Have you ever heard the term “Quantum Computer” and wondered what it meant?   A Quantum computer has the potential to revolutionise the way we think about computers and how they work.

It’s going to be tricky to explain, so let me start by explaining how traditional computers work.

All computers are based on what’s called a binary system.  This is the principal that everything is either on or off.  On is represented by “1” and off by “0”.   It’s hard to believe, but everything with a processor in it – from cell phones to super computers, simply work by turning transistors on and off.

Programs are written to process series of 1s and 0s which represent data.   These 1s and 0s are what get written to a hard drive when you save a document or take a photo.

Technology has advanced so far that the old tubes and transistors are now only slightly larger than an atom!    It’s astonishing how intricate modern-day processors are now and just how powerful they’ve become in such a short space of time.

However, we’re reaching a plateau where it’s becoming increasingly difficult to shrink transistors any further.   Instead, a radical approach is being investigated, which no longer relies on the two states of on and off to process data.

Here’s where Quantum computers step in.   Going further than atoms, Quantum physics describes the state of the sub-atomic particles that make up atoms.   And these sub-atomic particles are where things get really weird.  Where binary can only be on or off, sub atomic particles can be both at the same time.   Yes, you read that right – these particles are like nothing else and can’t be explained by the normal laws of physics.

Think of a sphere, where a computer bit can be at either pole of the sphere – on or off.   A Qubit (or a Quantum Bit) can be at any point on the surface of the sphere.   This means that Qubits can represent huge amounts of data very simply.

As an example, imagine a traditional computer trying to solve a maze.  It would have to go down every path, one after another, until it discovered the way out.   Alternatively, a quantum computer could travel down every path simultaneously.

This has ground-breaking implications for processing complex problems and large data sets.   Problems which are too complex for modern day computers to solve are known as “intractable” problems.   It’s these Intractable problems that could someday become solvable.

Sounds amazing doesn’t it!  The only problem is building a Quantum Computer – it’s not easy!

Companies like Microsoft, Google and IBM are all battling to develop useable quantum computers.

In November 2017 IBM announced that they’d reached a milestone in developing a 50 Qubit computer.   The only drawback was that it was only stable for 90 microseconds!

Google on the other hand have been offering scientists access to a 5 Qubit computer since 2016 and in 2017 announced they can now handle 20 Qubits.

Little known Californian startup Rigetti is instead focusing on the stability of Qubits, rather than quantity and could be the first company to develop a stable quantum computer that can be successfully used.

A Canadian (Vancouver) company called D-Wave have controversially announced that they’re manufacturing 2000 Qubit computers, however scientists are sceptical that they’re true Quantum Computers.

If all this sounds mind boggling, it really is!   What it does show is that a few years from now, computers may be incredibly powerful and able to solve problems that we currently consider impossible.

It’s an exciting time and it’ll be interesting to watch how the world of Quantum Computers develops over the next few years!