Physicists connect time crystals twice in a seemingly impossible experiment

Physicists have created a system of two interconnected time crystals, two strange quantum systems stuck in an endless loop to which the ordinary laws of thermodynamics do not apply. By linking time crystals together, physicists hope to use the technology to build a new type of quantum computer.

“It is a rare privilege to be exploring an entirely new phase of matter,” Samuli Autti, lead scientist on the project from Lancaster University in the UK, told Live Science in an email.

From crystal to time crystal

We encounter natural crystals all the time in everyday life, from ice in a cocktail to diamonds in jewelry. While crystals are beautiful, to the physicist they represent a breakdown of the natural symmetries in nature.

The laws of physics are symmetrical across space. This means that the basic equations for gravity or Electromagnetic Or quantum mechanics equally applied to the entirety of the volume Universe. They also work in any direction. So, a lab experiment rotated 90 degrees should produce the same results (everything else being equal, of course).

But in crystal, this wonderful symmetry is broken. The crystal particles arrange themselves in the preferred direction, creating a repetitive spatial structure. In the language of physicists, a crystal is a great example of “spontaneous symmetry breaking” – the basic laws of physics remain the same, but the arrangement of the particles is not.

In 2012, physicist Frank Wilczek of the Massachusetts Institute of Technology noted that the laws of physics also have time symmetry. This means any experience is repeated at a later time time It should lead to the same result. Wilczyk made an analogy with ordinary crystals, but in the time dimension, this spontaneous symmetry was called the time crystal breakthrough. After a few years, physicists were finally able to build one.

quantum secrets

“A time crystal keeps in motion and periodically repeats itself in time in the absence of external encouragement,” Otti said. This is possible because the time crystal is in its lowest energy state. The basic rules of quantum mechanics prevent motion from becoming completely stationary, and so a time crystal remains “stuck” in its never-ending cycle.

“This means that they are perpetually moving machines, and therefore impossible,” Otti said.

The Laws of Thermodynamics It suggests that systems in equilibrium tend toward more entropy, or turbulence—a cup of coffee sitting outside will always cool, the pendulum will eventually stop swinging, and a ball rolling on the ground will eventually rest. But time crystal challenges that, or simply ignores it, because the rules of thermodynamics do not seem to apply to it. Instead, time crystals are governed by quantum mechanics, the rules that govern the zoo of subatomic particles.

“In quantum physics, a perpetual motion machine is fine as long as we close our eyes, and it should only start to slow down if we observe motion,” Otti said, referring to the fact that the strange quantum mechanical states required for time cannot continue to function as crystals once interact with their environment ( For example, if we notice them).

This means that physicists cannot directly observe time crystals. The moment they try to watch one, the quantum rules that allow them to exist disintegrate, and the crystal of time stops. This concept extends well beyond observation: any strong enough interaction with the external environment that breaks the quantum state of a time crystal will make it cease to be a time crystal.

This is where the Autti team came in, trying to find a way to interact with a quantum time crystal through classical observations. At the smallest scale, quantum physics prevails. But insects, cats, planets, and black holes are best described by the deterministic rules of classical mechanics.

“The continuum from quantum physics to classical physics is still poorly understood. How one becomes the other is one of the outstanding mysteries of modern physics. Time crystals span part of the interface between the two worlds. Perhaps we can learn how to remove the interface by studying crystals,” said Otti. time in detail.

Magical Majoons

In the new study, Otti and his team used “Magnons” to build their time crystal. Magnons are “quasiparticles” that appear in the collective state of a group of atoms. In this case, the team of physicists took helium-3 — a helium atom that contains two protons but only one neutron — and cooled it to a ten thousandth of a degree above absolute zero. At that temperature, helium-3 turns into a Bose-Einstein condensate, in which all atoms share a common quantum state and work in concert with each other.

In this capacitor, all the coils of electrons in helium-3 are bound together and work together, producing waves of magnetic energy, magnetons. These waves rushed back and forth forever, making it a time crystal.

The Ooty team took two sets of magnons, each acting as its own time crystal, and brought them close enough to affect each other. The combined system of magnons acted as a one-time crystal with two different states.

Otti’s team hopes that their experiments can clarify the relationship between quantum and classical physics. Their goal is to build time crystals that interact with their environments without disintegrating quantum states, allowing the time crystal to continue to function while it is being used for something else. It doesn’t mean free energy – the motion associated with a time crystal has no kinetic energy in the usual sense, but it can be used in quantum computing.

The presence of two cases is important, because this is the basis of the calculation. In classical computer systems, the basic unit of information is a bit, which can take a state of 0 or 1, while in quantum computing, each “qubit” can be in more than one place at the same time, allowing for more computing power.

This could mean that time crystals can be used as a building block for quantum devices that also operate outside the laboratory. In a project like this, the two-tier system that we have now built will serve as a building block,” said Otti.

This work is currently very far from a working quantum computer, but it opens up interesting areas of research. If scientists can manipulate the two-time crystal system without destroying its quantum states, they can build larger systems of time crystals that act as real computational devices.

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