She thought if I failed at THEORETICAL physics
that I should have a trade to fall back on.
The Big Bang Theory Season 2, Episode 10
It's very impressive.
For THEORETICAL work.
The Big Bang Theory Season 4, Episode 3
Now to tell you about
the Theoretical Physics Department...
The Big Bang Theory Season 2, Episode 6
- Well, yeah.
- I'm a THEORETICAL physicist.
The Big Bang Theory Season 1, Episode 15
So now let's bring out THEORETICAL physicist,
Dr. Sheldon Cooper!
The Big Bang Theory Season 6, Episode 18