Quantum Computing Basics

Adam King
4 min readOct 21, 2020
Photo by Michael Dziedzic on Unsplash

TL;DR: I attempt to discuss the basics of quantum computing like superposition, entanglement, and interference AND where you can learn more about it.

Quantum computing is relatively young science that is currently being heavily researched by some of the biggest tech companies. The potential uses for quantum computing could help solve problems that have been plaguing humans for centuries. Unfortunately for someone who knows nothing about physics, it can be a BIT mind-numbing to try and research it on your own (pun-intended).

What is it?

Quantum computing refers to the applications and calculations that are performed by quantum computers. The reason they are different from regular computers is they utilize quantum ideas and concepts to perform calculations in a fraction of the time it takes normal computers. The reason they are faster has to do with the way they process and analyze information.

Normal computers convert information into binary, do some operation on the information, and then display it in a form that is readable to us. They do this by using information in the form of bits. In other words all the information input to a computer gets converted to 1’s and 0’s that can then be read by the computer and worked with. Naturally this takes a bit of time.

Quantum computers use something called qubits, which as you can probably guess, is short for a quantum bit. This is where things get a little hairy, but I’ll do my best to keep things simple. In order to talk about qubits we first have to talk about those quantum ideas and concepts.

Superposition

The first concept is superposition. This basically refers to something being in two states at once. Take the example of the bit. A bit can only be in one state, 0 or 1. However, qubits have the power to be placed in a state where they are essentially both. That state is what is known as superposition.

An example that makes a little more intuitive sense to me is flipping a coin. When you flip a coin and catch it, it is either heads or tails. However, if you flipped the coin, and it somehow just stayed in the air spinning, you could say the coin is both heads and tails at the same time. That is where the power of quantum computing comes from.

Quantum computers don’t have take in information in one state like regular computers. They are able to process and analyze the information at incredible speeds because they are essentially in two states at once. However, this speed comes with it’s own dilemmas. In order to talk about them we have to know about entanglement and noise

Entanglement

Entanglement is difficult to talk about without using some of the terminology. So to make things simple I will use the word “thing” to take the place of some fancy quantum physics word.

Entanglement is another concept in quantum physics that has to do with the relationship between two things. When two things become entangled they behave in a special way that very little is known about. The way I think about it is that once entanglement occurs, a connection is formed between the two things.

Entanglement is special because observing the two entangled things can give insight to the information that is being received from them. Basically, if you tried to look at the things individually, you would think they were giving off random signals. But when you look at them as a system you can more easily understand the information.

Interference

What makes quantum computers so incredibly fast is also what makes the information obtained from them prone to error. When we have a qubit in a superposition state we know that information can be processed very quickly. The tricky part, is that when we try to get information from that qubit, or what is known as “observe” it, we ruin the superposition.

This is where the term interference comes in. A lot of the information we get from these qubits can be flawed due to the fact that it is random. This is what generates interference or more commonly referred to as noise. One of the biggest challenges of quantum computing today is figuring out how to reduce the amount of noise that is produced by quantum systems.

What it all means

Hopefully all of that made some sort of sense. Now that my brain is sufficiently numb I’ll try and bring all of that quantum stuff together. The main gist is quantum computers work by using qubits to process massive amounts of information really quickly. They do this by magic a.k.a complicated quantum stuff.

Unfortunately the qubits don’t produce 100% accurate information due to the idea of noise. This problem is the main issue of quantum computing today and there are tons of scientists working on the problem everyday.

Why it’s important

You may be thinking, why does this even matter. Well the applications of quantum computer have potentially far reaching effects. If you’re a software engineer like me then quantum computing could have huge impacts on running machine learning models or breaking encryptions. For other science fields, that ability to process information quickly can allow for possible models to be made that mimic natural processes, which would be HUGE.

I want more!

If you’re thinking my brain isn’t nearly numb enough, then you can head on over to IBM’s website where they have a ton of great resources and classes to learn more about it. If you’re more of a hands on person, they actually have quantum computers you can access through the cloud and integrate with some of your programs.

I hope this blog post has helped you gain some understanding of quantum computing and what it entails. Personally this a technology I am very excited for and will continue to try and learn more about. If you enjoy this stuff like I do send me a message on LinkedIn and we can numb our brains together.

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Adam King

Software engineer sharing stories of my experiences in a coding bootcamp and beyond.