The moment you knew something was off

You are watching a clip on social media of a skateboarder landing an impossible trick. Something feels wrong. The arms swing a little too smoothly. The dust rises at just slightly the wrong pace. Within half a second, before you have consciously formed a thought, your brain has already delivered its verdict: this video has been slowed down .

That verdict came from somewhere. Not from a timestamp in the corner of the screen. Not from a caption. Something in the visual texture of the footage itself — the way motion blur smears across a wheel, the rhythm of a jacket flap, the relationship between how fast the body moves and how long it takes to land — told your nervous system that time in this clip is not moving at its natural rate.

For decades, this particular skill has been almost entirely off-limits for artificial intelligence.…