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  • When people talk about the physics of American football, they normally mention force, torque,

  • and so onLike how the energy from two linemen colliding is enough to power a 60W

  • light bulb for over a minute, or is equivalent to an average person falling two stories off

  • of a building!

  • But there's another aspect of physics in football that isn't talked about as muchsymmetry!

  • You might think symmetry is just for butterflies and rorschach tests, but it's all over the

  • place in football: there's translational symmetry when teams keep the same formations as they

  • move up or down the field, and rotational symmetry when they switch sides after a touchdown.

  • Even the ball has axial symmetry so it can spin smoothly through the air.

  • But why is symmetry useful in the first place? Symmetry makes things easier, or at least

  • more efficient; it gives you a guide: "same scenario, same action." That means you don't

  • have to reinvent the wheel all the time: to draw a straight line, you just keep drawing

  • in the same direction. For a circle, keep curving the same amount.

  • So when football players practice a play over and over, the patterns of football become

  • so ingrained in their reflexes they can act without thinking. Psychologists call this

  • "habit formation"; we call it "symmetry in time"! And when players line up on the field

  • the same way at the thirty, or forty, or fifty yard lines, that's "symmetry in space".

  • Even physics itself is symmetricever heard of Newton's law: "a body in motion tends

  • to stay in motion"? That's just nature saying "keep doing the same thing." What's more,

  • Newton's laws of motion are the same now as they were yesterday, and they'll be the same

  • again tomorrow! Doesn't that make life easy?

  • Ultimately, symmetry is what allows both science AND football to function - if the laws of

  • the universe (or the rules of football) changed from day to day, we wouldn't be able to repeat

  • experiments, make predictions, or know what plays to practice.

  • So when you reach for yet another handful of chips while watching the next football

  • game, know that millions across the country are doing exactly the same, in perfect symmetry.

When people talk about the physics of American football, they normally mention force, torque,

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