All articles tagged with #phase transition
A Nature Physics study used an unsupervised AI trained on 74 million simulated water configurations to uncover two distinct molecular arrangements in liquid water—Structure A dense and disordered, Structure B light and ordered—that continually swap across various temperatures and pressures. This supports the long-suspected two-structure theory and paves the way for experimental validation of water’s dual structure.
Ars Technica's May roundup surveys a range of science stories: evidence suggesting prehistoric copper smelting at a Pyrenees site based on malachite-bearing hearths; the description of Microeledone galapagensis, a newly identified tiny blue octopus; comparisons of slapsticks' acoustics; a topological analysis differentiating real abstract art from AI-generated work; and a physics-inspired view of political polarization as a phase transition driven by campaign spending, alongside the finding that cats preferentially respond to silver vine over catnip.
Scientists confirmed two new, highly complex ice phases—ice XXI with a 152-molecule repeat and ice XXII with a 304-molecule repeat—supporting Ostwald’s step rule and highlighting how water’s solid forms can impact pharmaceutical crystallization and materials science.
Stockholm University researchers used ultra-fast X-ray lasers to observe a hidden liquid-liquid critical point in deeply supercooled water at about -63°C and 1000 atmospheres, showing how two liquid forms merge at the critical point and clarifying water’s unusual density and other anomalies; beyond this point, water becomes supercritical.
Scientists in Japan discovered that when confined to tiny spaces, water can simultaneously exhibit properties of both a solid and a liquid, a state called premelting, especially observed in heavy water within nanostructures, revealing new insights into water's complex behavior and potential applications.
Researchers successfully superheated solid gold to over 14 times its melting point for a brief moment, bypassing the entropy catastrophe limit, which could lead to new insights into phase transitions and material production. Using ultrafast laser heating on nanoscale gold films, they achieved this extreme state without the usual structural breakdown, opening possibilities for advanced material manipulation.
The question of whether the end of our Universe will mirror its beginning through a new Big Bang triggered by dark energy remains unanswered. Cosmic inflation, which set up the hot Big Bang, ended in a second-order phase transition, while vacuum decay scenarios rely on first-order phase transitions, suggesting fundamental differences. Although dark energy and inflation may be related, any discussion of a future vacuum decay scenario remains speculative, with no evidence to validate it. The possibility of such a scenario occurring is open, but firmly in the realm of pure speculation at this point.
Researchers from the University of California, Santa Barbara, have discovered a spin microemulsion phase in two-dimensional systems of spinor Bose-Einstein condensates. This phase transition is characterized by the loss of superfluidity, complex pseudospin textures, and the emergence of topological defects. The spin microemulsion phase occurs when the motion of each atom is coupled to its internal spin state, resulting in a spin-orbit coupling effect. The findings provide insights into the behavior of two-dimensional systems and have implications for both quantum physics and soft matter systems. Future research will focus on investigating the thermodynamic stability of the spin microemulsion and its response to different system parameters.
Physicists have successfully observed and measured an "unobservable" quantum phase transition, thanks to advancements in quantum computing. Using clever techniques and the brute-force power of quantum computers, researchers were able to detect and study the entanglement structure of chains of qubits, providing evidence for the existence of entanglement filling the chain. This breakthrough has sparked interest in the role of measurements in generating new phenomena and has opened up new possibilities for manipulating and supercharging entangled states of quantum matter.
This week's Phys.org highlights include the discovery of an ancient water management system in China built without centralized authority, the detection of a hidden phase of matter that separates supercooled liquids from normal liquids, the New Horizons spacecraft measuring the darkness of the universe, extreme coral reef bleaching off southeast Florida due to rising ocean temperatures, and a study showing that the top 10% of wealth holders in the US are responsible for 40% of carbon emissions, suggesting that the tax code could be used to address climate change.
Scientists at Lawrence Berkeley National Laboratory have proposed a theory explaining the molecular behavior of supercooled liquids, which represents a hidden phase transition between a liquid and a solid. The researchers found that at a certain temperature called the onset temperature, the molecules in supercooled liquids become so viscous that they barely move, resulting in a transition from a liquid-like state to a solid-like state. This improved understanding could aid in the development of new amorphous materials for various applications.
The electroweak horizon is a problem that has been known for a long time, but which simply has not gotten the kind of attention that the cosmic microwave background radiation attracted. The electroweak field is symmetric when the cosmic temperature is high, and as the separate electromagnetic and weak fields take form, that symmetry is broken. However, no one has found any cosmic strings or any other evidence for the different regions of electroweak symmetry breaking, which is why it is included in the list of cosmology's crises.