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Researchers have found a way to predict the behavior of many-body quantum systems coupled to their environment. The work represents a way to protect quantum information in quantum devices, which is crucial for real-world applications of quantum technology.

In a study published in Physical Review Letters, researchers at Aalto University in Finland and IAS Tsinghua University in China report a new way to predict how , such as groups of particles, behave when they are connected to the external environment. Usually, connecting a system such as a quantum computer to its environment creates decoherence and leaks, which ruin any information about what’s happening inside the system. Now, the researchers developed a technique that turns that problem into its a solution.

The research was carried out by Aalto doctoral researcher Guangze Chen under the supervision of Professor Jose Lado and in collaboration with Fei Song from IAS Tsinghua. Their approach combines techniques from two domains, quantum many-body physics and non-Hermitian quantum physics.

By default, every quantum computer is going to be a hybrid that combines quantum and classical compute. Microsoft estimates that a quantum computer that will be able to help solve some of the world’s most pressing questions will require at least a million stable qubits. It’ll take massive classical compute power — which is really only available in the cloud — to control a machine like this and handle the error correction algorithms needed to keep it stable. Indeed, Microsoft estimates that to achieve the necessary fault tolerance, a quantum computer will need to be integrated with a peta-scale compute platform that can manage between 10 to 100 terabits per second of data moving between the quantum and classical machine. At the American Physical Society March Meeting in Las Vegas, Microsoft today is showing off some of the work it has been doing on enabling this and launching what it calls the “Integrated Hybrid” feature in Azure Quantum.

“With this Integrated Hybrid feature, you can start to use — within your quantum applications — classical code right alongside quantum code,” Krysta Svore, Microsoft’s VP of Advanced Quantum Development, told me. “It’s mixing that classical and quantum code together that unlocks new types, new styles of quantum algorithms, prototypes, sub routines, if you will, where you can control what you do to qubits based on classical information. This is a first in the industry.”

With the rapid development of chatbots and other AI systems, questions about whether they will ever gain true understanding, become conscious, or even develop a feeling agency have become more pressing. When it comes to making sense of these qualities in humans, our ability for counterfactual thinking is key. The existence of alternative worlds where things happen differently, however, is not just an exercise in imagination – it’s a key prediction of quantum mechanics. Perhaps our brains are able to ponder how things could have been because in essence they are quantum computers, accessing information from alternative worlds, argues Tim Palmer.

Ask a chatbot “How many prime numbers are there?” and it will surely tell you that there are an infinite number. Ask the chatbot “How do we know?” and it will reply that there are many ways to show this, the original going back to the mathematician Euclid of ancient Greece. Ask the chatbot to describe Euclid’s proof and it will answer correctly [ii]. [ii.

Of course, the chatbot has got all this information from the internet. Additional software in the computer can check that each of the steps in Euclid’s proof is valid and hence can confirm that the proof is a good one. But the computer doesn’t understand the proof. Understanding is a kind of Aha! moment, when you see why the proof works, and why it wouldn’t work if a minor element in it was different (for example the proof in the footnotes doesn’t work if any number but 1 is added when creating the number Q). Chatbots don’t have Aha! moments, but we do. Why?

Glass nanoparticles trapped by lasers in extreme vacuum are considered a promising platform for exploring the limits of the quantum world. Since the advent of quantum theory, the question at which sizes an object starts being described by the laws of quantum physics rather than the rules of classical physics has remained unanswered.

A team formed by Lukas Novotny (ETH Zurich), Markus Aspelmeyer (University of Vienna), Oriol Romero-Isart (University of Innsbruck), and Romain Quidant (Zurich) is attempting to answer precisely this question within the ERC-Synergy project Q-Xtreme. A crucial step on the way to this goal is to reduce the energy stored in the motion of the nanoparticle as much as possible, i.e. to cool the particle down to the so-called quantum ground-state.

A 1960s nuclear research lab in the North of England will host a new quantum computing facility under plans drawn up by a Silicon Valley technology company.

PsiQuantum is to set up a research hub at the Daresbury Laboratory in Cheshire, using the facility’s state of the art cooling systems to develop its technology.

PsiQuantum, which is backed by BlackRock, Microsoft and Baillie Gifford, was set up by professors at the University of Bristol and Imperial College London but its founders moved to Silicon Valley in 2016 under advice from investors.

I recently speculated on a toy model for scientific theology, with superintelligent God-like entities that live in the bare quantum vacuum. More speculations below.

This is not (yet) science — it’s far too vague and speculative to be called that — or theology. Call it science fiction (or “religion fiction” in the sense explored in my article “Religion Fiction Inspires Real Religion”) without the fiction. I guess I should write a science fiction story as a container for these speculations.

Therefore, I’ll often refer to superfluid vacuum theory (SVT) as “Cooper-Hofstadter theory” — a SVT that was featured in “The Big Bang Theory” TV show, of all things! Also, I guess Sheldon Cooper is more known than Leon Cooper.

The concept of Boltzmann Brain — a self-aware entity that emerges from random fluctuations in the fabric of reality— is intriguing. Perhaps God emerges from the evolution of a cosmic society of Boltzmann Brains?

I am referring to a generic “fabric of reality” but the concept can be formulated more precisely. For example, imagine a conscious, thinking being arising from random quantum fluctuations in the vacuum.

In the delightful “The Gravity Mine” short story, Stephen Baxter imagines the birth of a Boltzmann Brain:

The smooth space-time fabric of reality seems to break down at very small scales, and become a fractal with infinite depth. New physics, with intriguing implications for metaphysics and theology, could be hidden in those fractal depths.

Smooth (continuous and differentiable) curves and surfaces become locally flat if you zoom-in deep enough. But fractals are always rough at all scales, and you can zoom-in a fractal forever.

In his seminal book “The Fractal Geometry of Nature,” Benoît Mandelbrot mentioned “a new fractal wrinkle to the presentation of quantum mechanics.”

Since the advent of quantum mechanics, the field of physics has been divided into two distinct areas: classical physics and quantum physics. Classical physics deals with the movements of everyday objects in the macroscopic world, while quantum physics explains the strange behaviors of tiny elementary particles in the microscopic world.

Many solids and liquids are made up of particles that interact with each other at close distances, leading to the creation of “quasiparticles.” Quasiparticles are stable excitations that act as weakly interacting particles. The concept of quasiparticles was introduced in 1941 by Soviet physicist Lev Landau and has since become a crucial tool in the study of quantum matter. Some well-known examples of quasiparticles include Bogoliubov quasiparticles in superconductivity, excitons in semiconductors.

Semiconductors are a type of material that has electrical conductivity between that of a conductor (such as copper) and an insulator (such as rubber). Semiconductors are used in a wide range of electronic devices, including transistors, diodes, solar cells, and integrated circuits. The electrical conductivity of a semiconductor can be controlled by adding impurities to the material through a process called doping. Silicon is the most widely used material for semiconductor devices, but other materials such as gallium arsenide and indium phosphide are also used in certain applications.