TV series example of the word
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now it's dark matter."
The Big Bang Theory Season 9, Episode 8
Um, it used to be string theory, now it's dark matter.

The Big Bang Theory Season 3, Episode 4
Ooh, dark matter. We better bring a flashlight, ha, ha.

The Big Bang Theory Season 12, Episode 18
Apparently, Halley's afraid of the dark now

The Big Bang Theory Season 8, Episode 6
You know the government funded the biggest experiment yet to detect dark matter?

Game of Thrones Season 3, Episode 1
And as my reward, I was trundled off to some dark little cell.