Why you should wear a mask even though there’s practically no chance it will keep you from getting the coronavirus

TL;DR — the practice saves lives, even if not yours.

A risk that’s trivial for one person is a real concern when it’s suffered by 300,000,000 Americans.

How much modest personal discomfort and inconvenience is it worth, to save devastation somewhere else? Especially when you don’t know the people, don’t know where, and don’t even know for sure it’ll happen? People donate dollars and volunteer time when earthquakes and hurricanes strike. Standing in cold flood muck all night stacking sandbags by the river is pretty uncomfortable and inconvenient. Masks are a lot easier.

Continue reading “Why you should wear a mask even though there’s practically no chance it will keep you from getting the coronavirus”

Sophomoric MIT student laser work

As undergrads in the late fall of 1969, John and I were both taking an optics course, six point something or other. It required a lab project. Perhaps primed by Star Trek and Mission Impossible, we ambitiously decided to build a long-distance laser communicator.

There was clear line-of-sight from the top of MIT Building 24, looking over the shoulder of the Great Dome, to my 5th-floor apartment on the other side of the Charles, on Mass Ave near Beacon St. At just over a kilometer, that seemed a long enough distance to prove the point. A safely low-milliwatt helium-neon laser (the red kind) would carry our signals. A high-voltage transistor would modulate the laser’s couple-hundred volt input power. (I think we asked first, before we tore into the laser to re-engineer our transistor into the circuit.) Continue reading “Sophomoric MIT student laser work”