reference sheet intended to facilitate quick review of the main definitions, identities, and formulas used in general relativity.