Feynman Lectures On Gravitation -

: The principle of equivalence, the necessity of a tensor field, and the iterative derivation of field equations.

The Feynman Lectures on Gravitation (1962–63) is a unique graduate-level exploration of general relativity that departs from traditional geometric interpretations. Instead of starting with curved spacetime, Feynman approaches gravity as a (the graviton) coupled to the energy-momentum tensor, demonstrating that Einstein’s equations are the inevitable result of this quantum field theory approach. Core Philosophical Approach Feynman Lectures on Gravitation

: Detailed discussions on planetary motion (including the perihelion shift of Mercury), gravitational waves, and the behavior of light in gravitational fields. : The principle of equivalence, the necessity of