The physics of why hot water sometimes freezes faster than cold water
Once upon a generation ago, I worked at an ice rink. "Cleaning the ice" using an ice resurfacer involves cutting the top 1/16" of ice off and laying down new water. Hot water is preferred because it freezes faster and produces a denser sheet of ice; a denser sheet of ice is going to be better for skating.<p>It's nice to see more papers on it.