Physics Professors Tackle the NFL’s ‘Ballghazi’ Scandal

The National Football League’s “Ballghazi” scandal (also known as “Deflategate”) continues to threaten our national innocence, and some news media have turned to academe for answers.

After winning their conference-title game on Sunday, earning a place in the Super Bowl, the New England Patriots came under suspicion because 11 of the 12 footballs they supplied for the game were found to be underinflated two pounds per square inch below the league’s minimum standard, arguably making them easier to grip. The balls were reportedly inspected by referees before the game, but when tested during the game they were found to be below code.

The NFL is investigating the situation. In the meantime, speculation reigns. And some publications have called on physics professors to join in.

In an interview with, Martin Schmaltz, a physics professor at Boston University, floated a theory about how the Patriots’ balls might have passed inspection before the game but failed the midgame pressure test.

The key question, as outlined by Schmaltz, is where the balls were tested prior to the game. If the balls were tested indoors, where the temperature was likely above the 50 degree temperature outdoors Sunday, then the pressure inside the ball would drop once the ball is moved outdoors and begins to cool off.

“If they had inflated the balls inside the building and put it to the minimum amount, and then brought it outside to temperatures that were about 30 degrees lower, that would drop the PSI by between 1 and 2,” Schmaltz explained.

However, if the footballs were inflated, stored, and tested outdoors, said Mr. Schmaltz, then even extraordinary trauma at the hands of New England’s famous tight end would not explain the pressure drop.

Schmaltz also debunks Tom Brady’s claim that Rob Gronkowski can deflate a football by spiking it.

Ah, good to know.

The Boston Herald, meanwhile, turned to Michael J. Naughton, a professor and chair of the physics department at Boston College. He found it plausible that the Patriots’ balls could have become deflated without any tampering.

“If 11 of 12 footballs were deflated by two pounds, that is totally within the realm of the numbers that you would get in the equation. Weather will certainly deflate the footballs by a pound or two—but it all depends on the details.”

Fair enough, professor. But can someone get some data, please?

Enter Chad Orzel, an associate professor of physics at Union College, in Schenectady, N.Y., somewhat west of Patriots’ territory:

I got a couple of old footballs from Union College’s athletic department, pumped them up and popped them in the freezer. After a night in the cold, the pressure was around 2 psi lower, just like the Patriots’ footballs—from about 19 psi at the start (I slightly overinflated the balls by using the tire pump in my car) down to about 17 psi.

Of course, the temperature difference involved was a little extreme—from about 68F in my office, down to about -10F in the freezer. So, you can use temperature changes to produce the pressure change seen by investigators, but the temperature required would’ve matched the legendary Ice Bowl of 1967. Last Sunday’s game was played in pouring rain at about 50F, so unless they did the pre-game testing of the balls in a sauna, or the post-game investigation in a meat locker, thermodynamics alone can’t get the Patriots off the hook.

Mr. Orzel wasn’t the only physicist putting footballs in fridges in search of the truth. Dale Syphers, a physics professor at Bowdoin College (and a Patriots fan), ran a similar experiment for the local NBC affiliate:

The valve of the ball can’t take the stress of players getting tackled and falling on it. Air will seep out. [Mr. Syphers] also demonstrated how a change in temperature can cause the pressure to drop. He left one in the room and put the other in a refrigerator at 40 degrees. A half-hour later, the room-temperature ball was still 13 pounds, but the refrigerated was 11.7 pounds.

“If you’re doing it at 70 degrees, you’re playing with a ball that’s a different pressure, and especially if you have cold games down to 10 degrees, it can be 2 to 3 pounds lower,” he said.

If nothing else, these academics have supplied some useful rationalizations to Patriots fans as the nation waits for more details. In the meantime, at least one university office has tried to harness the hubbub for its own purposes.

Higher education to the rescue.

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