Penny has no interest
in SUBATOMIC particle research.
The Big Bang Theory Season 3, Episode 15
It's SUBATOMIC particles
in endless aimless collision.
Breaking Bad Season 3, Episode 10
...of a SUBATOMIC particle
called the Higgs boson.
The Big Bang Theory Season 6, Episode 3
Subatomic particles.
The Big Bang Theory Season 12, Episode 20
I can't see SUBATOMIC particles,
but nevertheless, they're there.
The Big Bang Theory Season 4, Episode 3