: Renowned physicist Brian Greene appears as himself, giving a book reading that Sheldon and Amy attend specifically to heckle.
: The engagement is particularly devastating for Raj, who had been harboring a secret crush on Bernadette and was hoping the breakup rumor was true. Key Episode Details
In the The Big Bang Theory episode (Season 4, Episode 20), the plot centers on a social experiment conducted by Sheldon and Amy to test the speed and "virulence" of gossip within their friend group. Plot Summary
: As expected, the "juicy" rumor spreads like wildfire through the group, while the herb garden news is completely ignored.