The Turf Tavern Tribulation

Why you can't clone an unknown qubit

Mission 2: The Art of Quantum Messages. Part of the Quantum Courier Service, a free course from the Oxford University Quantum Information Society.

Pull up a bench at the Turf Tavern, recruit, and prepare to blow a hefty portion of the Echo Network's black budget on a game you are mathematically guaranteed to lose. A rogue physicist has placed an unknown qubit on the felt, and we are going to step into the enemy's expensive loafers to prove exactly why they can't clone our secure data. Your orders are delightfully reckless: select either the [+] Computational or [x] Diagonal laser to zap the qubit and read the collapsed result, then wager $100,000 of the network's funds on what the original state was before you destroyed it. Pay close attention to the math, old chap; if you intercept a qubit with the wrong basis filter, the universe will panic, randomize the data, and leave you paying a fortune just to flip a virtual coin. Try not to make a complete dog's dinner of it. Chop chop!