Superheated Gold Defies ‘Entropy Catastrophe’ Limit, Overturning 40-Year-Old Physics
Physicists recently achieved a groundbreaking feat by superheating gold to 14 times its melting point without causing the material to melt. This unexpected discovery has overturned 40 years of accepted physics about the temperature limits of solid materials. The research, published in the journal Nature, showcases the remarkable capabilities of modern technology in pushing the boundaries of scientific knowledge.
Gold typically melts at 1,300 kelvins, a temperature hotter than fresh lava from a volcano. However, researchers managed to heat a nanometers-thick sample of gold to an astonishing 19,000 kelvins (33,740 degrees Fahrenheit) using a powerful laser. This extreme temperature far surpasses the proposed “entropy catastrophe” limit for gold, a point at which the material should theoretically melt due to increased disorder. The experiment demonstrated that solid gold can withstand such high temperatures, challenging existing theories in thermodynamics.
The key to this unprecedented achievement lies in the rapid heating process employed by the researchers. By subjecting the gold sample to a laser pulse lasting just 45 femtoseconds (45 quadrillionths of a second), they initiated a phenomenon known as “flash heating.” This rapid heating prevented the material from expanding and exceeding its entropy limits, allowing it to remain in a solid state at temperatures well beyond what was previously thought possible.
While some experts caution that the experimental conditions may not accurately reflect the behavior of normal solids under regular pressures, the researchers stand by their findings. They argue that the extreme temperature reached in the experiment cannot be solely attributed to ionization and pressure effects. The results suggest a new regime of superheating that challenges conventional understanding of solid materials.
To measure the temperature of the superheated gold, the team utilized the Linac Coherent Light Source at the SLAC National Accelerator Laboratory in California. This state-of-the-art x-ray laser provided unprecedented insights into the atomic velocities within the material, allowing for accurate temperature measurements. The researchers believe that this technique could revolutionize the study of “warm dense matter,” offering new ways to explore conditions resembling those inside stars and planets.
In addition to its implications for fundamental physics, this research has practical applications in fields such as fusion experiments. By accurately determining melting points for different materials, scientists can better predict and control the behavior of materials under extreme conditions. This breakthrough opens up new possibilities for advancing our understanding of complex systems and phenomena, paving the way for future discoveries in science and technology.