
No, he's a theoretical PHYSICIST
at CalTech.
The Big Bang Theory Season 9, Episode 8

Here, I am janitor.
In former Soviet Union, I am PHYSICIST.
The Big Bang Theory Season 1, Episode 13

Well, you're a PHYSICIST.
The Big Bang Theory Season 11, Episode 15

Leonard grew up to be
an experimental PHYSICIST.
The Big Bang Theory Season 1, Episode 16

...but I am, in fact,
a world-renowned PHYSICIST.
The Big Bang Theory Season 8, Episode 1