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
When Einstein came up
with special RELATIVITY...
The Big Bang Theory Season 3, Episode 14
The wheel was a great idea.
Relativity was a great idea.
The Big Bang Theory Season 1, Episode 7
...with general RELATIVITY
than does string theory.
The Big Bang Theory Season 2, Episode 2