A lot of the "hand-waving" that is done is done for the same reason that we describe the atom using the planetary model to high school students, as the cloud model to undergraduate college students, and then using the probabilistic model to graduate physics students. There is a lot of "stuff" behind quantum calculations that need time to sink in.
My responses are all vastly simplified: 1. It's not phrased well in the show. Each qubit is both 0 and 1 simultaneously with the probability of each value being determined by the wave function by which it was programmed. 2. Same problem as #1. Basically, a problem that is solvable by a quantum computer (kind of) assigns probabilities to each bit being zero or one. When the qubits are read back, the quantum wave function (which set those probabilities) collapses so that each is read as either zero or one. 3. Qubits are not at all like transistors. Each classical bit doubles the range of possible values but doesn't double the available calculations. Each qubit actually doubles the number of available calculations. 4. Yes, very much so. Error correction is going to be critical. That's why getting more qubits in a single calculation is not just incrementally harder but polynomially harder (at least for now) as errors compound as more qubits are introduced. (this is the part I know the least about the math behind) 5. I think that was a "hopeful" statement. It's not entirely wrong but not entirely correct either. Quantum computers are great at solving problems involving a large number of probabilities (like factoring large composite numbers into their prime number components, as can be used to attack RSA). So, the shift in thinking will be not so much the programming aspect itself, but the fact that a programmer will have to describe the problem in a probabilistic way instead of a step-by-step way. Eric Rossman -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Bob Bridges Sent: Tuesday, December 5, 2023 5:41 PM To: [email protected] Subject: [EXTERNAL] Re: CBS's "60 Minutes": Quantum Computing Ok, I watched it. I learned some things, but I still don't get it: 1) Scott Pelley describes the possible states of a bit (0 or 1), and then says "Quantum encodes information on electrons ... [which] behave in a way so that they are heads AND tails and everything in between. You've gone from handling one bit of information to exponentially more data". Omitting the unfortunate misuse of "exponentially", if an electron can be in all states at once, how can a programmer, or the program, determine what data is recorded on it? I don't see how that can be true; they must be using impressive language to gloss over the details. 2) Michi Okaku likens the difference to calculating a path through a maze. A "classical" computer (his word) must check all possible turnings one at a time. But a quantum computer (he claims) "scans all possible routes simultaneously". I can't picture that, and therefore I'm doubtful; again, I suspect him of blathering about something that he really does understand but cannot describe accurately for a 60-Minutes audience. 3) We're shown a diagram of five Q-bits, and the voiceover says "Unlike transistors, each additional Q-bit doubles the computer's power". That is ~not~ "unlike transistors"; it's exactly what traditional bits do. "It's exponential", continues the voiceover, which, again, is exactly what classical bits are. "So, while 20 transistors are 20 times more powerful than one, twenty Q-bits are a ~million~ times more powerful...". Somebody should have vetted this sequence. 4) Karina Chou (sp?) of Google says their quantum computer is making an error about every 100 steps; they're aiming for one every million or so. Even at that target rate they surely need a lot of self-checking and self-correcting, no? 5) Dario Gill, when the interviewer asked whether programmers have to learn a new way of programming, responds "I think that's what's really nice, that you actually just use a regular laptop, and you write a program - very much like you would write a traditional program - but when you click on 'Go', it just happens to run on a very different kind of computer". I cannot reconcile this with the above nor with other statements being made about quantum computing. It's occurred to me that the whole quantum-computing mania might be no more than a huge hoax. I don't believe it, no. But so far I'm utterly clueless how to understand the claims about it. Regardless, thanks, Mr Sipples. Very interesting. --- Bob Bridges, [email protected], cell 336 382-7313 /* Silence promotes the presence of God, prevents many harsh and proud words, and suppresses many dangers in the way of ridiculing or harshly judging our neighbors....If you are faithful in keeping silence when it is not necessary to speak, God will preserve you from evil when it is right for you to talk. -Francois Fenelon (1651-1715) */ -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Timothy Sipples Sent: Monday, December 4, 2023 23:22 If you'd like to understand why IBM is so bullish on quantum computing - and so focused on quantum-safe cryptography - this "60 Minutes" story is well worth watching: https://www.youtube.com/watch?v=K4ssT6Dzmnw ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
