Hypnotic Water Vortex Experiment Visualizes Elusive Aharonov-Bohm Quantum Effect Using Counter-Rotating Standing Wave Patterns

OIST physicists use a water vortex to simulate the Aharonov-Bohm effect, revealing rotating wave patterns that explain invisible quantum behaviors.

By: AXL Media

Published: Apr 20, 2026, 8:55 AM EDT

Source: Information for this report was sourced from EurekAlert!

Classical Analogues for Quantum Phenomena

In the complex realm of quantum mechanics, particles frequently react to forces they never physically touch, a phenomenon exemplified by the Aharonov-Bohm (AB) effect. While electrons are influenced by magnetic fields confined within solenoids they do not enter, these phase shifts have historically been nearly impossible to observe directly. However, a study published today, April 20, 2026, in Communications Physics, reveals that researchers from the Okinawa Institute of Science and Technology (OIST) have successfully used water waves to make these invisible topological effects visible to the naked eye.

Evolution of the Berry Fluid Model

The research builds upon the work of theoretical physicist Michael Berry, who in 1980 first demonstrated that a draining vortex in a water tank could serve as a classical stand-in for a quantum solenoid. In Berry's original model, traveling waves passing a vortex developed a distinctive "pitchfork" distortion, signifying a phase shift. The OIST team, in collaboration with the University of Oslo and Universidad Adolfo Ibáñez, decided to push this analogy further by exploring what happens when waves are introduced from two directions simultaneously, challenging long-standing intuitions about wave interference.

The Discovery of Counter Rotating Nodal Lines

When the researchers generated waves from opposite sides of a custom-built tank, the presence of a central vortex created a pattern that neither canceled out nor simply doubled the existing distortions. Instead, the interference resulted in "nodal lines," which are rotating segments of momentarily still water that radiate outward from the center. Co-first author Aditya Singh noted that these lines exhibit a peculiar behavior by always rotating in the opposite direction of the vortex’s flow. As the intensity of the vortex increases, the number of these nodal lines grows, creating a hypnotic visual representation of system-wide topological shifts.