Scientists at Microsoft and their partners around the world have spent the last decade
exploring the exciting and utterly bizarre place where computer science and quantum physics
collide. So where's that, exactly?
Think about quantum computing like a subway map with two train lines--the Quantum Physics
Local and the Computer Science Express--coming from different directions to meet at a central
hub: Station Q. On the map, the two lines meet and continue
forward together, though no one knows exactly where they're headed.
Thanks to brilliant minds from Newton to Einstein, we have a pretty solid understanding of matter,
motion, time, space, and how the universe generally functions. But over the last hundred
or so years, scientists looking closely at life on an atomic and sub-atomic level started
noticing some inconsistencies with traditional physics. Questions and theories started piling
up about how and why particles seem to behave predictably on a large scale (like plants
and birds and rocks and things), but on a nanoscale it's, well, particles gone wild.
It turns out that behaviors that seem impossible to imagine on a human scale are downright
pedestrian at a molecular level. Down there, particles - little balls of solid matter - act
like waves. Particles teleport from one place to another, and can also become "entangled,"
making it impossible to separate them. In a quantum state, particles can even achieve
something we call superposition, where they exist in multiple states simultaneously.
You've ridden this line many times before. You know that the laptop on your desk, the
smartphone in your hand, and the tablet in your bag all work with information in the
form of bits. Bits, which can be either a 1 or a 0, are arranged in long, artful strings
to get computers to do all sorts of things, like sequence DNA or fling angry little birds
at pig-built fortresses. But classical computers have limits to their
problem-solving prowess. There are some problems so difficult that even if all the computers
in the world worked on the problem in tandem it would still take them a very long time
to solve it. So here's where things REALLY get interesting
and where quantum computing could come in handy. Quantum computers run on quantum bits,
or qubits. Because of the mind-bending properties of a quantum state, like superposition, a
qubit can be a 1 or a 0 - or it can exist as a 1 and a 0 at the same time. If one qubit,
as a 1 and a 0, can do two calculations, then two qubits can do four, four can do eight,
and the computing power has the potential to grow exponentially.
With long strings of qubits performing computations, problems that would take today's computers
eons to solve could be tackled in the time it takes to grab a cup of coffee.
This could have wildest imagination-type applications in fields such as machine learning and medicine,
chemistry and cryptography, materials science and engineering. And could allow humans to
understand and control the very building blocks of the universe.