Lifeboat Foundation

The CMS collaboration at the Large Hadron Collider (LHC) has performed the most accurate ever measurement of the mass of the top quark—the heaviest known elementary particle. The latest CMS result estimates the value of the top-quark mass with an accuracy of about 0.22%. The substantial gain in accuracy comes from new analysis methods and improved procedures to consistently and simultaneously treat different uncertainties in the measurement.

The precise knowledge of the top-quark mass is of paramount importance to understand our world at the smallest scale. Knowing this heaviest elementary particle as intimately as possible is crucial because it allows testing of the internal consistency of the mathematical description of all elementary particles, called the Standard Model.

For example, if the masses of the W boson and Higgs boson are known accurately, the top-quark mass can be predicted by the Standard Model. Likewise, using the top-quark and Higgs-boson masses, the W-boson mass can be predicted. Interestingly, despite much progress, the theoretical-physics definition of mass, which has to do with the effect of quantum-physics corrections, is still tough to pin down for the top quark.

Researchers at Dartmouth College have built the world’s first superfluid circuit that uses pairs of ultracold electron-like atoms, according to a study published in Physical Review Letters.

The laboratory test bed gives physicists control over the strength of interactions between atoms, providing a new way to explore the phenomena behind exotic materials such as superconductors.

“Much of modern technology revolves around controlling the flow of electrons around circuits,” said Kevin Wright, assistant professor of physics at Dartmouth and senior researcher of the study. “By using electron-like atoms we can test theories in ways that were not possible before.”

Circa 2015

Light behaves both as a particle and as a wave. Since the days of Einstein, scientists have been trying to directly observe both of these aspects of light at the same time. Now, scientists at EPFL have succeeded in capturing the first-ever snapshot of this dual behavior.

In a new report now published in Nature Communications Physics, Pedro R. Dieguez and an international team of scientists in quantum technologies, functional quantum systems and quantum physics, developed a new framework of operational criterion for physical reality. This attempt facilitated their understanding of a quantum system directly via the quantum state at each instance of time. During the work, the team established a link between the output visibility and elements of reality within an interferometer. The team provided an experimental proof-of-principle for a two-spin-½ system in an interferometric setup within a nuclear magnetic resonance platform. The outcomes validated Bohr’s original formulation of the complementarity principle.

Physics according to Niels Bohr

Bohr’s complementarity principle states that matter and radiation can be submitted to a unifying framework where either element can behave as a wave or a particle, based on the experimental setup. According to Bohr’s natural philosophy, the nature of individuality of quantum systems is discussed relative to the definite arrangement of whole experiments. Almost a decade ago, physicists designed a quantum delayed choice experiment (QDCE), with a beam splitter in spatial quantum superposition to render the interferometer to have a “closed + open” configuration, while the system represented a hybrid “wave + particle” state. Researchers had previously coupled a target system to a quantum regulator and tested these ideas to show how photons can exhibit wave-like or particle-like behaviors depending on the experimental technique used to measure them.

The latest results from CERN’s Large Hadron Collider have established a lower mass limit for the elusive hypothesized particle.

For the first time, scientists have managed to capture the dual natures of light – particle and wave – in a single electron microscope image.

Until now, scientists could only capture an image of light as a particle or a wave, never both at the same time. However, a team from the École Polytechnique Fédérale de Lausanne in Switzerland has overcome the challenges that previous experiments faced by imaging light in this very strange state using electrons.

Continue reading “This Is The World’s First Image of Light as Both a Particle And a Wave” »

Explaining one of astrophysics’ most puzzling particles.

Highly energetic particles called muons are ever present in the atmosphere and pass through even massive objects with ease. Sensitive detectors installed along the Tokyo Bay tunnel measure muons passing through the sea above them. This allows for changes in the volume of water above the tunnel to be calculated. For the first time, this method was used to accurately detect a mild tsunami following a typhoon in 2021.

In the time it takes you to read this sentence, approximately 100,000 muon particles will have passed through your body. But don’t worry, muons pass through ordinary matter harmlessly, and they can be extremely useful too. Professor Hiroyuki Tanaka from Muographix at the University of Tokyo has made his career out of exploring applications for muons. He’s used them to see inside volcanoes and even detect evidence of ancient earthquakes. Recently, Tanaka and his international team of researchers have turned their focus to meteorological phenomena, in particular, tsunamis.

In September 2021, a typhoon approached Japan from the south. As it neared the land it brought with it ocean swells, tsunamis. On this occasion these were quite mild, but throughout history, tsunamis have caused great damage to many coastal areas around Japan. As the huge swell moved into Tokyo Bay, something happened on a microscopic level that’s almost imperceptible. Atmospheric muon particles, generated by cosmic rays from deep space, were ever so slightly more scattered by the extra volume of water than they would be otherwise. This means the quantity of muons passing through Tokyo Bay varied as the ocean swelled.

CUORE Team Places New Limits on the Bizarre Behavior of Neutrinos Physicists are closing in on the true nature of the neutrino — and might be closer to answering a fundamental question about our own existence. In a Laboratory under a mountain, physicists are using crystals far colder than frozen air to study ghostly particles, hoping to learn secrets from the beginning of the universe. Researchers at the Cryogenic Underground Observatory for Rare Events (CUORE) announced this week that they had placed some of the most stringent limits yet on the strange possibility that the neutrino is its own antiparticle. Neutrinos are deeply unusual particles, so ethereal and so ubiquitous that they regularly pass through our bodies without us noticing. CUORE has spent the last three years patiently waiting to see evidence of a distinctive nuclear decay process, only possible if neutrinos and antineutrinos are the same particle. CUORE’s new data shows that this decay doesn’t happen for trillions of trillions of years, if it happens at all. CUORE’s limits on the behavior of these tiny phantoms are a crucial part of the search for the next breakthrough in particle and nuclear physics – and the search for our own origins.