...from a friendly conversation with a friend, a mathematically unlearned mathematician, about the Poincaré theorem:
PR: If it’s quite simple, imagine that a rubber blade can be pulled onto a ball, and not onto a bubble.
I: I would have pushed...
During the drinking of alcoholic beverages in the kitchen, Nikolai Valuev proved to Grigory Perelman that the rubber heater is stretched onto the cupboard, bottle and Perelman's head, and the universe is more like a bowl twisted into a pipe.