Lifeboat Foundation

Very recently, researchers led by Markus Aspelmeyer at the University of Vienna and Lukas Novotny at ETH Zurich cooled a glass nanoparticle into the quantum regime for the first time. To do this, the particle is deprived of its kinetic energy with the help of lasers. What remains are movements, so-called quantum fluctuations, which no longer follow the laws of classical physics but those of quantum physics. The glass sphere with which this has been achieved is significantly smaller than a grain of sand, but still consists of several hundred million atoms. In contrast to the microscopic world of photons and atoms, nanoparticles provide an insight into the quantum nature of macroscopic objects. In collaboration with experimental physicist Markus Aspelmeyer, a team of theoretical physicists led by Oriol Romero-Isart of the University of Innsbruck and the Institute of Quantum Optics and Quantum Information of the Austrian Academy of Sciences is now proposing a way to harness the quantum properties of nanoparticles for various applications.

Briefly delocalized

“While atoms in the motional ground state bounce around over distances larger than the size of the atom, the motion of macroscopic objects in the ground state is very, very small,” explain Talitha Weiss and Marc Roda-Llordes from the Innsbruck team. “The quantum fluctuations of nanoparticles are smaller than the diameter of an atom.” To take advantage of the quantum nature of nanoparticles, the wave function of the particles must be greatly expanded. In the Innsbruck quantum physicists’ scheme, nanoparticles are trapped in optical fields and cooled to the ground state. By rhythmically changing these fields, the particles now succeed in briefly delocalizing over exponentially larger distances. “Even the smallest perturbations may destroy the coherence of the particles, which is why by changing the optical potentials, we only briefly pull apart the wave function of the particles and then immediately compress it again,” explains Oriol Romero-Isart.

When gravitational waves were first detected in 2015 by the advanced Laser Interferometer Gravitational-Wave Observatory (LIGO), they sent a ripple through the scientific community, as they confirmed another of Einstein’s theories and marked the birth of gravitational wave astronomy. Five years later, numerous gravitational wave sources have been detected, including the first observation of two colliding neutron stars in gravitational and electromagnetic waves.

As LIGO and its international partners continue to upgrade their detectors’ sensitivity to gravitational waves, they will be able to probe a larger volume of the universe, thereby making the detection of gravitational wave sources a daily occurrence. This discovery deluge will launch the era of precision astronomy that takes into consideration extrasolar messenger phenomena, including electromagnetic radiation, gravitational waves, neutrinos and cosmic rays. Realizing this goal, however, will require a radical re-thinking of existing methods used to search for and find gravitational waves.

Recently, computational scientist and lead for translational artificial intelligence (AI) Eliu Huerta of the U.S. Department of Energy’s (DOE) Argonne National Laboratory, in conjunction with collaborators from Argonne, the University of Chicago, the University of Illinois at Urbana-Champaign, NVIDIA and IBM, has developed a new production-scale AI framework that allows for accelerated, scalable and reproducible detection of gravitational waves.

Watch as the blast wave from an exploded star moves at nearly 9 million miles per hour. Astronomers captured this movement by combining data spanning 14 years from NASA’s Chandra X-ray Observatory. This hand-shaped structure is a nebula of energy and particles blown by a pulsar left behind aft.

Finding the hypothetical particle axion could mean finding out for the first time what happened in the Universe a second after the Big Bang, suggests a new study published in Physical Review D.

How far back into the Universe’s past can we look today? In the electromagnetic spectrum, observations of the Cosmic Microwave Background — commonly referred to as the CMB — allow us to see back almost 14 billion years to when the Universe cooled sufficiently for protons and electrons to combine and form neutral hydrogen. The CMB has taught us an inordinate amount about the evolution of the cosmos, but photons in the CMB were released 400000 years after the Big Bang making it extremely challenging to learn about the history of the universe prior to this epoch.

To open a new window, a trio of theoretical researchers, including Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) Principal Investigator, University of California, Berkeley, MacAdams Professor of Physics and Lawrence Berkeley National Laboratory senior faculty scientist Hitoshi Murayama, Lawrence Berkeley National Laboratory physics researcher and University of California, Berkeley, postdoctoral fellow Jeff Dror (now at University of California, Santa Cruz), and UC Berkeley Miller Research Fellow Nicholas Rodd, looked beyond photons, and into the realm of hypothetical particles known as axions, which may have been emitted in the first second of the Universe’s history.

The event produced a short-lived particle known as a W boson and proved a 60-year-old theory.

The scientists studied fermion masses which they are of the belief that can be communicated into the fifth dimension through portals, forming dark matter relics and ‘fermionic dark matter’ within the novel fifth dimension.

Researchers said in a statement to Vice, “We found that the new scalar field had an interesting, non-trivial behaviour along the extra dimension. If this heavy particle exists, it would necessarily connect the visible matter that we know and that we have studied in detail with the constituents of dark matter, assuming the dark matter is composed out of fundamental fermions, which live in the extra dimension.”

They refer to the particle as a potential messenger to the dark sector. But hypothesising is not as hard as actually looking for the particle. If you didn’t know, the Higgs Boson Particle which was discovered in 2012 and also rewarded the discoverer with a Nobel Prize, was first proposed sometime in 1964. It was only discovered after the construction of the Large Hadron Collider — world’s most powerful particle accelerator.

Physics-informed machine learning might help verify microchips.

Physicists love recreating the world in software. A simulation lets you explore many versions of reality to find patterns or to test possibilities. But if you want one that’s realistic down to individual atoms and electrons, you run out of computing juice pretty quickly.

Machine-learning models can approximate detailed simulations, but often require lots of expensive training data. A new method shows that physicists can lend their expertise to machine-learning algorithms, helping them train on a few small simulations consisting of a few atoms, then predict the behavior of system with hundreds of atoms. In the future, similar techniques might even characterize microchips with billions of atoms, predicting failures before they occur.

Continue reading “Physicists Teach AI to Simulate Atomic Clusters” »

Researchers at ETH Zurich have succeeded in observing a crystal that consists only of electrons. Such Wigner crystals were already predicted almost ninety years ago but could only now be observed directly in a semiconductor material.

Crystals have fascinated people through the ages. Who hasn’t admired the complex patterns of a snowflake at some point, or the perfectly symmetrical surfaces of a rock crystal? The magic doesn’t stop even if one knows that all this results from a simple interplay of attraction and repulsion between atoms and electrons. A team of researchers led by Ataç Imamoğlu, professor at the Institute for Quantum Electronics at ETH Zurich, have now produced a very special crystal. Unlike normal crystals, it consists exclusively of electrons. In doing so, they have confirmed a theoretical prediction that was made almost ninety years ago and which has since been regarded as a kind of holy grail of condensed matter physics. Their results were recently published in the scientific journal Nature.

Researchers at ETH Zurich have succeeded in observing a crystal that consists only of electrons. Such Wigner crystals were already predicted almost ninety years ago but could only now be observed directly in a semiconductor material.

Crystals have fascinated people through the ages. Who hasn’t admired the complex patterns of a snowflake at some point, or the perfectly symmetrical surfaces of a rock crystal? The magic doesn’t stop even if one knows that all this results from a simple interplay of attraction and repulsion between atoms and electrons. A team of researchers led by Ataç Imamoğlu, professor at the Institute for Quantum Electronics at ETH Zurich, have now produced a very special crystal. Unlike normal crystals, it consists exclusively of electrons. In doing so, they have confirmed a theoretical prediction that was made almost ninety years ago and which has since been regarded as a kind of holy grail of condensed matter physics. Their results were recently published in the scientific journal Nature.

A decades-old prediction

Continue reading “A Crystal Made Exclusively of Electrons – ‘Holy Grail’ Wigner Crystals Observed for First Time” »