What is the origin of quantum uncertainty? | by Ethan Siegel | Starts With A Bang! | Aug, 2024

No matter how good our measurement devices get, certain quantum properties always possess an inherent uncertainty. Can we figure out why?

Perhaps the most bizarre property we’ve discovered about the Universe is that our physical reality doesn’t seem to be governed by purely deterministic laws. Instead, at a fundamental, quantum level, the laws of physics are only probabilistic: you can compute the likelihood of the possible experimental outcomes that will occur, but only by measuring the quantity in question can you truly determine what your particular system is doing at that instant in time. Furthermore, the very act of measuring/observing certain quantities leads to an increased uncertainty in certain related properties: what physicists call conjugate variables.

While many have put forth the idea that this uncertainty and indeterminism might only be apparent, and could be due to some unseen “hidden” variables that truly are deterministic, we have yet to find a mechanism that allows us to successfully predict any quantum outcomes. But could the quantum fields inherent to space be the ultimate culprit? Could it be the quantum vacuum itself that supplies whatever it is that’s necessary to cause the quantum uncertainty we experience whenever we try and make…