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Awarded the 2023 Nobel Prize in Chemistry, quantum dots have a wide variety of applications ranging from displays and LED lights to chemical reaction catalysis and bioimaging. These semiconductor nanocrystals are so small – on the order of nanometers – that their properties, such as color, are size dependent, and they start to exhibit quantum properties. This technology has been really well developed, but only in the visible spectrum, leaving untapped opportunities for technologies in both the ultraviolet and infrared regions of the electromagnetic spectrum.

In new research published in Nature Synthesis (“Interdiffusion-enhanced cation exchange for HgSe and HgCdSe nanocrystals with infrared bandgaps”), University of Illinois at Urbana-Champaign bioengineering professor Andrew Smith and postdoctoral researcher Wonseok Lee have developed mercury selenide (HgSe) and mercury cadmium selenide (HgCdSe) nanocrystals that absorb and emit in the infrared, made from already well-developed, visible spectrum cadmium selenide (CdSe) precursors. The new nanocrystal products retained the desired properties of the parent CdSe nanocrystals, including size, shape and uniformity.

“This is the first example of infrared quantum dots that are at the same level of quality as the ones that are in the visible spectrum,” Smith says.

Quantum computers offer powerful ways to improve cybersecurity, communications, and data processing, among other fields. To realize these full benefits, however, multiple quantum computers must be connected to build quantum networks or a quantum internet. Scientists have struggled to come up with practical methods of building such networks, which must transmit quantum information over long distances.

Now, researchers at the University of Chicago Pritzker School of Molecular Engineering (PME) have proposed a new approach—building long quantum channels using vacuum sealed tubes with an array of spaced-out lenses. These vacuum beam guides, about 20 centimeters in diameter, would have ranges of thousands of kilometers and capacities of more than 1,013 qubits per second, better than any existing quantum communication approach. Photons of light encoding quantum data would move through the vacuum tubes and remain focused thanks to the lenses.

“We believe this kind of network is feasible and has a lot of potential,” said Liang Jiang, professor of molecular engineering and senior author of the new work. “It could not only be used for secure communication, but also for building distributed quantum computing networks, distributed quantum sensing technologies, new kinds of telescopes, and synchronized clocks.”

Fundamental physics—let alone quantum physics—might sound complicated to many, but it can actually be applied to solve everyday problems.

Imagine navigating to an unfamiliar place. Most people would suggest using GPS, but what if you were stuck in an underground tunnel where radio signals from satellites were not able to penetrate? That’s where quantum sensing tools come in.

USC Viterbi Information Sciences Institute researchers Jonathan Habif and Justin Brown, both from ISI’s new Laboratory for Quantum-Limited Information, are working at making sensing instruments like atomic accelerometers smaller and more accurate so they can be used to navigate when GPS is down.

The Information-Theoretic Interpretation of Quantum Mechanics from (Bub & Pitowsky, 2010) has been criticized in two ways related to the ontological picture it supplies. This paper explores whether Ontic Structural Realism can supplement the metaphysics of ITIQM in a way that would satisfy its critics. The many similarities between the two views are detailed. And it is argued that the ITIQM view ca. 2010 does seem to be compatible with OSR, but as the view evolved in Bub’s Bananaworld (2016), its fundamental metaphysical commitments shifted, making it a less clean fit with OSR.

When atomic nuclei and subatomic particles interact, the results are incredibly complex. These are the “many body problems” of quantum mechanics. To help make sense of these interactions, scientists create ways to simplify the range of possible outcomes.

One example is “effective interactions,” which simplify the interactions between a (a or a neutron) and an atomic nucleus. Effective interactions help scientists develop theories of the reactions that result when nuclei collide with each other or with .

These tools are part of a group of methods called effective field theory (EFT). EFT in turn is a type of approach called “ab initio,” or “first principles.” Ab initio means a calculation starts with the established laws of physics without any other assumptions.

Around 80% of the universe’s matter is dark, meaning it is invisible. Despite being imperceptible, dark matter constantly streams through us at a rate of trillions of particles per second. We know it exists due to its gravitational effects, yet direct detection has remained elusive.

Researchers from Lancaster University, the University of Oxford, and Royal Holloway, University of London, are leveraging cutting-edge quantum technologies to build the most sensitive dark matter detectors to date. Their project, titled “A Quantum View of the Invisible Universe,” is featured at the Royal Society’s Summer Science Exhibition. Related research is also published in the Journal of Low Temperature Physics

The team includes Dr. Michael Thompson, Professor Edward Laird, Dr. Dmitry Zmeev, and Dr. Samuli Autti from Lancaster, Professor Jocelyn Monroe from Oxford, and Professor Andrew Casey from RHUL.

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How to explain our inner awareness that is at once most common and most mysterious? Traditional explanations focus at the level of neuron and neuronal circuits in the brain. But little real progress has motivated some to look much deeper, into the laws of physics — information theory, quantum mechanics, even postulating new laws of physics.

Watch more videos on consciousness as all physical: https://shorturl.at/PKpOk.

Sean Carroll is Homewood Professor of Natural Philosophy at Johns Hopkins University and fractal faculty at the Santa Fe Institute. His research focuses on fundamental physics and cosmology.