The Scientific Value of Ignorance

livemint.com:

In George Orwell’s novel “1984," “Ignorance is Strength" is a shocking slogan that epitomizes a corrupt and sinister regime. But in the more nuanced form “Ignorance Can Be Strength," it is an apt slogan for some cutting-edge science. Used wisely, ignorance can be a superpower that makes our senses (and measuring devices) more acute and our minds (and computers) more capacious.

This seeming paradox is rooted in the nature of quantum reality, which tells us that there is a fundamental limitation concerning how definite our knowledge we can be about the position and momentum of an object. We can predict probabilities for where a particle will be found and how fast it will be seen to move, if we measure those things. But according to quantum theory, the product of the fuzziness in predicted position and the fuzziness in predicted momentum cannot be reduced below a definite limit.

That is Heisenberg’s uncertainty principle. Now suppose that we’d like to measure the position of an object very precisely, so that we can detect the tiny distortions of space caused by gravitational waves. To minimize the fuzziness in its position, while remaining in Heisenberg’s good graces, we need to crank up the fuzziness in its momentum.

The main difficulty in making good quantum computers is keeping Nature ignorant about what they’re doing. A classical computer runs through a sequence of definite “positions," each consisting of a series of 0s and 1s that represent the states of its transistors. A quantum computer, like a quantum particle, allows all these “positions" to coexist.