---If you ever get a sprained wrist, you'll be locked out of your computer. Hopefully, there would be alternate authentication methods built in. And what happens if you don't log into your computer for an extended period of time? After I learned to type (taking lots of notes does that to you), my typing ability and methods (and patterns/rhythms) had completely changed. That was in the course of a month. At the end of that time, I would have been locked out of my computer.

As far as I can tell, we need to focus on dealing with the presence of drones and "killer robots," not how to prevent them. Like it or not, 'progress marches on'.

BUT, as the researchers go on to say, it's the 'valley of inaccessibility' only because “between, say, 5 or 7 THz and 30 THz, we don't have any really good sources to make our own controlled frequency.” What we should actually be worried about is whether the phenomenon actually exists. (Also according to the article.)

What I see happening is that when/if this is implemented, some hacker figures out how to activate all the bracelets in the airport, as a protest against their use -- which the government classifies as yet another terrorist act.