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Scientists create strange matter in which time has ‘two dimensions’

Scientists have created a new phase of matter, in which time has two dimensions.

The creation of an “extra” dimension in time could change the way we think about matter as well as helping build quantum computers that could themselves change the world, according to the researchers who found it.

And the perplexing quality was discovered in an almost equally astonishing way: by shining lasers, flashing in a pattern of pulses inspired by the Fibonacci sequence, at atoms inside of a quantum computer.

When researchers did that, they found the strange phase of matter. It has two dimensions, but still flows in just one direction, according to the scientists.

That brings years of theoretical research into experimental reality, the scientists say.

The research is reported in a new paper, ‘Dynamical topological phase realized in a trapped-ion quantum simulator’, published in the journal Nature.

The strange phase of matter could be of key use to the scientists who are trying to build dependable quantum computers. Such technology could change the world by allowing for calculations that would have been previously practically impossible, but it has proven difficult to ensure they are dependable and robust enough to actually be used.

In the new phase of matter, information that is stored is much better protected against errors than in other systems that are currently used in quantum computers. That means that information can be kept around for a lot longer, which in turn will make quantum computing much more likely.

Quantum computers are powered by qubits, or quantum bits, which are like the bits in a computer. They are made of atomic ions and can be off, on, or a combination of the two.

But interacting with qubits can unsettle them, and make any computers that rely on them so error-prone that they are no longer useful.

“Even if you keep all the atoms under tight control, they can lose their quantumness by talking to their environment, heating up or interacting with things in ways you didn’t plan,” said Philipp Dumitrescu, from the Flatiron Institute’s Center for Computational Quantum Physics in New York City. “In practice, experimental devices have many sources of error that can degrade coherence after just a few laser pulses.”

Scientists need to find a way to make those qubits more robust, and less given to changing. One way has been to last them with lasers, which adds “symmetries” that make them more resilient to change – but in the new study, scientists added not one but two time symmetries, using pulses of lasers that came in order but did not repeat.

Theory suggested that this would work by creating a special arrangement in time that adds extra symmetry: meaning, in effect, that it gets a bonus amount of symmetry and resilience that it borrows from an extra dimension that doesn’t actually exist.

But theory does not always prove true in quantum computing, given the complexity and mystery of the systems. Now scientists have proven that theory right in the real world.

Scientists will now work to integrate the findings into functional computers that can rely on the perplexing behaviour to actually improve quantum computers.

“We have this direct, tantalizing application, but we need to find a way to hook it into the calculations,” Dumitrescu said in a statement. “That’s an open problem we’re working on.” 

Reference: The Independent: Andrew Griffin