A reality based independent journal of observation & analysis, serving the Flathead Valley & Montana since 2006. © James Conner.

21 January 2015

Tough guys, soft prolate spheroids, and a loose grip on the facts

Apparently, the New England Patriots played with under-inflated football in their win over the Indianapolis Colts last Sunday. According to various sources, 11 of 12 footballs were one or two pounds per square inch below the minimum in the league’s rulebook.

Two questions arise: (1) what happened, and (2) does the inflation rule, and the enforcement thereof, make sense?

What happened requires some experiments. I suspect the balls were inflated to the minimum in a warm room just before they were inspected. The air in the balls, having been compressed in the pump, probably was warmer than the room (but if they were filled from a tank of compressed gas, the gas would cool while expanding). The balls were inspected and approved. We don’t yet know whether each ball’s pressure was measured by a properly calibrated device. But we do know the league approved the balls for play.

A couple of hours later, the balls were moved to the field, where the weather was cold and wet. Most likely, the air in the balls cooled, became denser, filled less space, reducing the pressure. Verifying that requires some experiments. It’s a great lab project for physics and chemistry students at Harvard and MIT.

Does the inflation rule make sense? I have my doubts. A baseball is filled with a solid, not a gas. In cold weather it becomes hard and slick, making snapping off a curve more difficult, but it doesn’t shrink and there isn’t any way of softening it other than warming it.

A gas filled prolate spheroid is different. The leathery skin hardens and slickens in cold weather, becoming more and more rock like as the temperature drops. Inflated to specification, it’s much closer to obsidian than an inflated object on a 70°F late summer’s evening, harder to grip and control while throwing, harder to catch and hold while receiving.

Does this make sense? It doesn’t to me. Rather than requiring inflation pressures that harden the ball in cold weather, why not require measures of flexibility and gripability that make the ball easy to control across a wide range of temperatures? Why not abandon the narrow inflation targets, allowing lower inflation pressures during cold weather? If both teams could do it, neither would gain an advantage. But the aerial game might be better executed and more entertaining.

Finally, New England is innocent until proven guilty. And contrary to national sports writers who are ignorant of Boyle’s Law, and are fearfully willing to subordinate civil liberties to a good story, evidence of past misconduct is not evidence of current misconduct. We need facts, not hearsay and groundless speculation.