• Madlaine
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    201 year ago

    Uh, I’m surprised.

    I learned this in school more than a decade ago.

    Did my teacher accidentally lied the truth?

    • @rdyoung
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      211 year ago

      Light is energy. This isn’t surprising to me at all.

      • @[email protected]
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        301 year ago

        The energy transfer to evaporate water is the heat. This is specifically without heat.

        They proved more water was evaporated than the heat applied to the water.

        The theory being the light knocks away water particles at the surface of the water without heating them.

        • @bouh
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          111 year ago

          So, in fact, water will evaporate without heat because of the lack of equilibrium between air and water, until the air is wet enough for the process to stop.

          Discovering that light vaporise water is not the same as discovering that water vaporise itself without heat. It is an interesting discovery nonetheless.

          • @[email protected]
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            71 year ago

            Up to 3 times more water evaporated than heat energy the light could supply.

            It’s pretty massive if true.

        • @rdyoung
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          -121 year ago

          That’s literally not possible. It may be heat that we don’t have sensitive enough equipment to detect but light is energy and it hitting the water will release heat.

            • @rdyoung
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              1 year ago

              I don’t think you have the grasp on things that you think you do. I’m not in the mood nor do I have the time to have a beginners class on this so I suggest you do some reading on your own and learn how to analyze things and come to your own conclusions. Way way too many studies are straight up faked at worst, at best they are tweaked and results that say something different are thrown out or ignored.

              By this logic, when we heat up food or drinks in the microwave we are not using heat at all. We are in fact generating heat as the water molecules are excited by the energy in the radio waves being transmitted towards whatever is in the microwave. For those who may not know, radio waves are just light we can’t see because our eyes don’t have whats needed to see them.

              You know what. Ignore everything I said above and keep on keeping on. Stay ignorant and full of yourself. See how far that gets you in life.

              • @Jtotheb
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                121 year ago

                I hope you lack the time because you’re setting up your own study. This one was set up due to previous observations of rates of evaporation double or greater than those understood to be mathematically possible. Hell of an equipment error. It also observes a difference in the rate of evaporation under different colors of light, with the highest rate of evaporation occurring under green light, which you would probably also deem impossible, since color has nothing to do with it and green isn’t even the most energetic wavelength. An MIT professor, a postdoc, and four others hang their hat on these results, and the reality of this phenomenon. rdyoung disagrees with them in a comments section on an obscure forum. Which source might be more credible?

                • @rdyoung
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                  -181 year ago

                  You also definitely don’t understand what I or the study is saying. Not surprised here at all.

                  Again, as I said. Maybe we don’t have the tech to read the miniscule amount of heat in a photon of light or the heat generated as the light excites the water molecules, that doesn’t mean that heat wasn’t a part of it.

                  Yet another one who has no idea or grasp of the concepts at play here.

                  Just like reddit, I thought a sub such as this would have a smarter community but once again you lot proved me wrong and showed me that no matter how dumb I think people can be, they can always surprise you with the idiocy.

                  I’ll leave you with a quote from Harvey Danger.

                  Been around the world and found That only stupid people are breeding.

              • @surewhynotlem
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                41 year ago

                First, being rude makes you look like you don’t know what you’re talking about. Condescension in technology and science is very ‘last century’.

                Second, you’re right. This article is a bad translation at best. If the light interacted with the water in any way that produced motion and caused evaporation, that motion IS heat.

                They probably mean to say that they can evaporate water directly with light without having to use a heating element or something non-water to absorb the light. That’s my best guess at translating a poorly written article at least.

                • @Jtotheb
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                  1 year ago

                  From the abstract: “We interpret these observations by introducing the hypothesis that photons in the visible spectrum can cleave water clusters off surfaces due to large electrical field gradients and quadrupole force on molecular clusters.”

                  The commenter’s interpretation of the summary was pretty close to the language Chen used.

                  To be clear, this article is written by an English native speaker who is summarizing a study written in English primarily by a man who’s been at U.S. universities for three decades. Unless you meant it was a bad summary, which I don’t think it was, but that’s opinion.

                • @[email protected]
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                  11 year ago

                  No they literally state more water was evaporated than heat energy from the light could do by up to 3 times.

                • @rdyoung
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                  1 year ago

                  Oh look, another snowflake who reads factual statements as being rude. Fuck off with that shit.

                  The above said, thank you for being one of the few who actually gets it. There is heat everywhere there is light even if we can’t detect it with equipment. The light exciting the water molecules generates heat, this is a fact that could only be argued with by those who think birds aren’t real and/or that JFK will rise from the dead and bring along Lincoln as his vp.

                • @rdyoung
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                  1 year ago

                  What exactly are you talking about? What in any of my comments here lead you to that assumption? Or were you so horned up to make that comment that you responded to the wrong person?

                  As for my marriage. Happier than you could ever hope to be and having more sex in a week than you probably have in a decade all while working a reasonable number of hours and taking time off whenever I feel like it (I am self employed). Also buying a house and 3+ acres. Take a ton of vacations, see ever concert we can fit in to our schedule and even some we shouldn’t. For example, just saw Theory Of a Deadman, Saint Asonia and Skillet in Salem VA. Have Creed next summer, Hagar, Vai, etc next spring iirc among others.

                  If you had any working braincells you would cross reference my username here on other platforms. That would give you an idea of who I am, what I am and what the fuck is really going on here.

                  I don’t actually want your answer here so I will be proactively blocking you.

              • El Barto
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                01 year ago

                Haha, what a nice trolling attempt!

      • @PeachMan
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        91 year ago

        Yeah that’s the part that confuses me…how does one transfer energy to something without generating any heat?

        • JanoRis
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          201 year ago

          They explain that in the article. Light barely gets absorbed in water, which is why you can see several meters deep in water. Only the absorbed part can turn into heat.

          They measured an effect that partly evaporates water more efficiently than the heat influx can. The theory mentioned in the article is, that light directly knocks out water molecules at the water/air surface boundary. The measured effect was the most effective with light of a green wavelength

        • TheOneCurly
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          41 year ago

          Heat doesn’t really exist at an individual particle level, it only describes the average kinetic energy of a large number of particles. “Normal” evaporation occurs because all the water molecules are jiggling around fast enough that sometimes some get knocked off at the top and fly away. The theory from this paper says that light can strike a single water molecule just right that it breaks off without help from the others.

          Saying this is “without heat” means that the light isn’t simply increasing the average kinetic energy at the top of the water and speeding up the rate of “normal” evaporation. They think it’s specifically acting on a single molecule at a time.

  • @Jtotheb
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    121 year ago

    Okay, this study has absolutely fascinated me. Tried to find the full study but failed, but Gang Chen (MIT professor, primary author) has a 40 minute symposium about it. Piped bot incoming, hopefully: https://m.youtube.com/watch?v=B1PbNTYU0GQ

    • m3t00🌎OPM
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      61 year ago

      I like pounding YouTube on firefox with full ad-blocks engaged. hehe funny how nobody noticed. light is a range of frequencies so I’d expect best results at some harmonic frequencies.

    • @steeznson
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      61 year ago

      Potentially the bot will struggle with a mobile link but depends on the regexes it is using. I’d be surprised if it didn’t find it though!

  • @Fedizen
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    51 year ago

    is this analogous to the photoelectric effect?

    • m3t00🌎OPM
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      31 year ago

      photoelectric effect?

      looks similar. pe frees electrons while this experiment frees h2o molecules. they didn’t really speculate on the exact mechanism. only something to do with the gel medium