Why a Laser Beam Umbrella Wouldn’t Work
As part of their ongoing “What If?” series, Randall Munroe of xkcd and Henry Reich of MinutePhysics explain why an umbrella made out of laser beams could not work despite how cool it would be to vaporize rain as it fell from the sky.
Stopping rain from falling on something with an umbrella is boring. What if you tried to stop rain with a laser that targeted and vaporized each incoming droplet before it could come within ten feet of the ground?