Quantum Test Pricks Heisenberg Uncertainty Principle
The Heisenberg uncertainty principle is in part an embodiment of the idea that in the quantum world, the mere act of observing an event changes it. But the idea had never been put to the test, and a team writing in Physical Review Letters says “weak measurements” prove the rule was never quite right. That could play havoc with “uncrackable codes” of quantum cryptography.
Quantum mechanics has since its very inception raised a great many philosophical and metaphysical debates about the nature of nature itself. Heisenberg’s uncertainty principle started as an assertion that when trying to measure one aspect of a particle precisely, say its position, experimenters would necessarily “blur out” the precision in its speed. That raised the spectre of a physical world whose nature was, beyond some fundamental level, unknowable. This problem with the act of measuring is not confined to the quantum world, explained senior author of the new study.