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Arthur T Knackerbracket has processed the following story:
Wafer-thin sheets of gold shot briefly with lasers can be heated up to 14 times their melting point while remaining solid, far beyond the theoretical limit, raising the possibility that some solids may have no upper melting point at all.
Superheating is a common phenomenon where a solid can heat up beyond its melting point, or a liquid can heat up past its boiling point, without changing state. For example, a cup of water heated in a microwave can reach temperatures above 100°C (212°F), as long as the cup is sufficiently smooth and still. However, as soon as the cup is jostled, the water will violently boil.
For solids, many physicists have proposed an upper limit for superheating, at a temperature around three times the standard melting point in kelvin. This point is called the entropy catastrophe, which is where the entropy, often defined as the amount of disorder in a system, for the solid state would become larger than if the substance were liquid. If the substance remained solid above this temperature, then it would violate the second law of thermodynamics, which says that entropy cannot decrease over time for most systems.
[...] It would also be interesting to see whether this applies to other solids apart from gold, says Vinko, and whether there is any upper limit to heating before melting. “The thing that’s intriguing here is to ask the question of whether or not it’s possible to beat virtually all of thermodynamics, just by being quick enough so that thermodynamics doesn’t really apply in the sense that you might think about it.”
Journal Reference: White, T.G., Griffin, T.D., Haden, D. et al. Superheating gold beyond the predicted entropy catastrophe threshold. Nature 643, 950–954 (2025). https://doi.org/10.1038/s41586-025-09253-y
DOI: 10.1038/s41586-025-09253-y
(Score: 2) by Tork on Wednesday July 30 2025, @05:19PM (1 child)
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(Score: 2) by sgleysti on Wednesday July 30 2025, @10:06PM
I don't think there are practical applications. From the summary, the chain of events goes like this:
1. We know some materials can be heated above their melting point without melting or heated above their boiling point without boiling in certain specific conditions.
2. Physicists proposed an absolute temperature limit of 3x the melting point for solids. Idea being if you get the solid that hot under any conditions, it'll melt.
3. The folks who wrote the paper got gold up to 14x the melting point without melting, but it was for a very short period of time—they used a 45 femtosecond laser pulse.
The folks in #3 were basically trying to see if they could exceed the limit of #2. Sounds like a "because we can" kind of scenario, but this should also help improve our understanding of how materials melt.