{"id":33699,"date":"2025-07-24T12:33:11","date_gmt":"2025-07-24T12:33:11","guid":{"rendered":"https:\/\/www.newsbeep.com\/us\/33699\/"},"modified":"2025-07-24T12:33:11","modified_gmt":"2025-07-24T12:33:11","slug":"physicists-blast-gold-to-astonishing-temperatures-overturning-40-years-of-physics","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us\/33699\/","title":{"rendered":"Physicists Blast Gold to Astonishing Temperatures, Overturning 40 Years of Physics"},"content":{"rendered":"

Gold usually melts at 1,300 kelvins\u2014a temperature hotter than fresh lava from a volcano. But scientists recently shot a nanometers-thick sample of gold with a laser and heated it to an astonishing 19,000 kelvins (33,740 degrees Fahrenheit)\u2014all without melting the material<\/a>. The feat was completely unexpected and has overturned 40 years of accepted physics about the temperature limits of solid materials, the researchers report in a paper published in the journal Nature. \u201cThis was extremely surprising,\u201d says study team member Thomas White of the University of Nevada, Reno. \u201cWe were totally shocked when we saw how hot it actually got.\u201d<\/p>\n

The measured temperature is well beyond gold\u2019s proposed \u201centropy catastrophe\u201d limit, the point at which the entropy, or disorder, in the material<\/a> should force it to melt. Past that limit, theorists had predicted solid gold would have a higher entropy than liquid gold\u2014a clear violation of the laws of thermodynamics. By measuring such a blistering temperature in a solid in the new study, the researchers disproved the prediction. They realized that their solid gold was able to become so superheated<\/a> because it warmed incredibly quickly: their laser blasted the gold for just 45 femtoseconds, or 45 quadrillionths of a second\u2014a \u201cflash heating\u201d that was far too fast to allow the material time to expand and thus kept the entropy within the bounds of known physics.<\/p>\n

\u201cI would like to congratulate the authors on this interesting experiment,\u201d says Sheng-Nian Luo, a physicist at Southwest Jiaotong University in China, who has studied superheating in solids and was not involved in the new research. \u201cHowever, melting under such ultrafast, ultrasmall, ultracomplex conditions could be overinterpreted.\u201d The gold in the experiment was an ionized solid heated in a way that may have caused a high internal pressure, he says, so the results might not apply to normal solids under regular pressures. The researchers, however, doubt that ionization and pressure can account for their measurements. The extreme temperature of the gold \u201ccannot reasonably be explained by these effects alone,\u201d White says. \u201cThe scale of superheating observed suggests a genuinely new regime.\u201d<\/p>\n

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\"optics<\/a><\/p>\n

Project Scientist Chandra Curry works at the Linac Coherent Light Source at SLAC National Accelerator Laboratory.<\/p>\n

Jacqueline Ramseyer Orrell\/SLAC National Accelerator Laboratory<\/p>\n

To take the gold\u2019s temperature, the team used another laser\u2014in this case, the world\u2019s most powerful x-ray laser, which is three kilometers (1.9 miles) long. The machine, the Linac Coherent Light Source at the SLAC National Accelerator Laboratory in California, accelerates electrons to more than 99 percent the speed of light and then shoots them through undulating magnetic fields to create a very bright beam of one trillion (1012) x-ray photons.<\/p>\n

When this laser fired at the superheated sample, the x-ray photons scattered off atoms inside the material, allowing the researchers to measure the atoms\u2019 velocities to effectively take the gold\u2019s temperature.<\/p>\n

\u201cThe biggest lasting contribution is going to be that we now have a method to really accurately measure these temperatures,\u201d says study team member Bob Nagler, a staff scientist at SLAC. The researchers hope to use the technique on other types of \u201cwarm dense matter,\u201d such as materials meant to mimic the insides of stars and planets<\/a>. Until now, they\u2019ve had no good way to take the temperature of matter in such toasty states, which usually last just fractions of a second. After the gold trial, the team turned its laser thermometer on a piece of iron foil that had been heated with a laser shock wave to simulate conditions at the center of our planet. \u201cWith this method, we can determine what the melting temperature is,\u201d Nagler says. \u201cThese questions are super important if you want to model the Earth.\u201d<\/p>\n

The temperature technique should also be useful for predicting how materials used in fusion experiments will behave. The National Ignition Facility<\/a> at Lawrence Livermore National Laboratory, for example, shoots lasers at a small target to rapidly heat and compress it to ignite thermonuclear fusion. Physicists can now determine the melting point for different targets\u2014meaning the whole field could be heating up in the near future.<\/p>\n","protected":false},"excerpt":{"rendered":"Gold usually melts at 1,300 kelvins\u2014a temperature hotter than fresh lava from a volcano. But scientists recently shot…\n","protected":false},"author":2,"featured_media":33700,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[32],"tags":[79,28002,28005,28004,28003],"class_list":{"0":"post-33699","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-science","9":"tag-slac-national-accelerator-laboratory","10":"tag-solid-gold","11":"tag-temperature","12":"tag-thomas-white"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/33699","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/comments?post=33699"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/33699\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media\/33700"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media?parent=33699"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/categories?post=33699"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/tags?post=33699"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}