What is the quantum object called “Alice’s Loop” that scientists created?

The literary works of Lewis Carroll and their complex intrigues Quantum physics They rarely cross paths – but when they do, it’s as soul-crushing as it gets.

Last month, scientists from Aalto University in Finland and Amherst College in Massachusetts created a strange quantum object known as the Alice Ring, The Verge reported. Popular Mechanics.

An homage to the eponymous character Carroll in Alice’s Adventures in Wonderland, the name is appropriate.

This separate monopole – a particle with only one magnetic pole – opens a “vortex ring” that reverses the direction of the magnetism Magnetic Charge any other monopoly that passes through their centre, creating “antitrust”. The results of the study were published on Tuesday (10/17) in the magazine Nature Communications.

“Monopoles and vortexes are fundamental topological excitations that occur in physical systems that span enormous scales and energy scales, from the vastness of the early universe to tiny laboratory droplets of nematic fluids.” Crystals And ultra-cold gases,” the study says.

“Although the topologies of vortices and monopoles are different from each other, under certain conditions, a monopole can spontaneously and continuously deform into a vortex ring with the curious property that monopolies passing through it turn into anti-monopolies.”

There are two phenomena called “monopoles” roaming the world of physics. There are magnetic monopoles, first developed by the English physicist Paul Dirac in the 1930s, which still constitute hypothetical elementary elements. particledespite a century of research (including Major projects at CERN).

Then there are topological monopoles, which arise from quantum fields that create one-sided magnetism reminiscent of monopoles. Mottonen, in collaboration with colleague David Hall, created topological monoliths by placing 250,000 rubidium atoms in a vacuum chamber, bombarding them with a laser to slow their motion, and lowering temperatures to approximately Absolute zero To form what is known as a Bose-Einstein condensate. Once they reach this extremely cold state, the atoms act as a quantum object

Because of the quantum property known as spin (where the spin of a subatomic particle interacts with magnetic fields to produce torque), Mottonen and Hall used Simulation Computer and mathematical models to apply the correct amount Magnetic force to produce defects, known as topological monopoles.

Alice’s Adventures in Wonderland is long enough to fill the pages of two entire novels, but these quantum defects are incredibly short-lived, lasting only a few milliseconds. Mottonen compares topological monads to an egg swinging on the top of a hill, a small disturbance, e.g the sound, can cause the monopole to begin to decompose into an Alice ring. But unlike monopoles, Alice rings have the ability to last for 80 milliseconds, about 20 times longer than the monopole itself.

“From a distance, Alice’s ring looks like a monopole, but the world takes on a different shape when looking through the center of the ring,” Hall said. In a press release.

“From this perspective everything seems to be reversed, as if the ring were a portal to a world Antimatter Instead of the material,” Mottonen added. “This was the first time our collaboration was able to create Alice in the Wild episodes, which was a tremendous achievement.”

The next step for Motonen, Hall and the rest of the team is to send experimental monopoles through the ring to observe this reflection directly, while also exploring its applications in Cosmology And high energy physics.