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# physics

## Basic idea

The study of matter, energy, space, and time. Modern physics rests on two incompatible pillars: general relativity (gravity at large scales) and quantum mechanics (matter at small scales).

## Key formulas

* Newton's second law: $F=ma$
* Mass-energy equivalence: $E=mc^2$
* Schrödinger equation: $i\hbar\partial\_t\psi = \hat H\psi$
* Einstein field equations: $G\_{\mu\nu}+\Lambda g\_{\mu\nu}=\dfrac{8\pi G}{c^4}T\_{\mu\nu}$