The Tiny Donut That Proved We Still Don't Understand Magnetism

Potentials influence reality

Potentials can influence reality even when fields are zero. The Aharonov-Bohm effect shows electrons' wave functions shift due to magnetic potentials, not just fields, proving potentials have physical significance.

• 🧲 The Aharonov-Bohm effect was first theorized in the 1950s, challenging the idea that only fields have physical reality.
• 🔬 Early experiments struggled to isolate the potential's effect from stray magnetic fields.
• 🍩 Akira Tonomura's 1986 experiment using a donut-shaped magnet provided strong evidence by confining the magnetic field.
• ⚛️ A gravitational Aharonov-Bohm effect was experimentally tested in 2022, suggesting potentials influence reality across forces.

A finger holds a tiny ring-shaped object, with a magnified inset showing a close-up of the object.