The Josh Groban paradox
Josh Groban, the singer/actor plays Walter Jr Bernard in The Office.
A few seasons earlier, the cast watches an episode of Glee, proving that Glee exists in The Office universe.
Josh Groban appears in Glee as Josh Groban, the singer/actor.
So... In the office universe, Josh Groban and Walter Jr Bernard both exist, therefore proving surely that cloning exists?
Same issue with Jim Carrey. Phyllis mentions him in Back From Vacation (go get his autograph!) Then he shows up in Search Committee as the finger lakes guy.
And the insolent pizza delivery boy.
Nah they just look alike. That's always my assumption when this occurs in-universe, like how one of the Ocean's movies had Julia Roberts playing a woman who coincidentally looked just like Julia Roberts. There are a lot of celebrity look-a-likes in the world, in the realm of fiction it isn't much of a stretch that two people on Earth could be easily confused for each other.
Hell, when Natalie Portman and Keira Knightley were making Star Wars Episode 1, they looked so similar that Knightley's mother couldn't tell them apart. And they're both actresses, so statistically speaking if there's another actress who looks that similar, there are probably dozens of other women who look close enough to be difficult to distinguish.
He is also in the Pawnee p&r universe.
Groban likes his ladies to pop
You think that’s bad? How about when Andy references Bradley Cooper in “Gettysburg” and then, the next season, Ed Helms disappears for a chunk of episodes to go shoot another Hangover movie with Bradley Cooper?