{
  "id": 3568194,
  "title": "Liquid gallium experiment confirms key flow regime inside rapidly rotating stars and planets",
  "url": "https://urgent.news/2026/08/26/liquid-gallium-experiment-confirms-key-flow-regime-inside-rapidly",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-26T18:40:05.000Z",
  "source": {
    "name": "Phys.org",
    "slug": "phys-org",
    "url": "https://phys.org/news/2026-08-liquid-gallium-key-regime-rapidly.html"
  },
  "original_language": "en",
  "account": "A groundbreaking experiment conducted by an international team of researchers, led by UCLA, has confirmed a critical flow regime within rapidly rotating stars and planets. Lab experiments are crucial in replicating the physical processes that occur inside these celestial bodies, as direct observation is not possible. The Helmholtz-Zentrum Dresden-Rossendorf (HZDR) also contributed to the study, which was published in Physical Review Letters. The research provides a solid experimental basis for testing theoretical models of the processes happening inside stars and planets.\n\nConvection plays a vital role in transporting heat within stars and planets, with hot material rising and cooler material sinking. This process creates turbulent flows that generate Earth's magnetic field and shape the dynamics of stars. When these flows are found inside rapidly rotating celestial bodies, they reach a unique state known as the diffusivity-free regime. In this state, large flows are almost entirely influenced by buoyancy and rotation, while fluid properties like viscosity or thermal conductivity become negligible. However, previous studies had struggled to confirm this regime experimentally due to the formation of thermal boundary layers on the walls of test vessels, which affected the flow and obscured its true state.\n\nTo overcome this challenge, the research team employed a rotating liquid-metal experiment using liquid gallium as the test medium. They utilized a special oscillating flow mode exclusive to liquid metals, which is not determined by thermal boundary layers on the vessel walls but rather by the temperature gradient inside the liquid. This allowed the team to create the conditions predicted by models for the diffusivity-free regime. Dr. Jewel Abbate, who conducted the research as part of her Ph.D. studies, stated that the experiment successfully demonstrated this theoretically predicted state in the lab for the first time. This breakthrough significantly strengthens confidence in the models used to describe processes inside stars and planets.\n\nTo validate their experimental results, the researchers compared three independent metrics—the heat transport, flow velocity, and temperature fluctuations within the fluid—against theoretical predictions. All three metrics matched the models quantitatively. Additionally, high-resolution numerical simulations further confirmed the results. The agreement between theory, experiment, and numerical simulations is particularly compelling, as it allows for the experimental confirmation that the underlying physical models describe heat transport very accurately. This discovery fills a longstanding gap between theory and experiment, providing more reliable models for investigating the dynamics inside stars and planets in lab experiments—leading to a better understanding of fundamental processes in the universe.",
  "summary": "Since we cannot look into the interiors of stars and planets, we rely on lab experiments to replicate the physical processes that occur there. Led by the University of California, Los Angeles (UCLA), an international research team has produced the first experimental verification of a theoretically predicted flow state deemed characteristic of the interiors of rapidly rotating celestial bodies.…",
  "key_points": [
    "UCLA-led international team confirms diffusivity-free regime in rapidly rotating stars and planets",
    "Liquid gallium used as test medium in rotating liquid-metal experiment",
    "Experimental results align with theoretical models and numerical simulations"
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}