Comment on We've got it all worked out

Zerush@lemmy.ml ⁨1⁩ ⁨month⁩ ago

• neon_nova@lemmy.dbzer0.com ⁨1⁩ ⁨month⁩ ago

  I don’t think this is true. Just a myth or it only occurs in certain circumstances.

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  • Zerush@lemmy.ml ⁨1⁩ ⁨month⁩ ago

    Not a myth, it’s known as Mpemba effect, several hypothese about it, but still not clear

    en.wikipedia.org/wiki/Mpemba_effect

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    • neon_nova@lemmy.dbzer0.com ⁨1⁩ ⁨month⁩ ago

      In 2016, Burridge and Linden studied a slightly different measure, the time it took water samples to reach 0 °C but not freeze. They carried out their own experiments, and reviewed previous work by others. Their review noted that the large effects observed in early experiments had not been replicated in other studies of cooling to the freezing point, and that studies showing small effects could be influenced by variations in the positioning of thermometers: “We conclude, somewhat sadly, that there is no evidence to support meaningful observations of the Mpemba effect.”

      From the Wikipedia article.

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      • jwmgregory@lemmy.dbzer0.com ⁨1⁩ ⁨month⁩ ago

        i mean, you’re really burying the lead there when the article states pretty clearly in the abstract that the existence of this is contentious.

        your quote doesn’t really demonstrate it doesn’t exist, it just demonstrates what the article already clearly states which is that people don’t agree.

        it’s disingenuous to quote that specifically while ignoring things like:

        In 2021, John Bechhoefer described a way to reliably reproduce the effect.[23] In 2024, Argelia Ortega, et al. studied the freezing of small (1-20mL) drops in a Peltier cell with a thermographic camera, and found that hot drops consistently froze faster than cold ones, with a more pronounced difference for larger drops. In particular, hot drops finished freezing sooner after the onset of recalescence, and experienced less of a temperature spike during the freezing process.[24]

        from the exact same article, is all i am saying. bad rhetoric.

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      • Xavienth@lemmygrad.ml ⁨1⁩ ⁨month⁩ ago

        Modern studies using freezers with well-understood properties have observed the Mpemba effect where water supercools before freezing. Water that starts out cooler tends to reach a lower supercooled temperature before freezing.

        Also from the Wikipedia article.

        If you define the Mpemba effect as hot water reaching 0 degrees faster, then no, it’s not observable. But if you define the Mpemba effect as heated water freezing sooner, (remembering that freezing can initiate below the “freezing point” when water is subcooled) then the Mpemba effect may be observed.

        If true, it would be interesting that cool water is less likely to nucleate and form ice than water that was heated.

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