What is Quantum Computing?
I enjoy non-fiction, namely Amit Katwala’s ‘Quantum Computing: What It Is And How It Could Change The World’ and I’m excited to share my discoveries in this episode of Madi Investigates…
I have always had an interest in quantum computing. “Why?” I most certainly do not hear you asking. Well, it seems otherworldly. Some crazy philosophical concept that shouldn’t exist – but somehow does. Basically, it makes me feel smart. I am hoping you will enjoy our session today and be able to regurgitate a thing or two for truly impressing your friends in the pub.
Um, quantum?
Normal computer systems are made up of little electrical charges that are either on or off (all that matrix-esc 1100101). Quantum computing uses quantum-bits – most people are too lazy to use that many letters though, so we call them qbits. A qbit can be made of anything: electrons, photons, etc. They can be on, they can be off, they can be neither, they can be both; clearly, they can be confusing. This is all down to an incredible phenomenon where, in special circumstances, qbits will become essentially both on and off at the same time, this is called a state of superposition. I know right, sounds like something from Schrödinger.
What’s in it for me?
Two normal bits can either be 00, 01, 10 or 11 but a single qbit in superposition can be all four at once. Hence, while a regular computer can only take one path at a time to solve a problem, quantum computers will theoretically be able to look at every path at once, as if four computers were running at once. Many computer science fangirls have already created the algorithms to be run specifically on quantum computers, we just need something to run them on.
So where are they?
Quantum processors have already been created in many companies, famously there is IBM’s claim at a 127 qbit processor, with even larger ones in other less-known companies. So of course I had to wonder, why do my friends make confused faces at me when I talk about them?
Well, it turns out the special circumstances needed for a superposed qbit make them extremely difficult to work with. Trying to measure something that doesn’t want to be seen is already a challenge; they don’t like summer and in fact prefer essentially absolute zero; any interference from anywhere will push it out of superposition… Qbits: the fussy toddlers that are so difficult to control, scientists were impressed when some stopped crying for two milliseconds.
The sum-up supreme
Most big companies are aiming for ‘quantum supremacy’, a phrase which here means, when a quantum controlled computer can perform things a regular computer can only dream of. No, not finally understanding how to properly use the mobile app (that may be beyond anybody), more like digitally simulating the workings of a hydrogen atom. They will make computing much more powerful, and we are already able to use them in new and exciting ways.
I hope you have enjoyed our adventure together today and even better, learnt something a little bit new to add to your portfolio of knowledge.
Until next time,
Madi
