Watch This Teenager Set the New Rubik's Cube Speed Record

The world record for least time spent solving a standard Rubik’s Cube is now officially under five seconds, thanks to 14-year-old Lucas Etter. He set the new record at 4.904 seconds this past Saturday at Clarksville, Maryland’s River Hill Fall competition. His speedy achievement has since been recognized by Guinness World Records and the World Cube Association.

Fellow teenager Collin Burns set the old record of 5.25 seconds during a World Cubing Association competition in Doylestown, Pennsylvania earlier this year. At the same event Etter attended this weekend, one of his competitors shaved .16 milliseconds off that time when he solved a Rubik’s Cube in 5.09 seconds. That time was never officially recognized as the new record, however, as Etter was able to best him before the day’s end.

While Etter is now recognized as the Rubik’s Cube record holder of the human world, the true distinction may arguably belong to a robot. In 2014, a “speedcuber” robot built from LEGO blocks was able to solve a cube in 3.253 seconds. It may take a while for humans to beat that record, but Etter can take comfort in knowing that he’s faster than at least one Rubik’s Cube-solving robot—and he only used two hands.

[h/t: The Verge]

This Spinning Arrow Might Make You Question Your Sense of Direction

'Round and 'round the arrow goes, but where it points—nobody knows. As spotted by Sploid, this befuddling optical illusion of a spinning arrow appears to be pointing right no matter how many 180-degree turns you give it. See for yourself:

Right Pointing Arrow: spin this arrow 180 degrees and it still points to the right- only in a mirror will it point left (and only to the left). Another incredible ambiguous object illusion by mathematician Kokichi Sugihara of Meiji University in Japan, the inventor of this illusion and art form. A clever combination of reflection, perspective, and viewing angle produce this striking illusion. ➡️ Follow the link in my profile for info about where to get this illusion arrow and other amazing items featured here on @physicsfun #illusion #ambiguouscylinderillusion #ambiguouscylinder #geometry #mirrorreflection #physics #ambiguousobject #kokichisugihara #physicstoy #math #mathtoy #mathstoy #optics #opticalillusion #3dprinting #perspective #science #scienceisawesome

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The illusion was designed by Kokichi Sugihara, a mathematics professor at Meiji University in Japan. Sugihara is adept at creating 3D objects that seem to defy the laws of physics, using a “combination of reflection, perspective, and viewing angle” to trick viewers, according to the physicsfun Instagram page, which posted the video.

The effect still works when the object is held up to a mirror, although instead of pointing right, the reflection shows the arrow pointing left each time. The object appears symmetrical when viewed from above, but when you look at it head-on, it appears to come to a point on one side. It all comes down to the way the edge is carved—a testament not only to Sugihara's mathematical ability, but also his craftiness.

Want to see more of Sugihara’s work? In another video, a rack of cylinders appears to be transformed into a rack of rectangles right before your eyes.

[h/t Sploid]

Name the U.S. State Names that Appear in Monopoly


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