Timothy's Blog

A day in the life of a creative filmmaker

Bits and Qubits

November 4th, 2019 by

I’ve been thinking about quantum computers a bit and I think quantum computers could really change the world. The quantum computers of the future will make the supercomputers of today look like calculators. And a lot of people believe this. I think in this article I linked to it said a 300 qubit quantum computer would be equal to about 2*10^90 bits on a classical computer (that’s 2 with 90 zeros after it).

The reason this is so is because quantum computers harness the quantum nature of the atom in a way classical computers do not. Whereas classical computers calculate by simple bits, quantum computers use an entirely new thing called a qubit. Qubits aren’t really binary bits because they don’t represent a single on or off state but really a superposition of the two states that particular particle can be in and is a product of its wave function (the math behind this superposition). It’s really powerful if you think about it (and understand the physics behind it). Quantum computers basically rely on the computing power of the atom to make their calculations.

So though quantum computers will never replace classical computers because quantum computers are not good at most of what classical computers do, and though the quantum computers of today are not as powerful as we can envision they will get better and better till they surpass our expectations just like classical computers did.

IBM Q computer. Credit: Pierre Metivier

The reason quantum computers have been held back is that the quantum qubits in quantum computers are very fragile. The reason for that is that when you interact with a qubit in any way a measurement is made and the superposition of the states of the qubit collapse to just 1 or 0. Destroying the quantum information. Scientists try to get around this problem by cooling their quantum computers to a fraction of a degree above absolute zero to isolate qubits from their environments so they don’t get jostled. Unfortunately they still have a problem getting those qubits to stay that way for more than a few tens of microseconds. But there advances being made (for example using graphene as a superconducting material).

For now quantum computers remain giant super-cooled machines in researchers laboratories but some day they may become as common as your cell phone. If you remember the same thing happened with computers (think of ENIAC) and I think the same thing will probably happen with quantum computers given enough time.

I’ve linked an article I read that goes into more detail on this. Read that if your more interested in learning more. Or just google “quantum computers”. There’s a whole world out there waiting for you to explore it.

As for me, I’m thinking of studying quantum mechanics (on my own) and maybe getting a book on it. I have a recommendation from somebody I found on YouTube that will probably be good. I’ve been reading articles on Quantum Mechanics and am fascinated by the science and would like to learn more.