Posts

Showing posts from May, 2023

Realizing the Einstein-Podolsky-Rosen Paradox for Atomic Clouds

Image
  International Conference on Nuclear Physics . In 1935, Einstein, Podolsky, and Rosen (EPR) presented an argument that they claimed implies that quantum mechanics provides an incomplete description of reality . The argument rests on two assumptions. First, if the value of a physical property of a system can be predicted with certainty, without disturbance to the system, then there is an “element of reality” to that property, meaning it has a value even if it isn’t measured. Second, physical processes have effects that act locally rather than instantaneously over a distance. John Bell subsequently proposed a way to experimentally test these “local realism” assumptions [ 2 ], and so-called Bell tests have since invalidated them for systems of a few small particles, such as electrons or photons [3]. Now Paolo Colciaghi and colleagues at the University of Basel, Switzerland, have tested EPR’s argument for a larger system comprising clouds of hundreds of atoms . Their results bring into qu

First lead-ion collisions in the LHC at record energy

Image
  International Conference on Nuclear Physics On Friday, 18 November, a test using collisions of lead ions was carried out in the LHC and provided an opportunity for the experiments to validate the new detectors and new data-processing systems ahead of next year’s lead-lead physics run. After the successful start of Run 3 in July this year, which featured proton-proton collisions at the record energy of 13.6 TeV, it was the turn of lead nuclei to circulate in the Large Hadron Collider (LHC) again last Friday after a gap of four years. Lead nuclei comprise 208 nucleons (protons and neutrons) and are used at the LHC to study quark-gluon plasma (QGP), a state of matter in which the elementary constituents, quarks and gluons, are not confined within nucleons but can move and interact over a much larger volume. In the test carried out last Friday, lead nuclei were accelerated and collided at a record energy of 5.36 TeV per nucleon-nucleon collision 1 . This is an important milestone in pre

Zeroing in on a fundamental property of the proton's internal dynamics

Image
  International Conference on Nuclear Physics Inside the proton are elementary particles called quarks. Quarks and protons have an intrinsic angular momentum called spin. Spin can point in different directions. When it is perpendicular to the proton's momentum, it is called a transverse spin. Just like the proton carries an electric charge, it also has another fundamental charge called the tensor charge. The tensor charge is the net transverse spin of quarks in a proton with transverse spin. The only way to obtain the tensor charge from experimental data is using the theory of quantum chromodynamics (QCD) to extract the "transversity" function. This universal function encodes the difference between the number of quarks with their spin aligned and anti-aligned to the proton's spin when it is in a transverse direction. Using state-of-the-art data science techniques, researchers recently made the most precise empirical determination of the tensor charge. Due to the pheno

Nuclear Reimagined: Artists Unveil New Images of Nuclear Power Ahead of IAEA Ministerial Conferenceb

Image
  International Conference on Nuclear Physics Orchids nestled by a rose-lit shore; a star birth across galaxies – these are some of the re-imaginings of nuclear power submitted in the 2022 Nuclear Power Art Contest. The images are of curiosity and wonder. The competition was launched by the grassroots, not-for-profit organisation Generation Atomic in collaboration with the IAEA and its upcoming International Ministerial Conference on Nuclear Power in the 21st Century, to challenge stereotypes and show nuclear power as a keystone of the climate change solution. The first prize was awarded to Caspian Coyle of the United States of America. Leonora Yakymashchenko of Ukraine was awarded second prize, and the third prize went to Vasily Gogidze of Georgia. “The reality is that nuclear power is stigmatized,” said Coyle, whose winning image shows the artist holding an atom and dreaming of a future that is not dictated by fear alone. “I came up against this when I first heard about nuclear power

A Revolutionary New Physics Hypothesis: Three Time Dimensions, One Space Dimension

Image
  The researchers hope that their findings will contribute to a better understanding of the phenomenon of spontaneous symmetry breaking associated with the mass of the Higgs particle and other particles in the Standard Model, particularly in the early universe. How would our world be perceived by observers moving faster than light in a vacuum? According to theorists from Warsaw and Oxford universities, such a view would differ from what we encounter daily, with the presence of not only spontaneous phenomena but also particles traveling multiple paths simultaneously. Futhermore, the very concept of time would be completely transformed — a superluminal world would have to be characterized with three time dimensions and one spatial dimension and it would have to be described in the familiar language of field theory. It turns out that the presence of such superluminal observers does not lead to anything logically inconsistent, moreover, it is quite possible that superluminal objects really

Discovery by Nuclear Physicists Challenges the Way We Understand Forces in the Universe

Image
  International Conference on Nuclear Physics A discovery by a team of researchers led by University of Massachusetts Lowell nuclear physicists could change how atoms are understood by scientists and help explain extreme phenomena in outer space. The breakthrough by the researchers revealed that a symmetry that exists within the core of atoms is not as fundamental as scientists have believed. The discovery sheds light on the forces at work within the nucleus of atoms, opening the door to a greater understanding of the universe. The findings have been published in Nature, one of the world’s premier scientific journals. The discovery was made when the UMass Lowell-led team was working to determine how atomic nuclei are created in X-ray bursts – explosions that happen on the surface of neutron stars, which are the remnants of massive stars at the end of their life. “We are studying what happens inside the nuclei of these atoms to better understand these cosmic phenomena and, ultimately, t

Physicists See ‘Strange Matter’ Form inside Atomic Nuclei

Image
  International Conference on Nuclear Physics A new physics result two decades in the making has found a surprisingly complex path for the production of strange matter within atoms. Strange matter is any matter containing the subatomic particles known as strange quarks. “Strange” here refers, in part, to a profound remoteness from our everyday lives: strange matter only seems to show up in truly extreme circumstances such as high-energy particle collisions and perhaps the enormously dense and pressurized cores of neutron stars. Probing the details of strange matter’s emergence is part of a broader effort by nuclear physicists to understand the fundamentals of how subatomic particles form. In this particular case, a group of researchers focused on one variety of strange matter, called lambda particles. “This data is the first time we study the lambda in the [atomic] nucleus, and we look at what we call hadronization, the process of producing hadrons,” says study co-author Kawtar Hafidi,

As Dense as It Gets: Using String Theory To Create a New Model for Matter

Image
  International Conference on Nuclear Physics A new model for matter in neutron star collisions. After a massive star burns its fuel and explodes as a supernova, an exceedingly compact object known as a neutron star may form. Neutron stars are very dense: to get the density within them, one would have to shrink a large body like our sun to the size of a city like Frankfurt. In 2017, gravitational waves, the small ripples in spacetime that are produced during a collision of two neutron stars, could be directly measured here on earth for the first time. However, the exact composition of the ensuing hot and dense merger product is unknown. For instance, it is currently unknown if quarks, which are normally trapped in neutrons, may emerge in free form after the collision. The Asia Pacific Center for Theoretical Physics in Pohang, South Korea, Dr. Matti Järvinen, Dr. Tuna Demircik, and Dr. Christian Ecker from the Institute for Theoretical Physics of Goethe University Frankfurt, Germany, ha

DOE nuclear physics program strategy includes Neutrinoless Double Beta Decay experiments at Wright Lab

Image
  International Conference on Nuclear Physics The U.S. Department of Energy’s (DOE) nuclear physics program is pursuing an international strategy to fund three tonne-scale experiments–CUPID, nEXO and LEGEND-1000–that are sensitive enough to search for evidence of neutrinoless double beta decay (0νββ). Wright Lab researchers, including Yale Physics professors Karsten Heeger and Reina Maruyama, and assistant professor David Moore, are involved in leading and building two out of the three experiments that will define the future of the 0νββ effort – CUPID (Heeger and Maruyama) and nEXO The search for new physics with neutrinoless double beta decay The widely accepted “standard model” of particle physics has a symmetry between matter and antimatter–whenever particles of matter are created in a laboratory, an equal number of antimatter particles are also created. However, observations show the Universe is made of matter and not antimatter, so some process in the early universe must have v

Scientists Are Hinting at The Existence of a Strange New Type of Particle

Image
  International Conference on Nuclear Physics Using one of the most powerful computers in the world to perform complex simulations, scientists have predicted a new type of dibaryon particle - one that has two baryons instead of the usual one, with quarks all of the same colour. The researchers, from the Japanese HAL QCD Collaboration, are calling the particle di-Omega. Baryons are particles that contain three quarks, the subatomic particles that are one of the fundamental constituents that make up matter, and they make up most of the normal matter in the Universe. Protons and neutrons - which make up atomic nuclei - are baryons. The charge of baryons is dependent on the "colours," or types, of the quarks inside, of which there are six - up, down, top, bottom, charm, and strange. In nature, there is only one known particle that's made up of two baryons, or a dibaryon particle (also known as a hexaquark). It's called deuteron, and it consists of a proton and a neutron b

Nuclear Physicists Use High-Energy Electron Beam To Hunt for Clues of Color Transparency in Protons

Image
  International Conference on Nuclear Physics Protons populate the nucleus of every atom in the universe. Inside the nucleus, they cling tightly to neighboring protons and neutrons. However, it may be possible to knock out protons that are in a smaller size configuration, so that they interact less with nearby particles as they exit the nucleus. This phenomenon is called color transparency. Nuclear physicists hunting for signs of color transparency in protons recently came up empty handed.   The Impact The theory that describes the behavior of particles made of quarks is called quantum chromodynamics (QCD). QCD includes many common subatomic particles, such as protons and neutrons. It also predicts the phenomenon of color transparency. Physicists have observed color transparency in simpler, two-quark particles called pions. If physicists can observe or rule out color transparency for protons, a more complicated three-quark system, they would gain important clues regarding the differe

Nuclear ‘knots’ could unravel the mysteries of atoms

Image
  International Conference on Nuclear Physics A skyrmion is a tiny disturbance in a substance, a swirling pattern that, like a knot, is difficult to undo. In the 1960s, nuclear physicist Tony Skyrme suggested that these structures — since named after him — could represent protons and neutrons within a nucleus in theoretical calculations. But despite some initial promise, the idea hit snags. In particular, skyrmion calculations produced misshapen nuclei. But now researchers have improved their calculations of how protons and neutrons should cluster together in the skyrmion picture. Those results agreed with expectations based on experimental data, the team reports in a study in press at Physical Review Letters. Here’s how the idea works: Inside a nucleus, particles called pions are constantly zinging around, helping to hold the nucleus together. Just as an electron has an electric field that can jostle other particles, those pions are associated with fields too. In Skyrme’s original pic