• @[email protected]
      link
      fedilink
      English
      1049 months ago

      Well, yes, as far as our theories go. But we also “knew” that light was a wave that traveled through the luminiferous aether, which permiated all of space… Until we tested that theory with the Michelson-Morely experiment, and it turned out our theories were completely wrong and physics as we knew it was completely upended.

      Point being, it’s important to actually test our theories instead of assuming they’re completely correct just because most of their predictions are accurate.

      • 1bluepixel
        link
        fedilink
        349 months ago

        Science advances by testing the limit cases. You do it and you do it until one day you get an unexpected result. That result, and the subsequent understanding of why it happens, is what leads to Nobel Prizes.

      • @[email protected]
        link
        fedilink
        49 months ago

        Aether was a fudge and pretty sure Einstein knew it. Forgot the exact history, but it was made up from whole cloth to make the math work out.

        • @[email protected]
          link
          fedilink
          English
          119 months ago

          Well yeah. The concensus at the time was that light is a wave, and waves need a medium to travel through, so they just made up some stuff that must be everywhere and called it the aether. The null result of the interferometer experiment is part of what led to the discovery that light is a particle that acts like a wave, and so doesn’t need a medium.

    • 1bluepixel
      link
      fedilink
      529 months ago

      I’m pretty sure every physicist in existence knows that. It’s just a simple principle that’s really hard to test, so actually testing it is pretty cool. Like dropping a steel ball and a feather on the Moon.

      • @[email protected]
        link
        fedilink
        -419 months ago

        Those are pretty expensive experiments. Are you sure they do them just because they are cool?

        • @[email protected]
          link
          fedilink
          English
          419 months ago

          We choose to go to the moon and to do the other things, not because they are easy, but because they make me hard

        • fiat_lux
          link
          fedilink
          14
          edit-2
          9 months ago

          It is possible to do something cool and something that furthers science at the same time. Deep down, doing cool stuff is probably why most research scientists exist. Because it isn’t for the mad stacks of cash, I can promise you that.

          Let the science people do their pew-pew-pew thing with the fancy toys and pretend they’re in Star Trek. At least they’re enjoying themselves while helping the rest of us out!

        • TheOneCurly
          link
          fedilink
          English
          69 months ago

          It’s also an excellent proof of concept for how to test with antimatter. Anyone who designs a test using anti hydrogen will look back at their methodology.

    • @[email protected]
      link
      fedilink
      3
      edit-2
      9 months ago

      It has a positive mass, and in every other way it acts just like normal matter going backwards in time (cpt inversion).

      If, despite its positive mass, it was pushed back by gravity, then it would have given even more weight to the theory that antimatter is just matter moving backwards.

      Since gravity is such a wonky interaction, I’m not even sure this result disproves the time-reversal theory entirely!

      • @[email protected]
        link
        fedilink
        139 months ago

        Why would inverting charge make particles go backwards in time? Electrons have opposite charge to protons and they don’t seem to. Positrons have the opposite charge to electrons and as far as I know they don’t go backwards?

        I think you’re misinterpreting cpt reversal symmetry, which is if you mirrored the universe in terms of charge, time and parity it would essentially evolve the same

  • ShadowRam
    link
    fedilink
    53
    edit-2
    9 months ago

    If an anti-gravity particle does exist (that expels both normal mass and itself), it would be incredibly hard to find.

    They would push away from each other and disperse outside of the solar system.
    Like 1 particle per 1000sq km kind of thing.

    Which would push all the galaxies away from each other, always accelerating away from each other, but in a decreasing fashion…

    It would also press inward on galaxies making it look like mass on the outer rims of galaxies having more gravity than they should.

    And there would be a SHIT ton of this matter, that would be dark because it’s so spread out,

    …wait a minute …

    • @[email protected]
      link
      fedilink
      English
      149 months ago

      Dark energy is not galaxies moving away from each other but instead its new space being created in between which makes it appear like they are moving away from each other. That’s why distant redshifts can exceed the speed of light, because they are not really moving, so the speed of light law is not broken.

    • @[email protected]
      link
      fedilink
      69 months ago

      Could it be a particle that has negative mass ?

      In this case it would not appear in the CERN.

      I’m way out of my field so please anyone, correct me if I’m wrong.

      The CERN is creating particles from pure energy, E=mc² means that if you focus a lot of energy in a single point some of the energy is turned into matter. From my understanding the generated matter is random particles.

      Now if we want to create a particle with negative mass we need negative energy. What is negative energy? I have no idea but if we manage to focus a huge amount of negative energy we will get particles with negative mass.

      • ShadowRam
        link
        fedilink
        39 months ago

        Do we need negative energy?

        Don’t particles appear out of thin are and then collide again and disappear?

        0 = E = -mc² + mc²

        You can have negative mass without requiring negative energy.

      • @[email protected]
        link
        fedilink
        -39 months ago

        If you created a negative mass particle at the same time as a positive mass particle, you’d essentially be able to do so with 0 or near 0 energy because they have opposite signs and would cancel out - negative energy plus positive energy. Free energy?

  • @PrincessLeiasCat
    link
    509 months ago

    I have a basic understanding of CERN, but if it comes down to it, everything they do there still blows my mind.

    Like, imagine being the person who designed that experiment.

    “Here is a CERN. Find out how antimatter falls.”

    And some one/team was like ok I got this. And then they showed up one day & did it.

    “Down. It goes down.”

    I know it was much more complex than that, but still…imagine having the brain that stores the information required to do this. It’s so fucking cool.

    • @[email protected]
      link
      fedilink
      379 months ago

      What you don’t see is the hundreds of people and countless hours of work that went into stuff like this. None of it is one person just showing up and making it happen. Everyone has their specific skill set and role in the project, no one knows everything. We see the result, but the day to day of this work would look mind numbingly boring to most people. It’s not about geniuses having inspiration strike and figuring out something amazing, it’s about months and years of staring at spreadsheets, analyzing data, fixing your mistakes, double checking, running the test again. It’s about not giving up not being wicked smart, though the people working on it are definitely smart. Also this is the expected result. We were sure it fell down not up already, this was a confirmation of that.

      • @slackassassin
        link
        159 months ago

        This is pretty accurate. I was part of a detector group that did a beam test at Cern this summer. Everyone there is super helpful and humble because they know it takes grit more than anything at the end of the day.

    • @[email protected]
      link
      fedilink
      89 months ago

      It amazes me that people have this much ability and brains to complete such things. Meanwhile look at me. sigh

      • @[email protected]
        link
        fedilink
        99 months ago

        It is many, many people working together. No one person has this much ability or brains, only by working together do we make big modern scientific discoveries.

  • @[email protected]
    link
    fedilink
    429 months ago

    Reading stuff like this is super funny when you have absolutely no idea how any of this stuff works.

    “Wow, antimatter falls down! Gravity sure do be like that!”

  • ColorcodedResistor
    link
    fedilink
    English
    25
    edit-2
    9 months ago

    My understanding of CERN comes explicitly from Neon Genesis Evangelion (1995) and Steins Gate (2011) …and possibly The Backrooms (2022)

    I do not have the gumption to mess with shadow companies jimmies.

    • @[email protected]
      link
      fedilink
      119 months ago

      Steins gate was introduction to CERN for me. And it scared the shit out of me. No, thank you. You do you.

    • beaubbe
      link
      fedilink
      8
      edit-2
      9 months ago

      I’ve heard hypothecies that antimatter was normal matter going back in time. But this disproves it since it would have been going in reverse in gravity.

      • @[email protected]
        link
        fedilink
        69 months ago

        I don’t think it works like that, it’s not as simple as doing the opposite of what we would normally expect the flow of time to dictate.

        • beaubbe
          link
          fedilink
          49 months ago

          Nope it doesn’t. But if it did it would have been neat!

      • @[email protected]
        link
        fedilink
        59 months ago

        Unless antimatter is also antigravity and the two cancel each other out, making it look normal to us.

      • @[email protected]
        link
        fedilink
        29 months ago

        In many instances it is very convenient to think of antimatter as normal matter going back in time. This is what makes Feynman diagrams so easy to use and powerful.

        Furthermore, CPT symmetry is a necessary condition for basically all scientific theories. This means that reversing time is literally identical to reversing ‘charge’ and ‘parity’ together - and in this context, reversing charge means swapping all matter for anti-matter and visa-versa. Reversing ‘parity’ roughly means swapping left and right across the whole universe.

        … Anyway, CPT doesn’t directly tell us that anti-matter particles are normal matter going back in time, but it does imply that that isn’t a bad way of thinking about it.

    • @[email protected]
      link
      fedilink
      79 months ago

      Correct, but negative matter might in theory work that way

      Either way, they still do these tests just to check that their theories remain consistent across a variety of edge cases

  • @[email protected]
    link
    fedilink
    189 months ago

    If you think this is cool, there is a [email protected] project for the LHC (worlds largest particle accelerator) run by CERN. You can donate your computer’s spare computational power and maybe find a new subatomic particle! I’ve been running it for years, very fun project to be involved in, no PhD required.

    • Mike
      link
      fedilink
      29 months ago

      A side note, with the announcement of the raspberry pi 5, there’s a lot of chatter about how the pi boards are big contributors to boinc.

  • @[email protected]
    link
    fedilink
    149 months ago

    So, they put all the antiatoms in a tin can, put it up high, then opened the top and the bottom of the can and saw which end they came out of. I love it.

  • ProletarianDictator [none/use name]
    link
    fedilink
    English
    119 months ago

    Unsurprising really. It seems fairly apparent that gravity merely influences the geometry of the substrate in which all known forms of matter & fundamental forces operate within. Something would have to seriously be fucky for antimatter to act counter to that geometry given it is comprised of similar particles with opposite charge. I’d assume astrophysicists know this, but wanted experimental proof for what seems to be straightforward logic from things we have experimentally confirmed.

    The real question is what form does this geometry use to exert influence on the matter operating within curved spacetime? How is that information carried and how does gravity interface with that?

    • @[email protected]
      link
      fedilink
      49 months ago

      Antimatter is not just matter with an opposite charge. It’s matter with every type of charges (electromagnetic, strong and weak nuclear charges) inverted, as well as the “parity”, that is the relative direction of its spin compared to its propagation direction, are all inverted.

      If you look for “CPT symmetry”, you’ll find better explanations than this.

      It basically boils down to this: invert the flow of time, and every particle will look like antimatter, while antimatter will look like normal matter.

      It would have been very likely that antimatter moved backwards in gravity of it was normal matter moving backwards in time!

        • fox [comrade/them]
          link
          fedilink
          English
          49 months ago

          There’s also no real reason for there to be more matter than antimatter in the universe. Any sufficiently high energy action will produce equal amounts of matter and antimatter, but there’s overwhelmingly more matter than antimatter floating around. It’s one of the big questions.

      • TankieTanuki [he/him]
        link
        fedilink
        English
        39 months ago

        invert the flow of time, and every particle will look like antimatter,

        You just wrinkled my brain.

    • @[email protected]
      link
      fedilink
      29 months ago

      No offense, but nothing you wrote here makes any sense. You’re right (if I’m ‘translating’ this correctly), but you’re mix-and-matching various concepts here.

    • rubpoll [she/her]
      link
      fedilink
      English
      69 months ago

      In my next life I want to live my life backwards. You start out dead and get that out of the way. Then you wake up in an old people’s home feeling better every day. You get kicked out for being too healthy, go collect your pension, and then when you start work, you get a gold watch and a party on your first day. You work for 40 years until you’re young enough to enjoy your retirement. You party, drink alcohol, and are generally promiscuous, then you are ready for high school. You then go to primary school, you become a kid, you play. You have no responsibilities, you become a baby until you are born. And then you spend your last 9 months floating in luxurious spa-like conditions with central heating and room service on tap, larger quarters every day and then Voila! You finish off as an orgasm!