"Quantum credit cards" sound so much like snake oil (in the computer security context) it hurts. The underlying paper: https://www.osapublishing.org/optica/ful

"Quantum credit cards" sound so much like snake oil (in the computer security context) it hurts. The underlying paper: https://www.osapublishing.org/optica/fulltext.cfm?uri=optica-1-6-421 https://www.osapublishing.org/optica/fulltext.cfm?uri=optica... Why? Because no sane attacker is interested in placing his probe between the laser and the card, but in the plain traditional electronics that controls the laser. If I were an attacker I couldn't care less that you send "a quantum state" with the laser in the card reader. It's just the plain classical bits on the level I'd be interested in. To protect from that, you'd need the full "quantum internet" to every credit card reader! Which is exactly what djb claims is wrong with the "Quantum Manifesto:" making grandiose security claims that can't stand to the scrutiny of "classical" security researchers, as soon as the whole implementation is considered: "an embarrassingly oversimplified model of the attacker that allows the attacker to inspect photons being sent between quantum-cryptography devices but that does not allow the attacker to interact with the devices in any other way."