• @fujiwood@lemmy.world
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    10 months ago

    Everyone always asks what is gravity.

    No one ever asks how is gravity.

    Poor gravity, always helping us keep our shit together but no one ever truly understands the weight on gravities shoulder.

    • @e033x@lemm.ee
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      3910 months ago

      Excuse me, but I don’t see why I should have sympathy with the boot on our necks keeping us all down. Just imagine the freedom we would have if we weren’t weight down by this oppression!

  • Turducken
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    8210 months ago

    Perfect use of this format. “I don’t know” is the foundation of wisdom. See: reddit where too many think they know.

  • @bstix
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    6210 months ago

    It’s not difficult. Gravity is like magnetism for things that aren’t magnetic.

      • @bstix
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        1110 months ago

        I will assume that to be true, because it makes sense.

          • @charliespider@lemmy.world
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            1510 months ago

            Photons have no rest (invariant) mass, and gravity doesn’t directly affect photons, but does warp the spacetime that the photons travel through. That said, photons do possess energy which can also affect things gravitationally, even other photons.

              • @charliespider@lemmy.world
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                210 months ago

                Well you can say that about anything can’t you?

                wE dOnT kNoW wHaT rEd iS!

                We can name thousands of variations of the color red, we can measure the wavelength of the light that produces the color red, we can build machines and devices that manipulate matter at the quantum level to produce the color red, and yet… it’s still impossible to actually say what red is, and no one knows if what they perceive as red is the same as what others perceive.

                So ya we don’t “know” the ultimate true nature of gravity, and yet…

                …even babies and simple animals learn and understand that gravity exists, and we can measure gravity to astonishing levels of accuracy, and we understand gravity enough that we can launch a rocket up into space that then launches a probe that can travel millions of kilometers through space over several years and land on the surface of a comet that’s travelling tens of thousands of kilometers an hour, but ya… “we don’t know what gravity is”

                If you can spend your entire life studying the mountains of data and literature that we have amassed about a topic, then is it honest to say we know nothing about that topic?

          • @bstix
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            510 months ago

            Yeah… about that… I have nothing clever to say.

            Our laws of physics aren’t really suited for it, and everything seems so round-about that it looks like that time when people tried to argue for having Earth be the centre of the solar system. It’s all just patches to something that we know isn’t that simple.

          • @Knusper@feddit.de
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            210 months ago

            This isn’t the first time, I’m hearing about light being affected by gravity, but like, are we saying that electric fields and magnetic fields are not affected by gravity… except they are, when they oscillate back and forth in the form of an electromagnetic wave?

            • Blóðbók
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              110 months ago

              My understanding of EM fields compels me to say that they are affected by gravity because the mediating particles are.

              • @Knusper@feddit.de
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                110 months ago

                I’m guessing by “mediating particles”, you don’t mean those affected by fields, but rather those ‘propagating’ the field, i.e. photons.

                And well, my research tells me that photons don’t really exist. 🙃

                Well, particles don’t really exist, in the traditional sense. They’re not solid balls flying through space. They’re rather just peaks in the EM and gravitational fields. And then, if you’ve got a disturbance in a field, a peak or wave will travel along the field, which propagates that disturbance. And if you’ve got all that internalized, then you could call that peak/wave a “particle” again.

                Here’s a rough source / different explanation of those claims: https://physics.stackexchange.com/a/201

                But yeah, I don’t think this particle analogy is helping us here. We’re ultimately still just talking about a field being affected by gravity.

                (Still, thanks for the input. I’m sorting my thoughts as I go, and reading that I’ve also been subjected to an unhelpful analogy is helping it make sense.)

                • Blóðbók
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                  110 months ago

                  I also like to say that particles don’t really exist in any sense one would associate to the word. And to be pedantic, we can’t even say that particles are peaks in a field because that is merely how we model it, and that model is incomplete.

                  Since we don’t know what gravity is or does, nor what (or if) a field is or what particles are, it’s hard to answer a question like whether a particular field is affected by gravity other than in terms of a specific model and hope that corresponds to real observations.

                  In this case, our best bet is to reason in terms of known properties of what we think of as particles mediating the field in question. Photons are subject to gravitational influence, and so we expect EM fields to be as well.

    • @thedarkfly@feddit.nl
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      110 months ago

      Yeah but if you scratch a little bit the surface, the comparison falls quickly. Okay, magnetism has two signs. Why not gravity ? Why does it attract and not repel? Okay, magnetism is carried by photons. What carries gravity?

    • @Aurenkin@sh.itjust.works
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      4110 months ago

      No silly, gravity is caused by the fundamental fear of loneliness so pervasive and unrelenting in the universe that it causes the formation of stars and planets.

      • @novibe@lemmy.ml
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        10 months ago

        This is no joke, pretty much most mystical religion’s cosmology.

        Like Kabbalah, Advaita Vedanta, Sufism etc.

        Not the gravity part, but basically that the first thought, after being came into existence, was longing for another, to be united.

        The first existence is in itself a separation from chaos, so its nature is “will”, wanting to fill a void.

  • @SuddenDownpour@sh.itjust.works
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    4210 months ago

    “The nature of this elementary particle is best expressed through these thirty equations.”

    “Ok, ok, but what do those actually mean in reality?”

    “Reality?”

      • @Uncle_Bagel@midwest.social
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        2410 months ago

        American salaries are also always presented as gross income before taxes instead if net income after taxes like in Europe.

        • tryptaminev 🇵🇸 🇺🇦 🇪🇺
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          1810 months ago

          we also do gross before taxes in Germany. 57k before taxes is still a solid salary in many areas of Germany. Some MINT and Financelords might want to disagree with that, but it is in the top 15% of salaries. At that Level you pay about 5,1k taxes, 5,3k pension and 4,6k for health, 1,3k eldercare and 750 unemployment insurance. (all mandatory)

          That seems quite a lot at first, but for instance unemployment pays 60% of your net income up to a year qfter loosing a job, health insurance also covers all children until they are 25 or earn more than 500€/month.

          • @Asafum@feddit.nl
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            10 months ago

            It only sounds like a lot of taxes to us Americans that don’t actually do the math… I’m making almost 60kUSD so it’s a very real comparison for me. Like your 4.6k healthcare tax is my 14.4k pay cut (mandatory healthcare coverage for full time employees paid for by the owner @1,200/month for me) Your 5k general tax is higher than my 3.6k income tax, but everything else offsets that by such a large margin that arguing against it is laughable.

            Thing is we also pay a ton of of pocket when we go to the doctor too.

            I wish we had a number to use like your 4.6k but for America so in our arguments for universal healthcare we could show just how much more we really pay…

            Sorry for all the edits, I remember as I reread lol

              • @Asafum@feddit.nl
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                610 months ago

                A not insignificant amount of money goes towards administrative pay for all the middlemen involved…

                Everyone has to get their slice of the… (Checks notes) necessary medical treatment of human beings… Ughh…

          • @Damage@feddit.it
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            10 months ago

            57k gross is a bangin’ income in Italy, at that level you pay about 35-40% in taxes if you have no deductibles etc, which means net 2631€/month, about twice the average.

            You could work alone and support a stay-at-home wife

        • @BigNote@lemm.ee
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          110 months ago

          Really? I had no idea. It turns out I make a lot more money than I thought.

    • @AlexWIWA@lemmy.ml
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      1210 months ago

      You can basically half American salary numbers because we have to pay for a lot of stuff that Europeans usually don’t need to pay for. $57k in America is struggling if you live in a city. Anything below $40k is one car repair away from being financially ruined.

      • @DudePluto@lemm.ee
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        10 months ago

        What are we considering in vs out of city? Does in city mean just downtown, within city limits, within metro area? And what are we considering a city - 300k population?

    • @I_Has_A_Hat@lemmy.ml
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      210 months ago

      The biggest lesson from neuroscience: Most psychology is BS and the entire field is little better than pseudoscience.

    • @daellat@lemmy.world
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      510 months ago

      https://www.youtube.com/watch?v=XRr1kaXKBsU try to follow along with this. Also, forces have force particles, there appears to be no such thing for gravity though I think scientists are still working on this problem to this day. Mass seems to be derived from the higgs field but I am not knowledgeable enough to answer how that relates to gravity per se.

        • @paholg@lemm.ee
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          110 months ago

          Are you sure about that? My understanding is that gravitational waves are predicted by general relativity, not inconsistent with it.

          In any case, “all models are wrong, but some are useful”. Gravity as curvature is a pretty damn useful model.

          • @merc@sh.itjust.works
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            110 months ago

            No, I’m not sure about it. And general relativity did predict gravity waves, and did generally describe gravity as being the curvature of spacetime.

            Having said that, if “gravity waves” move at the speed of light, but speed is distance over time, how can you measure a “speed” when the thing whose speed you’re measuring warps the units you use to measure it? It seems like you could talk about the movement of gravitational waves from the point of view of an observer outside the system with a ruler and a stopwatch that were unaffected by gravity. But, general relativity seems to suggest that there are no absolute / external reference frames you could use.

            I fully admit that I don’t completely get general relativity, and that it has been a very useful model. It just seems like it can be a useful model even if there are certain dusty corners where you shouldn’t spend too much time looking because things stop making sense there.

  • Dr. Coomer
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    3010 months ago

    Genuinely we can’t tell what it is. We once thought it was just a normal pull due to mass until Einstein proved us wrong during a solar eclipse where we could see stars that shouldn’t be visible from our current position in orbit. Then we get into how it works, WHICH THERE IS NO TELLING AS THERE ARE TO MANY GOD DAMNED VARIABLES INVOLVED.

      • @neryam@lemmy.world
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        2510 months ago

        Stars that were behind the sun (within the radius of the sun, geometrically speaking) were visible due to gravitational lensing

          • @Classy@sh.itjust.works
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            810 months ago

            It isn’t directly analogous because one is gravitational and the other is not, but if you’ve ever watched a ship sail beyond the horizon, sometimes you can see a reflection of the sail after it is no longer in direct sight, because the way that light can reflect around the curvature of the earth. It’s a pretty crazy phenomenon.

            https://en.m.wikipedia.org/wiki/Mirage#Superior_mirage

            In the case of the OP, as light from distant stars approach the sun, some of their light that may normally have passed to the side of the sun and beyond the earth, thus rendering them invisible, are instead ‘bent’ back towards the earth by the sun’s gravitational well. But since the sun is so luminous we normally cannot see those stars. If the sun were somehow dark we would see a collection of tiny, distorted stars around the perimeter of it.

            To metaphorize: imagine a ball rolling straight from a point directly in front of you, but at an angle such that it won’t roll to you. Now imagine a dip in the ground, not deep enough to cause it to fall in and not escape, but enough to cause the ball to curve as it rolls, sending it to you instead. The sun acts in a similar manner on light.

            • @deadbeef79000@lemmy.nz
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              10 months ago

              An analogy I’ve used with my children.

              Sit in the middle of our trampoline. Roll a ball in a straight line beside you. Watch it roll around you and fall into the depression you make in the trampoline surface.

              This is a primitive 2 dimensional simulation of gravity.

              The ball “thinks” the surface is a flat plane, as far it knows it’s rolling in a straight line.

              You are the heavy object curving space(time). Your eyes are a higher (3rd) dimensional observer and can see the curvature and it’s effect on the ball.

              If you roll them ball fast enough, it curves slightly and then escapes your “gravity well”. It has changed course slightly. This the gravitational lensing simulation.

          • @Krauerking@lemy.lol
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            710 months ago

            Yeah it sounds silly but like it’s a weird thing to see stars that are literally behind another object because it weighs enough and it’s a interesting story for Einstein who has a moment discovering it.

          • @AssholeDestroyer@lemmy.ml
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            310 months ago

            The James Web Space Telescope’s Instagram page posted the phenomenon recently. Gravity from nearby galaxies magnifies space near them, allowing the telescope to see incredibly far away galaxies.

          • @FarceMultiplier@lemmy.ca
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            210 months ago

            If you really want to be messed up, absolutely nothing is where we think it is because gravitational lensing affects the light of every object in the universe, while we observe. The further away it is, the more light is warped by the masses along the path, and we can’t know what those many masses are or where they are either.

            Our observability of the universe is a guessing game as large as the universe, and there is no conceivable model to assess it all and the interrelations between…everything.

            • @theangryseal@lemmy.world
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              110 months ago

              Now this is something that I knew absolutely nothing about, but I feel like it should have occurred to me with what I did know.

              Thank you.

  • wjrii
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    10 months ago

    The squishy humanities version of this, in America at least, goes as follows:

    In grade school you learn that the Civil War was about slavery.

    In high school you learn that the Civil War was about a lot of complicated things.

    In college you learn that the Civil War was about slavery.

      • wjrii
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        1610 months ago

        My mom (RIP) was a boomer born and raised in Georgia. In our house, we were taught that General Sherman was in hell right alongside Napoleon and Hitler.

        If he is, it’s for his handling of the Native Americans and bison and not for how he prosecuted the March to the Sea. The Confederacy was a boil that needed popping.

        • @DragonTypeWyvern@literature.cafe
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          310 months ago

          My general thought on the March is that glorifying a series of war crimes and mass civilian death is never a good thing, and it wasn’t the wannabe aristocratic slave owners that suffered the most from it.

          But war is hell, which is why you should always try to avoid starting one, especially for a contemptible cause.

          The March should be filed under the same general heading as the WW2 bombing campaign, it’s one thing to view it as a necessary evil but it’s another thing to revel in it.

    • Turducken
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      210 months ago

      Apu learned in post-grad glasses that it was complicated again.

      • wjrii
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        210 months ago

        That gag is cute, and I’m aware I’m killing the joke here, but it would have been funnier if it weren’t for the fact that underpinning the “economic factors, both foreign and domestic” was just more slavery. The South was utterly dependent on it for their economic security and social identity, and it informed every decision their leaders made.

        • Turducken
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          110 months ago

          Nah, Apu’s PhD is in comp sci. The joke is his extensive education. It sucks that so many very talented and educated folks have to start a business to legally stay in the US.

    • @Shard@lemmy.world
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      1010 months ago

      Now you can too! With our patented PhD system you will,

      1. Kill your social life!
      2. Kill your self-esteem, values, positivity and much much more.
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      With just 132 simple payments of $3,800 a month, all this can be yours!

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      • @NotSpez@lemm.ee
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        310 months ago

        Oh and then!? Postdocs! Check acollierastro on youtube, she has a great video on postdoc exodus.