Whatever happened with the footballs in the Colts-Economists* game, the explanation is far from clear. From the NYTimes:
...[S]ome academic and research physicists now concede that they made a crucial error in their initial calculations, using an equation called the ideal gas law.When that error is corrected, the amount of deflation predicted in moving from room temperature to a 50-degree field is roughly doubled.
When the football controversy arose, a number of physicists cited the ideal gas law, which many of them taught in introductory courses. But applying the equation to real situations can be surprisingly deceptive. When a gauge indicates that the ball contains 12.5 p.s.i. — the minimum allowed by the N.F.L. — the actual pressure is more than twice that amount because the surrounding pressure of the atmosphere must be considered. [EE Digression: so much for the complaint about economists' misusing models with unrealistic assumptions; it happens everywhere and this example cries out for more caution in all fields.]
This roughly doubles how much a dip in temperature can lower the pressure. During a phone conversation, even Tegmark, the M.I.T. professor, initially used the lower value until recognizing the mistake. “I stand corrected,” he said...
There are still questions about why the Colts balls were NOT deflated. But the explanations offered in this article at least raise some important questions about whether the Economists cheated.
Let me re-emphasize the methodological point made in my above digression: We all use unrealistic assumptions to simplify analysis, no matter what field we are in. Understanding when which assumptions matter is part of the sophistication required for using the models.
*Note: I refer to the New England football team as "The Economists" because at one time a number of years ago, their coach, Bill Belichick, said that having been an economics major had helped him understand resource allocation and constrained choice better as coach.