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720 Ollie

|< < Prev #3264 (June 26, 2026)

Title text: This discovery was key to his demonstration of regular/goofy symmetry violation, which won him gold in the theory portion of the X Games.

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Explanation

Tony Hawk tells Cueball that doing a single 360-degree spin causes him to land backward rather than forward. This is unexpected, since a 360-degree turn in the xy plane is a full revolution, meaning that it should return Tony Hawk to his original position. He further claims that doing a 720-degree spin causes him to land forward, which seems to imply that revolving 360*n degrees causes him to reverse orientation n times (so if n is even, then he returns to the same orientation, and if n is odd, he lands with the opposite orientation).

The caption reveals that this is because Tony Hawk is a spin-½ fermion. This explains the paradox, but is unusual because spin-½ particles are normally very small, only occurring in quantum physics rather than Newtonian physics. Since Tony Hawk is not a subatomic particle,^{[citation needed]} it is unclear how his skateboard tricks could be described only by quantum physics.

A fermion is a classification of particles (or groups of particles) whose intrinsic angular momentum (aka "spin") is half-integer multiple of the reduced Planck constant, the behavior of these object's spin is described via spinors, a type of complex vector. This is in contrast to bosons, whose spin is an integer multiple of the reduced Planck constant, and described by the normal Euclidean vectors you know and love. ^{[citation needed]}

Transcript

Tony Hawk [holding a skateboard]: Something weird I've noticed is that if I do a 360 ollie, I land backward. I have to do a 720 to land going forward.

[An illustration, above the heads of Tony Hawk and Cueball, depicts Tony Hawk doing two 360-degree turns on a skateboard]

Caption: Tony Hawk discovers that he's a spin-½ fermion.

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