Toggle light / dark theme

Phase transitions, like water freezing into ice, are a familiar part of our world. But in quantum systems, they can behave even more dramatically, with quantum properties such as Heisenberg uncertainty playing a central role. Furthermore, spurious effects can cause the systems to lose, or dissipate, energy to the environment. When they happen, these “dissipative phase transitions” (DPTs) push quantum systems into new states.

There are different types or “orders” of DPTs. First-order DPTs are like flipping a switch, causing abrupt jumps between states. Second-order DPTs are smoother but still transformative, changing one of the system’s global features, known as symmetry, in subtle yet profound ways.

DPTs are key to understanding how quantum systems behave in non-equilibrium conditions, where arguments based on thermodynamics often fail to provide answers. Beyond pure curiosity, this has practical implications for building more robust quantum computers and sensors. For example, second-order DPTs could enhance quantum information storage, while first-order DPTs reveal important mechanisms of system stability and control.

Many biologically important molecules change shape when stimulated by UV radiation. Although this property can also be found in some drugs, it is not yet well understood. Using an innovative technique, an international team involving researchers from Goethe University Frankfurt, the European XFEL in Schenefeld and the Deutschen Elektronen-Synchrotron DESY in Hamburg has elucidated this ultra-fast process, and made it visible in slow motion, with the help of X-ray light. The method opens up exciting new ways of analyzing many other molecules.

The study is published in the journal Nature Communications.

“We investigated the molecule 2-thiouracil, which belongs to a group of pharmaceutically active substances based on certain DNA building blocks, the nucleobases,” says the study’s last author Markus Gühr, the head of DESY’s free-electron laser FLASH and Professor of Chemistry at University of Hamburg. 2-thiouracil and its chemically related active substances have a sulfur atom, which gives the molecules its unusual, medically relevant properties.

NASA’s upcoming EZIE mission will use three small satellites to study electrojets — powerful electrical currents in the upper atmosphere linked to auroras. These mysterious currents influence geomagnetic storms that can disrupt satellites, power grids, and communication systems. By mapping how electrojets evolve, EZIE will improve space weather predictions, helping to safeguard modern technology.

Researchers from Japan and Taiwan have made a groundbreaking discovery, demonstrating for the first time that helium—long considered chemically inert—can bond with iron under extreme pressure. Using a laser-heated diamond anvil cell, they observed this unexpected interaction, suggesting that vast amounts of helium may be present in the Earth’s core. This finding challenges long-held theories about the planet’s internal structure and history and could provide new insights into the primordial nebula from which our solar system originated.

Volcanic eruptions primarily release rocks and minerals, but they can also emit traces of a rare gas known as primordial helium. Unlike the more common isotope, helium-4 (⁴He), which consists of two protons and two neutrons and is continuously produced by radioactive decay, primordial helium—helium-3 (³He)—contains only one neutron and is not formed on Earth. Its presence offers valuable clues about the planet’s deep interior and its connection to cosmic origins.

Given the occasionally high 3 He/4He ratios found in volcanic rocks, especially in Hawaii, researchers have long believed there are primordial materials containing 3 He deep within the mantle. However, graduate student Haruki Takezawa and members of Professor Kei Hirose’s group from the University of Tokyo’s Department of Earth and Planetary Science have now challenged this view with a new take on a familiar experiment — crushing things.

However, as with much of quantum physics, this “language”—the interaction between spins—is extraordinarily complex. While it can be described mathematically, solving the equations exactly is nearly impossible, even for relatively simple chains of just a few spins. Not exactly ideal conditions for turning theory into reality…

A model becomes reality

Researchers at Empa’s nanotech@surfaces laboratory have now developed a method that allows many spins to “talk” to each other in a controlled manner – and that also enables the researchers to “listen” to them, i.e. to understand their interactions. Together with scientists from the International Iberian Nanotechnology Laboratory and the Technical University of Dresden, they were able to precisely create an archetypal chain of electron spins and measure its properties in detail. Their results have now been published in the renowned journal Nature Nanotechnology.

Analysis of Moroccan stalagmites reveals that the Sahara received increased rainfall between 8,700 and 4,300 years ago, supporting early herding societies. This rainfall, likely driven by tropical plumes and monsoon expansion, narrowed the desert, improved habitability, and facilitated human movement.

Analysis of stalagmite samples from caves in southern Morocco has revealed new details about past rainfall patterns in the Sahara Desert. Researchers from the University of Oxford

The University of Oxford is a collegiate research university in Oxford, England that is made up of 39 constituent colleges, and a range of academic departments, which are organized into four divisions. It was established circa 1096, making it the oldest university in the English-speaking world and the world’s second-oldest university in continuous operation after the University of Bologna.

As Shakespeare put it, we all have our entrances and our exits on this grand stage we call life, and now researchers have identified the specific point in middle-age when our brain cells show the first signs of starting down a downward slope.

That age, based on brain scans and tests covering 19,300 individuals, is on average around 44 years. It’s here that degeneration starts to be noticeable, before hitting its most rapid rate at age 67. By the time we reach 90, the speed of brain aging levels off.

According to the team behind the new study, led by researchers from Stony Brook University in the US, the findings could be helpful in figuring out ways to promote better brain health during the later stages of life.