What is Quantum Computing?
Whilst modern day computers are truly remarkable, there are still some problems that are so complex, that they become impossible to process using traditional technology approaches. Quantum computing can help us change this in our favour, opening new opportunities to solve some of the worlds most pressing problems in areas of national security, climate change, financial and cyber security and of course learning and education. Although quantum computing is relatively new in the public eye, the benefits of and principles involved have been discussed in scientific circles for over 30 years.
Quantum computing takes advantage of curious and often baffling quantum effects that become visible at the sub atomic level of the physical world around us. Unlike a traditional computer, which uses information stored in bits as 0's and 1's; a quantum system uses qubits.
A qubit can be thought of a little like a closed box, inside which there is a light that is constantly changing colour. When the box is opened the colour freezes and you see one colour, but when it is closed, the light (although we know it is changing) could be any one of the many possible colours. The chances of seeing a red light or a blue light become a matter of probability governed by multiple factors.
We call this a superposition state – in which we can say that the light is a superposition of all colours at the same time. This is the subject of the famous 'Schrodingers's cat'. Scientist Erwin Schrodinger stated that a cat in a closed box is both dead 'and' alive until you open the box to find out. We sometimes call it the uncertainty principle.
When more than one qubit is reliably connected to another, the qubits are said to be entangled. This makes the qubits a powerful tool in solving extremely difficult mathematical problems that would be normally considered exponential or intractable in nature.
Intractable simply means difficult, or that the more variables involved the possible answers increase not by one or two but perhaps by millions and billions. Problems like recognising faces in digital images, planning routes and modelling the galaxies all have inherent difficulties that quantum computing will help to solve.