Quantum Computers

Written by Yuvraj Dhillon

In a world of pace-driven technology, effortless computing and nanosecond calculations, knowing and exploring the limits of human technology is important.

One of the best revelations in technology is that of quantum computing. First, let us see what ‘quantum’ even means. Yeah, we all know that you've heard it and seen it in Avengers Endgame (2019) when the team travels back in time. ‘Quantum’ itself means the smallest possibility of anything, the smallest that makes up the stuff we see in real life. So Quantum Computing, would, in principle, mean the kind of computing that makes use of the smallest “stuff” that make up the universe, to do calculations.

Okay, so know you know what quantum computing is. But how does it work? It all works on the science of Quantum Mechanics( Okay, I know I'm just putting quantum before everything), which is the branch of physics concerned with the study of the smallest things making up the universe- particles. Quantum Computing uses the principles of Quantum Mechanics like Superposition and Entanglement. We will get into that in a moment. But in the end, they have potentially unlimited applications. With the use of Quantum Computers, computers can take multiple paths instead of one at the same time.

Imagine a maze. You're stuck in one spot and you have no idea which path to take. There are many possibilities, only one of which can correspond to you getting out of the maze.

With a conventional computer, like your normal laptop, phone, etc., it would take a tremendous amount of time to calculate which path to take, because a conventional computer uses data- bits- which takes a lot of time, as it would explore the potential outcome of every possible path, one at a time. In comparison, if you had a quantum computer, it would take less than nanoseconds, because the computer would take all different paths at the same time, and you would get the result even faster.

Mind-blowing right?! But how is this possible? Well, essentially, it's all because of Qubits- quantum bits of information. They are just like bits( 1s and 0s), the only difference is they are in a state of superposition, which means at any given time, a given qubit can either be both a 1 and a 0. Yep, you heard it right, they both exist at the same time as the same thing. But when we measure them at any one time, they collapse and become EITHER a 1 or a 0. So this means that they can store information in powers of 2. For example, if there are two qubits they can store 2^2 bits of information, 5 bits can store 2^5 bits of information and so on.

This means quantum computers can store exponential amounts of data and are very much faster in processing than a classical computer. Thus quantum computers have a plethora of applications, from making database searching faster, to making use of simulations to picture molecules, viruses and other small things. There are so many potential applications that we can only know if we start exploring quantum computers more.

There is one huge misconception when it comes to quantum computers though. We may use this to revolutionize database searching and transfer of information, but when it comes to calculating normal stuff a classical computer is better for the job. If you need to watch Youtube or browse Facebook, a classical computer is enough for that. But if you need to find out how many atoms there are in the universe, or how many possible futures you can have, then a Quantum Computer wins the round.

IBM has already made a 50-bit quantum computer, and it looks something like this. From afar, it looks like a steampunk chandelier.

Google and Microsoft are both working on Quantum Computers as well. There's still a lot of time though, it may take another 10 years to make this technology possible, so go on using your normal computers for the time being :)