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A persistent quantum computing error finally explained

Scientists have discovered the cause of a persistent glitch that continues to disrupt superconducting quantum computers, even when they have built-in defenses. For all their advanced hardware, superconducting quantum computers are vulnerable to errors caused by ionizing radiation from space or the environment. Radiation particles interfere with the chip substrate (the silicon base the processor is built on), which leads to the creation of rogue particles (quasiparticles) that disrupt the qubits, the basic units of quantum computers.

To protect against this, scientists developed a technique called gap engineering. This involves creating an energy barrier in the superconducting material of the qubits, making it harder for these particles to reach sensitive parts of the device.

However, it is not foolproof. Even with this defense, radiation can still cause sudden widespread errors affecting many qubits at once (error bursts). But it was not clear why.

Hourglass nanographenes unlock strong, robust multi-spin entanglement

Researchers from the National University of Singapore (NUS) and collaborators have developed a predictive design strategy for creating graphene-like molecules with multiple interacting spins and enhanced resilience to magnetic perturbations, opening new avenues for molecular-scale quantum information technologies and next-generation spintronics.

The research team was led by Professor Lu Jiong from the NUS Department of Chemistry and the NUS Institute for Functional Intelligent Materials, together with Professor Wu Jishan from the NUS Department of Chemistry, and international collaborators, including key contributor Professor Pavel Jelínek from the Czech Academy of Sciences in Prague.

Magnetic nanographenes, which are molecules composed of fused benzene rings, are of growing interest for quantum technologies because they can host unpaired electrons, or spins, that may be used to store and process information. Unlike conventional magnetic materials based on metal atoms, these carbon-based systems offer chemical versatility and long spin coherence times. However, engineering a single molecule that contains multiple strongly coupled spins in a stable and controlled manner remains a major challenge.

Quantum geometry applied to light-based systems expands toolkit for topological photonics

Quantum geometry describes quantum states in systems with changing system parameters, such as an electron spinning in a magnetic field whose direction is slowly changing. The state of the electron evolves, and this change is quantified by what is known as the quantum geometric distance.

With the help of this abstract geometric description, it is possible, for example, to explain superconductivity—defined as the resistance-free conduction of current—in exotic quantum materials. Another example can be found in quantum metrology: by applying quantum geometry, fundamental limits on measurement accuracy can be determined.

Copenhagen interpretation

Other articles where Copenhagen interpretation is discussed: Solvay Conferences: …be known as the “Copenhagen interpretation” of quantum mechanics, which postulated that the indeterminacy in the theory (i.e., that only the probability of a result could be predicted) was fundamental and should be accepted by scientists. There was no underlying deterministic order to be found. Some physicists, most notably…

How controlling light inside a tiny resonator could speed AI chips and secure communications

A new technology allows light to be “designed” into desired forms, potentially making AI and communication technologies faster and more accurate. A KAIST research team has developed an “integrated photonic resonator”—a core component of next-generation optical integrated circuits that process data using light. Interestingly, the research was led by an undergraduate student. This technology is expected to serve as a key foundation for next-generation security technologies such as highspeed data processing and quantum communication.

The resonator developed by the research team of Professor Sangsik Kim from the School of Electrical Engineering, in collaboration with Professor Jae Woong Yoon’s team from the Department of Physics at Hanyang University, is capable of freely controlling optical signals by utilizing light interference (the phenomenon where two light waves meet and influence each other). Their paper is published in Laser & Photonics Reviews.

Photonic Integrated Circuits (PICs) process data at ultra-high speeds and with low power consumption using light. They are garnering significant attention as a fundamental platform technology for next-generation fields such as AI, data centers, and quantum information processing.

What If Black Holes ARE Dark Energy?

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We tend to imagine there are connectings between things that we don’t understand. Quantum mechanics and consciousness, aliens and pyramids, black holes and dark matter, dark matter and dark energy, dark energy and black holes. Usually there’s no real relationship whatsoever, but this last pair—black holes and dark energy being the same thing—has received some recent hype in the press. Let’s see if it might actually be true.

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Many minds, not many worlds, constitute quantum reality

A century after the birth of quantum mechanics, many are still puzzled by the idea that Schrödinger’s cat is simultaneously alive and dead. The mystery drives some of our most prominent physicists to embrace the bizarre idea that reality constantly splits into a near infinity of parallel worlds, of which ours is just one. Philosopher of physics Nadia Blackshaw argues that this “many worlds” interpretation goes wrong not only in its extravagant multiplying of entities, but in its attempt to adopt a “view from nowhere,” describing reality from no particular perspective. She proposes instead a “many minds” interpretation, in which the cat is alive from one perspective and dead from another. It’s time physics took conscious perspectives seriously.

Sean Carroll, CalTech, John’s Hopkins, Santa Fe Institute

One of the great intellectual achievements of the twentieth century was the theory of quantum mechanics, according to which observational results can only be predicted probabilistically rather than with certainty. Yet, after decades in which the theory has been successfully used on an everyday basis, most physicists would agree that we still don’t truly understand what it means. Sean Carroll will discuss the source of this puzzlement, and explain why an increasing number of physicists are led to an apparently astonishing conclusion: that the world we experience is constantly branching into different versions, representing the different possible outcomes of quantum measurements. This could have important consequences for quantum gravity and the emergence of spacetime.

Sean Carroll is a research professor at CalTech, Homewood Professor of Natural Philosophy at John’s Hopkins University, and Fractal Faculty at SFI. His research focuses on fundamental physics and cosmology, quantum gravity and spacetime, philosophy of science, and the evolution of entropy and complexity. He’s authored “Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime;” “The Big Picture;” “The Particle at the End of the Universe;” “From Eternity to Here;” and the textbook “Spacetime and Geometry.”

Scientists just created exotic new forms of matter that shouldn’t exist

A new quantum physics study reveals that simply changing a magnetic field over time can unlock entirely new forms of matter that don’t exist under normal conditions. By carefully “driving” materials with timed magnetic shifts, researchers created exotic quantum states that could be far more stable and resistant to errors—one of the biggest challenges in quantum computing. This breakthrough suggests that the future of quantum technology may depend not just on what materials are made of, but how they’re manipulated in time.

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