The 11 Smartest People Who Have Appeared on The Big Bang Theory
Neil deGrasse Tyson - America's most famous astrophysicist Neil deGrasse Tyson appears in the Season 4 episode "The Apology Insufficiency."
Sheldon -- and many others IRL -- has beef with him because he famously demoted Pluto from planetary status to a mere rock floating in space (technically to "dwarf planet").
Bill Nye - The Science Guy appeared in the Season 7 episode "The Proton Displacement" as Sheldon's new TV scientist friend in an attempt to make Professor Proton jealous.
Bill Nye the Science Guy is fine and likable and uses his platform for good and all that, but he just seems too desperate for attention, you know?
Ira Flatow - Ira Flatow is public radio's most prominent science host.
George Smoot - Astrophysicist George Smoot is notable as the only person in history to win both a Nobel Prize and Are You Smarter Than A Fifth Grader?
Elon Musk - The visionary founder of SpaceX and Tesla appeared in Season 9's Thanksgiving episode, "The Platonic Permutation," volunteering with the gang at a soup kitchen.
Steve Wozniak - The co-founder of Apple appeared in the Season 4 episode "The Cruciferous Vegetable Amplification," in which he autographs Sheldon's ancient Apple II computer.
Danica McKellar - Danica McKellar didn't act much in the years after playing Winnie Cooper in The Wonder Years as she focused on her studies -- she earned a degree in mathematics from UCLA in 1998.
Stephen Hawking - Stephen Hawking sold 10 million copies of his book A Brief History of Time by making cosmology, the most mind-bending subject imaginable, digestible by the masses.
The Big Bang Theory airs Thursdays at 8/7c on CBS.