
When Einstein came up
with special RELATIVITY...
The Big Bang Theory Season 3, Episode 14

Just explaining the theory of RELATIVITY.
The Big Bang Theory Season 6, Episode 5

Einstein's RELATIVITY equations
pop out.
The Big Bang Theory Season 11, Episode 13

...with general RELATIVITY
than does string theory.
The Big Bang Theory Season 2, Episode 2

...of the equations of general RELATIVITY
and hydrodynamics...
The Big Bang Theory Season 6, Episode 24