Gold stubbornly remains solid: subjected to temperatures 14 times hotter than its melting point and remains unmelted
In a groundbreaking experiment, a team of physicists from the SLAC National Laboratory in California, USA, have heated a gold foil to a staggering 19,000 Kelvin—about 14 times its normal melting point—without it melting [1]. This discovery challenges fundamental assumptions about matter's behavior at extreme temperatures, with far-reaching implications for physics, fusion, astrophysics, and material science.
The experiment was carried out using ultra-rapid X-ray technology, specifically the Linac Coherent Light Source, the world's first free-electron laser for X-rays [7]. The key to maintaining the solid state of the gold was the extreme speed of heating, achieved through a laser pulse of just 50 quadrillionths of a second [4].
Thomas White and Bob Nagler led the SLAC team that conducted the experiment. The MEC (Matter in Extreme Conditions) instrument at SLAC was used in the experiment, along with a unique combination of laser and X-rays [8]. The gold remained intact not due to inherent resistance, but because it didn't have time to break [9].
This finding challenges the "entropy catastrophe," a physical theory about the thermal stability of materials. Rapid heating on such a scale prevents atomic rearrangement and expansion needed for melting, allowing gold to remain solid far above its melting point without violating thermodynamics [3].
The discovery opens up a new field of study, as it suggests that solid materials can exist metastably at temperatures previously thought impossible [2]. This provides new insight into non-equilibrium physics and the dynamic behavior of matter when heated faster than it can structurally respond [3].
Understanding such ultra-rapid heating and solid-state persistence informs controlled fusion research and plasma modeling. If metals or plasmas can be stabilized transiently at extreme temperatures, it may lead to innovative approaches to fusion diagnostics, energy confinement, or new material phases applicable in reactors [1][2].
The experiment also has implications for astrophysical models. Since these temperatures exceed the sun's surface temperature, the experiment may shift how scientists model matter in stellar atmospheres or planetary cores, where transient superheating and rapid fluctuations occur [2][4].
Moreover, this opens the possibility to engineer materials with unprecedented thermal resilience and properties by exploiting ultrafast heating techniques. This fundamentally expands the temperature regimes for solid-state applications and novel phases beyond equilibrium thermodynamics [2][5].
In summary, by defying conventional melting limits through ultrafast laser heating, this work pushes the boundaries of thermal physics, energy states, and material stability. The ripple effects of this discovery are expected to be felt across fusion energy, astrophysics, and advanced materials science [1][2][3]. Further research is required to explore how widespread this phenomenon is and how it might be harnessed in practical technologies.
The SLAC National Accelerator Laboratory, affiliated with Stanford University, is one of the most advanced institutions in the world for studying matter under extreme conditions. It is currently developing research in solid-state physics, extreme chemistry, and experimental astrophysics, with facilities like the LCLS-II, FACET-II, and NLCTA for advanced research [6].
References:
- Gold Heated to 19,000 Kelvin Without Melting
- Ultrafast Laser Heating of Gold Foil to 19,000 Kelvin Without Melting
- Ultrafast Laser Heating of Gold Foil to 19,000 Kelvin Without Melting: A New Paradigm in Physics
- SLAC's Linac Coherent Light Source
- SLAC National Accelerator Laboratory
- SLAC Research Areas
- Linac Coherent Light Source
- Matter in Extreme Conditions
- Gold Remains Intact Due to Extreme Speed of Heating
- The recent breakthrough in heating gold to 19,000 Kelvin without it melting was achieved through the application of science and technology, namely ultra-rapid X-ray technology and the Linac Coherent Light Source.
- This new paradigm in physics, which challenges the "entropy catastrophe" and showcases the solid-state persistence of gold at temperatures previously thought impossible, has significant implications for fields such as fusion research, astrophysics, and materials science.
