
And, of course, it's Gravity Probe B.
The Big Bang Theory Season 1, Episode 13

Well, I have an extremely
low center of GRAVITY.
The Big Bang Theory Season 7, Episode 11

Yes, and he never unified GRAVITY
with the other forces.
The Big Bang Theory Season 4, Episode 22

The lack of GRAVITY did decompress my
spine, so I'm, like, an inch-and-a-half taller.
The Big Bang Theory Season 6, Episode 4

...for this university's
six-loop quantum GRAVITY calculations.
The Big Bang Theory Season 6, Episode 9