A century of quantum physics
A Nature special

A century of quantum physics
13 March 2023

Although the basic idea of quantum physics dates back to the earliest years of the twentieth century, it wasn’t until 1925, on the German island of Heligoland, that Werner Heisenberg had the inspiration that marked the true dawn of quantum theory. With stunning speed over a few short years, a whole new paradigm of material reality emerged to overturn all of the classical physics that preceded it.
This quantum world is one that is fundamentally at odds with our intuitions: particles and waves shape-shift into one another; nothing can ever be completely certain; and the act of observing seems to play a central part in determining what is observed. The questions this world raises are immense, and its relationship with the other pillar of modern physics — Albert Einstein’s general theory of relativity — is uneasy. Yet the promise of quantum computers and other technologies built on the back of it are enough to convince that, a century on, quantum theory is here to stay.
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