Earthquake Early Warning: the P-Wave Race

Earthquake early-warning systems don't predict quakes — they win a race against physics. The fast but weak P-wave reaches a seismic station near the epicenter seconds before the slow, destructive S-wave reaches a distant city, and that gap is the only warning anyone gets. This simulation renders the rupture, the expanding P- and S-wave fronts, a monitoring station, and a city in 3D, then works the real travel-time arithmetic — t = distance / velocity for each wave, minus network processing delay — to show exactly how many seconds of lead time the physics allows, and how that window collapses to nothing inside the "blind zone" near the epicenter.