Oddly, Too Much Weirdness Slows a Quantum Computer Down
Adrian Y. Cho · Science · 2009
Physicists dream of creating quantum computers that can swiftly solve problems that overwhelm the best conventional computers. Schemes for making the devices rely on a mysterious quantum connection called "entanglement," through which a measurement made on one particle can instantly affect the state of others. But too much entanglement is bad for a quantum computer and makes it run only marginally faster than a conventional one, a new analysis shows. "A lot of people, including myself, were surprised by this," says Richard Jozsa, a mathematical physicist at the University of Bristol in the United Kingdom "It's a thought-provoking result."