Lifeboat Foundation

The experiment seeks to answer fundamental questions about experimental physics.

Ten years ago, scientists announced the discovery of the Higgs boson, which helped explain why the smallest building blocks of nature have mass. For particle physicists around the world, it was a very important and long-awaited result that marked a new era of experimental physics. Physicists at the Large Hadron Collider — the world’s largest and most powerful particle accelerator — located at the European Organization for Nuclear Research (CERN) in Geneva discovered the Higgs boson largely due to results from the ATLAS experiment.

The largest general-purpose particle detector experiment at the Large Hadron Collider, ATLAS was one of the two LHC experiments involved in the discovery of the Higgs boson in July 2012.

Human space exploration has had its share of successes, with our probes going far into interstellar space. But humans themselves haven’t made it past the Moon yet. If we’re ever to find other Earth-like planets or alien civilizations we have to be able to traverse the immense span of space much quicker. One potential invention that could make this a reality is a theoretical space drive known as the “Bussard collector” or “Ramjet propulsion”. A recent physics paper published in the journal Acta Astronautica considers the feasibility of this technology.

The thrust from the jet would theoretically allow the ship to reach relativistic speeds, while carrying no onboard fuel. The concept is based on the presence of high-energy particles in space, with hydrogen especially existing in an ionized state that can be affected by magnetic fields.

A new technique makes it possible to capture videos of single atoms “swimming” at the interface between a solid and a liquid for the first time. The approach uses stacks of two-dimensional materials to trap the liquid, making it compatible with characterization techniques that usually require vacuum conditions. It could enable researchers to better understand how atoms behave at these interfaces, which play a crucial role in devices such as batteries, catalytic systems and separation membranes.

Several techniques exist to image single atoms, including scanning tunnelling microscopy (STM) and transmission electron microscopy (TEM). However, they involve exposing atoms on the surface of the sample to a high-vacuum environment, which can change the material’s structure. Techniques that do not require a vacuum, meanwhile, are either lower-resolution or only work for short time periods, meaning that the atoms’ motion cannot be captured on video.

Researchers led by materials scientists Sarah Haigh of the University of Manchester’s National Graphene Institute (NGI) have now developed a new approach that enables them to track the motion of single atoms on a surface when that surface is surrounded by liquid. They showed that the atoms behave very differently under these circumstances than they do in vacuum. “This is crucial,” explains Haigh, “since we want to understand atomic behaviour for realistic reaction/environmental conditions that the material will experience in use – for example, in a battery, supercapacitor and membrane reaction vessels.”

Some of us, when we hear the word quantum (plural quanta, from the German word Quanten), might think of health supplements, a sports car, or even the television show Quantum Leap. More recently, in Marvel Studios movies such as Ant-Man, Doctor Strange, and Avengers: Endgame, “the quantum realm” is presented where time flows differently from our ordinary reality and the Avengers may use the subatomic world “to go back in time”, a world that “is smaller than a single atom” (Woodward, 2019, para.20)

We might have also seen or known the meaning of words such as quantum mechanics, quantum computing, and quantum entanglement, but what is a quantum and how does it relate to our ordinary realm?

A quantum is a word that refers to “how much”; it is a specific amount. For example, if the speed of your car happens to be quantized in increments of 10 mph, then as you accelerate your car from 10 mph, the speed will jump to 20 mph, without passing through any speed between 10 mph and 20 mph. A speed of 12 mph or 19 mph is excluded because the speed of your car can only exist in those increments of 10 mph.

We present a universal theory of quantum work statistics in generic disordered non-interacting Fermi systems, displaying a chaotic single-particle spectrum captured by random matrix theory. We…

The atoms arranged in lines and sheets reached about 1.2 nanokelvin, more than 2 billion times colder than interstellar space. For the atoms in three-dimensional arrangements, the situation is so complex that the researchers are still figuring out the best way to measure the temperature.

The atoms in the experiment belong to a larger group called fermions and were “the coldest fermions in the universe”, says Hazzard. “Thinking about experimenting on this 10 years ago, it looked like a theorist’s dream,” he says.

Physicists have long been interested in how atoms interact in exotic magnets like this because they suspect that similar interactions happen in high-temperature superconductors – materials that perfectly conduct electricity. By better understanding what happens, they could build better superconductors.

A team of Japanese and US physicists has pushed thousands of Ytterbium atoms to just within a billionth of a degree above absolute zero to understand how matter behaves at these extreme temperatures. The approach treats the atoms as fermions, the type of particles like electrons and protons, that cannot end up in the so-called fifth state of matter at those extreme temperatures: a Bose-Einstein Condensate.

When fermions are actually cooled down, they do exhibit quantum properties in a way that we can’t simulate even with the most powerful supercomputer. These extremely cold atoms are placed in a lattice and they simulate a “Hubbard model” which is used to study the magnetic and superconductive behavior of materials, in particular the collective motion of electrons through them.

The symmetry of these models is known as the special unitary group, or, SU, and depends on the possible spin state. In the case of Ytterbium, that number is 6. Calculating the behavior of just 12 particles in a SU Hubbard model can’t be done with computers. However, as reported in Nature Physics, the team used laser cooling to reduce the temperature of 300,000 atoms to a value almost three billion times colder than the temperature of outer space.

Be it magnets or superconductors, materials are known for their various properties. However, these properties may change spontaneously under extreme conditions. Researchers at the Technische Universität Dresden (TUD) and the Technische Universität München (TUM) have discovered an entirely new type of these phase transitions. They display the phenomenon of quantum entanglement involving many atoms, which previously has only been observed in the realm of a few atoms. The results were recently published in the scientific journal Nature.

New fur for the quantum cat

In physics, Schroedinger’s cat is an allegory for two of the most awe-inspiring effects of quantum mechanics: entanglement and superposition. Researchers from Dresden and Munich have now observed these behaviors on a much larger scale than that of the smallest of particles. Until now, materials that display properties, like magnetism, have been known to have so-called domains—islands in which the materials properties are homogeneously either of one or a different kind (imagine them being either black or white, for example).

Protons are particles that exist in the nucleus of all atoms, with their number defining the elements themselves. Protons, however, are not fundamental particles. Rather, they are composite particles made up of smaller subatomic particles, namely two “up quarks” and one “down quark” bound together by force-carrying particles (bosons) called “gluons.”

This structure isn’t certain, however, and quantum physics suggests that along with these three quarks, other particles should be “popping” into and out of existence at all times, affecting the mass of the proton. This includes other quarks and even quark-antiquark pairs.

Indeed, the deeper scientists have probed the structure of the proton with high-energy particle collisions, the more complicated the situation has become. As a result, for around four decades, physicists have speculated that protons may host a heavier form of quark than up and down quarks called “intrinsic charm quarks,” but confirmation of this has been elusive.