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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° spin causes him to land backward rather than forward. This is unexpected, since a 360° turn in the xy plane is a full revolution, meaning that it should normally return Tony Hawk to his original position rather than perform a half-rotation (normally the result of a 180° spin). As repeating this would reverse his reverse, doubling this to a 720° spin is what finally allows him to land forward. Normally, revolving 360*n degrees, for any whole number (n=0, n=±1, n=±2, etc) should leave him pointing the same range as before, but for him he returns to the same orientation if n is even, but he lands with the opposite orientation if n is odd.

The caption reveals that this is because Tony Hawk is a spin-½ fermion. Spin-½ fermions have the unusual property that they must be rotated through two full turns before returning to their original configuration. 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 objects' 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]}

Tony Hawk is an American skateboarder credited with inventing the 720, a trick (under normal circumstances) involving two full mid-air rotations. Since Hawk invented it in 1985, larger mid-air rotations have been invented (up to 1260, three and a half rotations), and according to the comic they can have even stranger quantum properties.

The title text is a riff on the Nobel Prize-winning discovery of CP violation, (something that may have been on Randall's mind, recently, due to the prior comic's subject matter/anti-matter). The regular/goofy styles of riding a skateboard could be considered as a physical quality of the "skateboarder particle", as values of charge and parity are of subatomic ones. The X Games are a prestigious 'street-sport' event that includes competitions in skateboarding as well as other related board- and bike-disciplines. The parallel is made between being able to win a gold medal for impressive skateboarding skills (and demonstrating new tricks, in the process, as Tony Hawk has been known to do) and earning the gold Nobel Prize medal for a scientific achievements in Physics or one of the other established prize categories. So far, nobody has done both of these. But, if this comic is entirely true, perhaps Tony Hawk could be the first to do so.

"Goofy matter", and Tony Hawk's involvement in physics, is also the subject of 2967: Matter. Skateboarding is also the subject of 296: Tony Hawk.

Transcript

[Tony Hawk and Cueball are talking. Tony Hawk is holding his skateboard. An image, above the heads of Tony Hawk and Cueball, depicts Tony Hawk doing two 360-degree turns on a skateboard]

Tony Hawk: 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.

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

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