Quantum Computers: What Are They And Why Do They Matter?

Seeing as you’re reading this blog, I imagine it is safe to assume that you have heard of the technological phenomenon that is quantum computing. I am even going to go as far as to assume that you aren’t too sure what they are, or why you should care about them, but you have a feeling you should.

Am I right?

Good, then you’re in the right place.

Lots of the conversation around quantum computing so far has been very “futuristic” in its tone. We hear timeframes like “5 to 10 years” thrown around and it is easy to feel like this isn’t really something we should be thinking about right now. But that isn’t the case. The fact is, the quantum computers of today are already having a huge impact on our lives, and the only way to prevent this impact from being catastrophic in the very near future is to prepare ourselves right now.

So What Are Quantum Computers?

To understand how a quantum computer works, it helps to understand how a normal computer works (the kind you probably do have sat on your desk at home). An ordinary computer chip uses ‘bits’. These are basically tiny switches that can only exist in two states: on (represented by a 1) or off (represented by a 0). Everything you do on a computer is essentially made up of a code that consists of millions of ones and zeroes.

Instead of bits, quantum computers use ‘qubits’. Rather than just being on or off, these can also be in a position known as ‘superposition’ – where they’re both on and off at the same time, or neither, or somewhere between the two (complicated, right?). The best way to explain the concept of ‘superposition’ is that it is a bit like spinning a coin on its edge. It is not heads and it is not tails, it is kind of both, or neither, or somewhere in the middle!

The benefit of superposition is that it helps computers to consider lots of different possibilities at once, rather than just following a strict binary path (as an ordinary computer would). For example, If you ask an ordinary computer, or even a supercomputer, to figure its way out of a maze, it will start at the beginning and keep travelling down every available path in linear order until it reaches a dead end. Every time it reaches a dead end, it will start again at the beginning and try the next path. This does work, because (eventually) it will find the path out of the maze. BUT it can take a very long time for the computer to complete the process and solve the maze, depending on how many paths are available and where in the linear list of options the solution actually sits. When faced with the same problem, a quantum computer would choose to go down every single available path of the maze at once, finding the solution in a fraction of the time.

Cool, But Why Do They Matter?

Now you know what they are, you want to know why these crazy clever devices are important. This is an easy one. The potential of quantum computers is practically limitless. We are far from figuring out all the ways that they could help us yet, but here are just a few of them:

• Forecasting weather patterns
• Providing more accurate alerts ahead of natural disasters
• Predicting movements in the stock market
• Rapidly developing artificial intelligence technology
• Developing more effective medicines (faster and cheaper than ever before)
• Speeding up the research into (and hopefully finding a cure for) incurable diseases

Pretty impressive, right?

Unfortunately with all good must come some bad and quantum computers are no exception to this rule. The ability for these computers to review such a large volume of data simultaneously doesn’t just make them capable of solving all these amazing problems. It also makes them capable of cracking the most advanced codes, decrypting the most complex encryption techniques, and accessing even the most well-defended certificates available in the world of cyber security right now.

How?

Whilst normal computers decrypt coded data by sifting through the data using one potential code (or “key”) at a time, quantum computers are able to run multiple potential keys at the same time – speeding up the process and helping them to crack the code much faster. They’re also able to use “superposition” to find solutions that a normal computer (and even a supercomputer) would simply not see.

As you can imagine, this puts us all at risk.

But it is not all over. Thankfully, there is a group of cyber security experts in the UK right now who are working away in the background to prepare us all for the inevitable impact of quantum computers on our online safety.

The solution they have found is known as “quantum encryption” because it is a type of encryption that even quantum computers can’t decrypt (woo!). While it is obviously far more complicated than this, quantum encryption basically works by completely randomising the data it sends out (i.e. no secret code, password, or “encryption key”). Because the key is completely randomised every time a piece of data is encrypted, and there is no rhyme or reason to follow, even quantum computers aren’t able to decrypt the data. In conclusion, quantum computers are pretty damn cool. You won’t have one in your home any time soon, but they will be here soon, and they will change the world. And, now you know about them, it’s probably about time you sorted out some quantum encryption for your own online safety.