Quantum Randomness

We demonstrate that quantization entails randomness in microscopic processes. Unlike classical random processes that arise from incomplete human knowledge, quantum randomness arises from nature and is perfect. Radioactive decay is a prominent example. Heisenberg’s uncertainty principle quantifies quantum randomness by putting limits on the degree of uncertainty in particular pairs of observable quantities. The diffraction of an electron passing through a 1-slit experiment offers an instructive example of this principle. Quantum uncertainties make it difficult to assign a definite “size” to microscopic objects. Randomness is inherent in the wave nature of all quanta. As we will see in more detail in Chap. 9 , quantum randomness is essential to meet the relativistic requirement that information cannot be transferred superluminally.