A French physicist has won an Ig Nobel Prize for using mathematical formulas to determine whether cats are liquid or solid.

The Ig Nobel prizes are awarded every year by Improbable Research, an organization devoted to science and humor. The goal is to highlight scientific studies that first make people laugh, then think.

A ceremony is held every year at Harvard University.

Marc-Antoine Fardin was awarded the Ig Nobel Prize in physics for his research paper on the rheology of cats.

“At the center of the definition of a liquid is an action: A material must be able to modify its form to fit within a container,” Fardin said.

“If we take cats as our example, the fact is that they can adapt their shape to their container if we give them enough time. Cats are thus liquid if we give them the time to become liquid.”

In his official research paper, Fardin discusses many factors including relaxation time, experimental time, the type of container, and the cat’s degree of stress.

The conclusion? Cats can be either liquid or solid, depending on the circumstances, Fardin reported in the Rheology Bulletin in 2014.

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