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Qubits 30 meters apart used to confirm Einstein was wrong about quantum

A new experiment uses superconducting qubits to demonstrate that quantum mechanics violates what’s called local realism by allowing two objects to behave as a single quantum system no matter how large the separation between them. The experiment wasn’t the first to show that local realism isn’t how the Universe works—it’s not even the first to do so with qubits.

But it’s the first to separate the qubits by enough distance to ensure that light isn’t fast enough to travel between them while measurements are made. And it did so by cooling a 30-meter-long aluminum wire to just a few milliKelvin. Because the qubits are so easy to control, the experiment provides a new precision to these sorts of measurements. And the hardware setup may be essential for future quantum computing efforts.

Jellybeans: A sweet solution for overcrowded circuitry in quantum computer chips

The silicon microchips of future quantum computers will be packed with millions, if not billions of qubits—the basic units of quantum information—to solve the greatest problems facing humanity. And with millions of qubits needing millions of wires in the microchip circuitry, it was always going to get cramped in there.

But now engineers at UNSW Sydney have made an important step toward solving a long-standing problem about giving their more breathing space—and it all revolves around jellybeans.

Not the kind we rely on for a sugar hit to get us past the 3pm slump. But jellybean quantum dots—elongated areas between qubit pairs that create more space for wiring without interrupting the way the paired qubits interact with each other.

The Roads To Zettascale And Quantum Computing Are Long And Winding

In the United States, the first step on the road to exascale HPC systems began with a series of workshops in 2007. It wasn’t until a decade and a half later that the 1,686 petaflops “Frontier” system at Oak Ridge National Laboratory went online. This year, Argonne National Laboratory is preparing for the switch to be turned on for “Aurora,” which will be either the second or the third such exascale machine in the United States, depending on the timing of the “El Capitan” system at Lawrence Livermore National Laboratory.

There were delays and setbacks on the road to exascale for all of these machines, as well as technology changes, ongoing competition with China, and other challenges. But don’t expect the next leap to zettascale – or even quantum computing – to be any quicker, according to Rick Stevens, associate laboratory director of computing for environment and life sciences at Argonne. Both could take another 15 to 20 years or more.

Such is the nature of HPC.

New Linux kernel NetFilter flaw gives attackers root privileges

A new Linux NetFilter kernel flaw has been discovered, allowing unprivileged local users to escalate their privileges to root level, allowing complete control over a system.

The CVE-2023–32233 identifier has been reserved for the vulnerability, but a severity level is yet to be determined.

The security problem stems from Netfilter nf_tables accepting invalid updates to its configuration, allowing specific scenarios where invalid batch requests lead to the corruption of the subsystem’s internal state.

Physicists create long-sought topological quantum states

The exotic particles are called non-Abelian anyons, or nonabelions for short, and their Borromean rings exist only as information inside the quantum computer. But their linking properties could help to make quantum computers less error-prone, or more ‘fault-tolerant’ — a key step to making them outperform even the best conventional computers. The results, revealed in a preprint on 9 May1, were obtained on a machine at Quantinuum, a quantum-computing company in Broomfield, Colorado, that formed as the result of a merger between the quantum computing unit of Honeywell and a start-up firm based in Cambridge, UK.

“This is the credible path to fault-tolerant quantum computing,” says Tony Uttley, Quantinuum’s president and chief operating officer.

Other researchers are less optimistic about the virtual nonabelions’ potential to revolutionize quantum computing, but creating them is seen as an achievement in itself. “There is enormous mathematical beauty in this type of physical system, and it’s incredible to see them realized for the first time, after a long time,” says Steven Simon, a theoretical physicist at the University of Oxford, UK.

UK-based tech company claims quantum computing ‘breakthrough’

Scientists at a UK-based tech company believe they are now a step closer to building a quantum computer that can solve real-world problems, after making progress towards creating a system that protects against errors.

Experts at Quantinuum said they have made a “breakthrough” towards making quantum computing fault tolerant, which would give the system the ability to continue operating without interruption, even if one or more of its components fail.

The race to build a fully functional quantum computer has mostly focused on correcting errors that affect the system, but Ilyas Khan, the company’s founder and chief product officer, said no-one has shown “an actual demonstration of a step towards qubits, the quantum equivalent of what we refer to as a ‘bit’ in existing computers, that are naturally fault tolerant”.

Physicists discover ‘stacked pancakes of liquid magnetism’

Physicists have discovered “stacked pancakes of liquid magnetism” that may account for the strange electronic behavior of some layered helical magnets.

The in the study are magnetic at cold temperatures and become nonmagnetic as they thaw. Experimental physicist Makariy Tanatar of Ames National Laboratory at Iowa State University noticed perplexing electronic behavior in layered helimagnetic crystals and brought the mystery to the attention of Rice theoretical physicist Andriy Nevidomskyy, who worked with Tanatar and former Rice graduate student Matthew Butcher to create a that simulated the quantum states of atoms and electrons in the layered materials.

Magnetic materials undergo a “thawing” transition as they warm up and become nonmagnetic. The researchers ran thousands of Monte Carlo computer simulations of this transition in helimagnets and observed how the magnetic dipoles of atoms inside the material arranged themselves during the thaw. Their results were published in a recent study in Physical Review Letters.

Entangled quantum circuits further disprove Einstein’s concept of local causality

A group of researchers led by Andreas Wallraff, Professor of Solid State Physics at ETH Zurich, has performed a loophole-free Bell test to disprove the concept of “local causality” formulated by Albert Einstein in response to quantum mechanics.

By showing that quantum mechanical objects that are far apart can be much more strongly correlated with each other than is possible in conventional systems, the researchers have provided further confirmation for . What’s special about this experiment is that the researchers were able for the first time to perform it using , which are considered to be promising candidates for building powerful quantum computers.

A Bell test is based on an experimental setup that was initially devised as a by British physicist John Bell in the 1960s. Bell wanted to settle a question that the greats of physics had already argued about in the 1930s: Are the predictions of quantum mechanics, which run completely counter to everyday intuition, correct, or do the conventional concepts of causality also apply in the atomic microcosm, as Albert Einstein believed?