Anyone who's researched the infamous double-slit experiment knows exactly how strange light can behave when it "chooses" which property to display. Following this weird characteristic, a team of researchers have basically duplicated the effects with flowing liquid instead of light, which also demonstrated an interference pattern when split.
An Impossible Experiment?
In the double-slit experiment, light displays properties of both a particle and a wave depending on how the beams are split through and recombine. Normally when a beam is sent through the slots, they recombine into a solid points of light on the other side. However, when the beams are split up before being forced through each slit, the light is diffused throughout the wall in a wave pattern.
Somehow the beams interact with themselves when traveling and smaller slits result in a larger interference pattern. Even though both slots should determine to some degree how the light collects on the other-side, the particles refuse to act in accordance and continues its display in a wave.
Liquid Flows Bright
Researchers have now demonstrated this strange effect utilizing a "superfluid" dubbed ultra-cold helium-3. Duplicating the mechanics of a superconducting quantum interference device or SQUID, the machine uses electrical currents to detect any magnetic field changes. The setup includes a super-conducting ring which electrons flow through and recombine at the end.
Constricted by a Josephson junction, the ring utilizes a tiny sandbar that also affects the wave structure of the electron current. As the magnetic field passes through the ring, it affects both halves in differing ways which de-synchronizes the recombination efforts of the currents. A small increase in the magnetic field causes both waves to line up peak-to-trough (interference pattern) and a large increase causes peak-to-peak effects for maximum intensity.
Scientists have been trying to figure out what causes this phenomenon ever since Thomas Young first performed this experiment in the early 1800s. Although the results can be duplicated with objects larger than protons and electrons, the difficulty of controlling them also increases. In order to get a better idea on what was happening, researchers have also attempted to fire the electrons one-by-one to see if the effects could be different. Nothing would change however as the electrons continued "interfering" with themselves and creating a wave pattern regardless of methodology.
Not So Smart Anymore
As curiosity was pushed further, researchers attempted to place an electron detector to determine which slit each electron traveled through to figure out how it was interacting with each slit. What they found however is the particles would revert back to their normal particle state with diffusion non-existent.
The reason why this experiment has confused so many is because the act of "watching" or detecting which slit the electron traveled through also changed the results of the experiment. The very act of measuring should not affect the way light behaves...so this experiment continues to confuse even the most intelligent theorists to date.
Written By: Nick Long
Source: "Flowing liquid revealed as quantum wave"