
Previously on
The Big Bang Theory:
The Big Bang Theory Season 5, Episode 24

...and you can't prove string THEORY.
The Big Bang Theory Season 1, Episode 3

...in deriving a grand unified THEORY.
The Big Bang Theory Season 4, Episode 3

Thank you for your notes on my paper
disproving quantum-brain-dynamic THEORY.
The Big Bang Theory Season 3, Episode 11

to get confirmation
for our THEORY.
The Big Bang Theory Season 12, Episode 13