An infinite number of Sheldons still wouldn't dance
When Penny asks Sheldon to dance in "The Gothowitz Deviation," he uses the Many Worlds Theory to decline in the most overly-intelligent way possible:
"Penny, while I subscribe to the Many Worlds Theory, which posits the existence of an infinite number of Sheldons in an infinite number of universes, I assure you that in none of them am I dancing."
The Many Worlds Theory or Interpretation is a sub-genre of quantum mechanics that argues that we all exist in multiple, semi-connected worlds simultaneously. A simple "no" just isn't Sheldon's style.
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