In recent years, physicists and engineers have developed increasingly sophisticated instruments to study particles and the interactions between them with high precision. These instruments, which include particle detectors, sensors and accelerometers, could help researchers to study physical processes in greater detail, potentially contributing to interesting new discoveries.
Scientists from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have created the first-ever atomic movies showing how atoms rearrange locally within a quantum material as it transitions from an insulator to a metal. With the help of these movies, the researchers discovered a new material phase that settles a yearslong scientific debate and could facilitate the design of new transitioning materials with commercial applications.
Despite its immense success in describing the fundamental building blocks of matter and their interactions, the Standard Model of particle physics is known to be incomplete. Experiments around the globe and in space are therefore searching for signs of new physics phenomena that would guide physicists towards a more comprehensive theory.
In most neutral-atom quantum computers, atoms are held in arrays of optical tweezers. Researchers typically populate the arrays stochastically, meaning that whether a given site receives an atom is down to chance. Atoms can later be rearranged individually, but the total number of atoms depends on the success of the initial loading.
The Atom Computing team developed an iterative process to fill an array to capacity. Instead of filling the array directly, the researchers first stochastically populated a second “reservoir” array. They then transferred atoms one by one from this reservoir to the target array using an optical tweezer. Between each loading step, the researchers imaged both arrays to determine which sites in each array were occupied. This step required temporarily switching off the tweezers and holding the atoms in an optical lattice formed from interfering laser beams.
The researchers showed that this sequence could be repeated as many times as necessary without losing atoms from the target array. They also showed that they could limit atom loss during the imaging step by enhancing the lattice strength using optical cavities. This enhancement allowed the atoms to be more strongly confined without increasing the optical lattice’s laser-power requirements.
Experiments show that effect doesn’t always follow cause in the weird world of subatomic particles, offering fresh clues about the quantum origins of space-time.
“We discovered that the glass beads in the Chang’e-5 lunar soil can preserve iron particles of different sizes, from about 1 nanometer to 1 micrometer,” said Prof. Bai.
“It is generally difficult to distinguish npFe0 of different origins observed together in single samples. Here we used the rotation feature of the impact glass beads to clearly distinguish npFe0 formed before and after the solidification of the host glass beads.”
In this study, the scientists found numerous discrete large npFe0, tens of nanometers in size, which tended to concentrate towards the extremities of the glass beads. This concentration effect can cause ultralarge npFe0 to protrude from the extremities.
Researchers at the Ye Lab at JILA (the National Institute of Standards and Technology and the University of Colorado Boulder) and University of Delaware recently created a highly precise optical lattice clock based on trapped strontium atoms. Their clock, presented in a Physical Review Letters paper, exhibits a total systematic uncertainty of 8.1 × 10–19, which is the lowest uncertainty reported to date.
New research may have found a link between supermassive black holes and dark matter particles which might solve an issue which has irked astrophysicists for decades: the “final parsec problem.”
Last year, an international team of researchers discovered a background “hum” of gravitational waves. They hypothesised that this background signal is emanating from millions of merging pairs of supermassive black hole.
Supermassive black holes are hundreds of thousands to billions of times larger than our Sun.
Claudia de Rham thinks that gravitons, hypothetical particles thought to carry gravity, have mass. If she’s right, we can expect to see “rainbows” in ripples in space-time.
A very relevant subject for research.
The world appears to contain diverse kinds of objects and systems—planets, tornadoes, trees, ant colonies, and human persons, to name but a few—characterized by distinctive features and behaviors. This casual impression is deepened by the success of the special sciences, with their distinctive taxonomies and laws characterizing astronomical, meteorological, chemical, botanical, biological, and psychological processes, among others. But there’s a twist, for part of the success of the special sciences reflects an effective consensus that the features of the composed entities they treat do not “float free” of features and configurations of their components, but are rather in some way(s) dependent on them.
Consider, for example, a tornado. At any moment, a tornado depends for its existence on dust and debris, and ultimately on whatever micro-entities compose it; and its properties and behaviors likewise depend, one way or another, on the properties and interacting behaviors of its fundamental components. Yet the tornado’s identity does not depend on any specific composing micro-entity or configuration, and its features and behaviors appear to differ in kind from those of its most basic constituents, as is reflected in the fact that one can have a rather good understanding of how tornadoes work while being entirely ignorant of particle physics.