The Uncertainty Principle

Werner Heisenberg showed something fundamental: you cannot know a particle's exact position AND exact momentum at the same time. Measure one more precisely, and the other gets fuzzier.

This isn't a technology problem — no better instrument will fix it. Uncertainty is built into the fabric of reality.

For everyday objects, the effect is far too tiny to notice — a baseball's position is uncertain by less than a trillionth of an atom. But for electrons, the uncertainty is everything.