Mathematicians have discovered a approach to rework an unproductive quantum computing method by reviving a category of beforehand discarded particles.
Quantum computer systems can remedy issues past the capabilities of classical computer systems by utilizing rules like superposition. This means a quantum bit, or qubit, can characterize each 0 and 1 concurrently, just like the well-known thought experiment of a cat being each lifeless and alive. But qubits are extraordinarily fragile. Interactions with the atmosphere can simply disrupt their quantum states. Their fragility makes it tough to construct steady quantum computer systems.
Ising anyons exist only in two-dimensional systems. They are at the heart of topological quantum computing. It means that anyons store information not in the particles themselves, but in how they loop or braid around one another. That braiding can encode and process information in ways that are far more resistant to environmental noise.
But there’s been a major limitation. “The only problem with Ising anyons is that they are not universal,” Aaron Lauda, a professor of physics and arithmetic on the University of Southern California, advised Live Science. “It’s like when you might have a keyboard and it solely has half the keys.”
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That’s where the overlooked math comes in. The team revisited a class of theories called “non-semisimple topological quantum area principle,” is used to review symmetry in mathematical objects.
“This is a key concept in particle physics,” Lauda said. “You’re in a position to predict new particles that individuals did not find out about simply by understanding the symmetry of what occurs.”
In this theory, each particle has a quantum dimension — a number that reflects how much “weight,” or influence, it has in the system. If the number is zero, the particle is usually discarded.
“The key concept of those new non-semisimple variations is that you simply preserve these particles, which initially had zero weight,” Lauda told Live Science. “And you give you a brand new manner of measuring the load. There are some properties that it has to fulfill, and work out the way to make that quantity not be zero.”
The neglected pieces, reinterpreted as particles, filled in the missing capabilities of Ising anyons. The team showed that with just one neglecton added to the system, the particle becomes capable of universal computation just through braiding.
Why do Ising anyons matter?
To see why anyons matter in any respect, it helps to grasp their peculiar habits in two dimensions.
In three dimensions, particles like bosons and fermions can loop around each other. But those loops can be undone, like slipping a string over or under another. In two dimensions, by contrast, there’s no “over” or “under.” That means when anyons move around one another, the paths can’t be untangled, giving rise to fundamentally new physics.
“The way to think about it,” Lauda explained, “is if I start with a state zero and I wrap it around, does it stay in a state zero or some multiple of that? Or does it create a zero and a one? Am I able to mix them and create these superpositions that I need to do quantum computation?”
The key with Ising anyons is to be able to create superpositions. Because these operations depend on the overall shape of the braiding path, rather than on precise locations, they’re naturally shielded from many kinds of noise.
The finding doesn’t mean we’ll have topological quantum computers tomorrow. But it suggests that rather than inventing entirely new materials or exotic particles, researchers may just need to look at familiar systems through a new mathematical lens.