the calculation
of nuclear MATRIX elements.
The Big Bang Theory Season 7, Episode 20
...he said that Johnny Depp
was in The Matrix.
The Big Bang Theory Season 6, Episode 6
You can see the MATRIX, can't you?
The Big Bang Theory Season 1, Episode 12
I haven't seen him this stuck since he
tried to figure out the third Matrix movie.
The Big Bang Theory Season 3, Episode 14