UCLA physics professor loses $10k bet about downwind kart

UCLA Physics professor Alex Kusenko saw YouTuber Veritasium's video of him riding in a wind-powered vehicle moving directly downwind faster than the wind and told Veritasium that "directly downwind faster than the wind" (DDWFTTW, as it's known in the wind kart world) is impossible.

They bet each other $10,000 and asked Neil DeGrasse Tyson and Bill Nye to witness the signing of the bet.

Veritasium was able to demonstrate that DDWFTTW is real and Kusenko paid the bet.