An international collaboration of scientists has created and observed an entirely new class of vortices—the whirling masses of fluid or air.
Led by researchers from Amherst College in the U.S. and the University of East Anglia and Lancaster University in the U.K., their new paper details the first laboratory studies of these “exotic” whirlpools in an ultracold gas of atoms at temperatures as low as tens of billionths of a degree above absolute zero.
The discovery, announced this week in the journal Nature Communications, may have exciting future implications for implementations of quantum information and computing.
A team based at Princeton University has accurately simulated the initial steps of ice formation by applying artificial intelligence (AI) to solving equations that govern the quantum behavior of individual atoms and molecules.
The resulting simulation describes how water molecules transition into solid ice with quantum accuracy. This level of accuracy, once thought unreachable due to the amount of computing power it would require, became possible when the researchers incorporated deep neural networks, a form of artificial intelligence, into their methods. The study was published in the journal Proceedings of the National Academy of Sciences.
“In a sense, this is like a dream come true,” said Roberto Car, Princeton’s Ralph W. *31 Dornte Professor in Chemistry, who co-pioneered the approach of simulating molecular behaviors based on the underlying quantum laws more than 35 years ago. “Our hope then was that eventually we would be able to study systems like this one, but it was not possible without further conceptual development, and that development came via a completely different field, that of artificial intelligence and data science.”
Topology and entanglement are two powerful principles for characterizing the structure of complex quantum states. In a new paper in the journal Physical Review X, researchers from the University of Pennsylvania establish a relationship between the two.
“Our work ties two big ideas together,” says Charles Kane, the Christopher H. Browne Distinguished Professor of Physics in Penn’s School of Arts & Sciences. “It’s a conceptual link between topology, which is a way of characterizing the universal features that quantum states have, and entanglement, which is a way in which quantum states can exhibit non-local correlations, where something that happens in one point in space is correlated with something that happens in another part in space. What we’ve found is a situation where those concepts are tightly intertwined.”
The seed for exploring this connection came during the long hours Kane spent in his home office during the pandemic, pondering new ideas. One train of thought had him envisioning the classic textbook image of the Fermi surface of copper, which represents the metal’s potential electron energies. It’s a picture every physics student sees, and one with which Kane was highly familiar.
An international research team led by the University of Göttingen has detected novel quantum effects in high-precision studies of natural double-layer graphene and has interpreted them together with the University of Texas at Dallas using their theoretical work. This research provides new insights into the interaction of the charge carriers and the different phases, and contributes to the understanding of the processes involved. The LMU in Munich and the National Institute for Materials Science in Tsukuba, Japan, were also involved in the research. The results were published in Nature.
The novel material graphene, a wafer-thin layer of carbon atoms, was first discovered by a British research team in 2004. Among other unusual properties, graphene is known for its extraordinarily high electrical conductivity. If two individual graphene layers are twisted at a very specific angle to each other, the system even becomes superconducting (i.e. conducts electricity without any resistance) and exhibits other exciting quantum effects such as magnetism. However, the production of such twisted graphene double-layers has so far required increased technical effort.
This novel study used the naturally occurring form of double-layer graphene, where no complex fabrication is required. In a first step, the sample is isolated from a piece of graphite in the laboratory using a simple adhesive tape. To observe quantum mechanical effects, the Göttingen team then applied a high electric field perpendicular to the sample: the electronic structure of the system changes and a strong accumulation of charge carriers with similar energy occurs.
Electrons inhabit a strange and topsy-turvy world. These infinitesimally small particles have never ceased to amaze and mystify despite the more than a century that scientists have studied them. Now, in an even more amazing twist, physicists have discovered that, under certain conditions, interacting electrons can create what are called ‘topological quantum states.’ This finding, which was recently published in the journal Nature, has implications for many technological fields of study, especially information technology.
Topological states of matter are particularly intriguing classes of quantum phenomena. Their study combines quantum physics with topology, which is the branch of theoretical mathematics that studies geometric properties that can be deformed but not intrinsically changed. Topological quantum states first came to the public’s attention in 2016 when three scientists—Princeton’s Duncan Haldane, who is Princeton’s Thomas D. Jones Professor of Mathematical Physics and Sherman Fairchild University Professor of Physics, together with David Thouless and Michael Kosterlitz—were awarded the Nobel Prize for their work in uncovering the role of topology in electronic materials.
“The last decade has seen quite a lot of excitement about new topological quantum states of electrons,” said Ali Yazdani, the Class of 1909 Professor of Physics at Princeton and the senior author of the study. “Most of what we have uncovered in the last decade has been focused on how electrons get these topological properties, without thinking about them interacting with one another.”
Circa 2021 This gets very close to a master algorithm for math and helps with quantum computing too.
Abstract. Humans carrying the CORD7 (cone-rod dystrophy 7) mutation possess increased verbal IQ and working memory. This autosomal dominant syndrome is caused b.
When Carnegie Mellon University doctoral candidates I-Hsuan Kao and Ryan Muzzio started working together a switch flicked on. Then off.
Working in the Department of Physics’ Lab for Investigating Quantum Materials, Interfaces and Devices (LIQUID) Group, Kao, Muzzio and other research partners were able to show proof of concept that running an electrical current through a novel two-dimensional material could control the magnetic state of a neighboring magnetic material without the need of applying an external magnetic field.
The groundbreaking work, which was published in Nature Materials in June and has a related patent pending, has potential applications for data storage in consumer products such as digital cameras, smartphones and laptops.
In Einstein’s theory of general relativity, gravity arises when a massive object distorts the fabric of spacetime the way a ball sinks into a piece of stretched cloth. Solving Einstein’s equations by using quantities that apply across all space and time coordinates could enable physicists to eventually find their “white whale”: a quantum theory of gravity.
In a new article in The European Physical Journal H 0, Donald Salisbury from Austin College in Sherman, USA, explains how Peter Bergmann and Arthur Komar first proposed a way to get one step closer to this goal by using Hamilton-Jacobi techniques. These arose in the study of particle motion in order to obtain the complete set of solutions from a single function of particle position and constants of the motion.
Three of the four fundamental forces —strong, weak, and electromagnetic—hold under both the ordinary world of our everyday experience, modeled by classical physics, and the spooky world of quantum physics. Problems arise, though, when trying to apply to the fourth force, gravity, to the quantum world. In the 1960s and 1970s, Peter Bergmann of Syracuse University, New York and his associates recognized that in order to someday reconcile Einstein’s theory of general relativity with the quantum world, they needed to find quantities for determining events in space and time that applied across all frames of reference. They succeeded in doing this by using the Hamilton-Jacobi techniques.
Simulations of a quantum computer made of six rubidium atoms suggest it could run a simple brain-inspired algorithm that can learn to remember and make simple decisions.
