What is quantum computing?

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Quantum computers often grab the science headlines. Offering unprecedented computing power, they are set to revolutionise the world of computing as we know it. But what exactly is quantum computing? What will quantum computers be able to do, and when can we expect to have fully functional ones? The articles below provide some answers. You can read them in sequence, but they also work stand-alone.

These articles are part of our Information about information project. We also bring you two related articles from FQXi who are our partners on this project. Happy reading!

How does quantum computing work? — This article introduces you to the basic idea behind quantum computing, how it makes use of strange quantum phenomena like superposition and entanglement, and why these are supposed to make it so powerful.

Quantum computing: Some (not so) gruesome details — We delve a little deeper into a quantum algorithm, picking apart what makes it work. Nature has been kind in the maths that's involved quite basic, so even novices can follow the ideas.

What can quantum computers do? — Many sensational claims have been made about quantum computers. That they'll break all internet security in the blink of an eye, for example, and that they'll be able to solve some of the hardest problems you can think of. We investigate whether these claims are true and what we really can expect from quantum computers.

Do quantum computers exist? — Do fully-functional quantum computers already exist? If not, then why not? And when can we expect to have them?

The following articles first appeared on the FQXi website.

Quantum computers get real — Some recent developments in the attempt to build useful quantum computers.


Quantum in context — An untapped resource could provide the magic needed for quantum computation—and perhaps even open the door to time travel.