Crimson, eleven, delight, petrichor.  That’s what Idris told Rory to have Amy think of in order to open the psychic lock that would lead them to safety.  It was a clever bit of Doctor Who SciFi-ness, but who would ever think it could ever be something you might find in the real world?  Well, if researchers at the Berkely School of Information have anything to say about it we could all be using “pass-thoughts” in the near future.

“…the experiment’s subjects were asked to imagine a series of select actions, such as singing a particular song or imaging a set of objects of a particular color. These pass-thoughts enabled the participants to repeatedly identify themselves to the computer.”
That is exactly the method used in Doctor Who!
Although they don’t go into limits of the security of such mental passwords I think its safe to assume they’d be pretty unbreakable.  I’ve no doubt some nefarious individual would work out a way to crack mental passwords, but it just seems to me that the combinations are literally infinite.  I mean, if even one element of the pass-thought is something you completely made up, how could that ever be hacked?
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