• petrol_sniff_king@lemmy.blahaj.zone
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    3 days ago

    In Einstein’s general relativity, different observers can disagree about the order of timed events, so long as their individual stories don’t violate causality. This is broadly known as the Relativity of Simultaneity.

    • Lvxferre [he/him]@mander.xyz
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      3 days ago

      [Warning: bar philosophy. Might include ramblings, booze, chain smoking, and fried snacks.]

      And yet, gravity is still there.

      Even if simultaneity is relative, the phenomenon is still there, you know? You can claim something fell before or after another event, but you can’t really claim it didn’t fall. And you can’t claim two simultaneous events stopped being simultaneous if they’re stationary for you, so it’s less of a “truth is relative to ME! ME! ME!” and more of a “truth is relative to that speed”. It’s still an objective matter, not a subjective one.

      • psud@aussie.zone
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        2 days ago

        Individual control of truth is a superpower. It definitely violates causality, it also isn’t what those people really mean by “truth is subjective”

      • petrol_sniff_king@lemmy.blahaj.zone
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        3 days ago

        so it’s less of a “truth is relative to ME! ME! ME!”

        This, I think, is an argument that exists in your head only. An excellent example of relativity, if I’m being honest.

        I don’t understand why subjectivity makes people so uncomfortable. Like, people would fight each other over the objectively correct temperature for the AC of their building if you let them—I just, I don’t get it.

        • Lvxferre [he/him]@mander.xyz
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          3 days ago

          This, I think, is an argument that exists in your head only.

          This is blatantly false. The argument exists in the comment I wrote. If it existed only “inside my head”, you wouldn’t access it. Because nobody knows what’s “inside someone else’s head”, nor we (people in general) should lie = assume = bullshit otherwise.

          An excellent example of relativity [SIC - subjectivity], if I’m being honest.

          Also false. While I believe my argument is correct, there’s also the chance it’s incorrect. If it is correct, my belief is true. But if it is incorrect, it won’t magically become “true for ME! ME! ME!”; I’d be simply holding a false belief. But either way, that depends on the argument itself, not on the fact I’m the one voicing it or analysing it or whatever. The subject here (me) still doesn’t fucking matter. And that’s bloody common sense.

          I don’t understand why subjectivity makes people so uncomfortable. [implied* by context: “relativity makes lvxferre uncomfortable”.]

          Okay… first off, let me address the most pressing matter: in no moment you showed that this “truth is subjective” babble would be even remotely true.

          Secondly. You’re making a bloody mess of “relativity” and “subjectivity”, as if both were synonymous. Get shit right dammit — subjectivity is a specific type of relativity regarding the subject. Showing time is relative to speed does jack shit to prove things would be relative to the subject, i.e. “gravity is false for me lol I’m jumping from the building!”.

          Thirdly. Why are you bullshitting = assuming = lying about what I’m comfortable or not with? You have no way to know it, don’t lie you do. I’m not uncomfortable with subjectivity. I simply consider it such inane bullshit, that I’m outright mocking it. Just like I’d mock flat Earth, souls, zodiacal signs, aliens visiting Earth on weekends, et cetera.

          Finally, drop off the Reddit style sealion: “I dun unrrurstand” followed by bullshit? Seriously, keep this shit in Reddit.

          Like, people would fight each other over the objectively correct temperature for the AC of their building if you let them—I just, I don’t get it.

          Gotta love assumptions…

          Not wasting my time further with you.

          *see Gricean maxims, specially the one of relevance.

          • petrol_sniff_king@lemmy.blahaj.zone
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            3 days ago

            Showing time is relative to speed does jack shit to prove things would be relative to the subject,

            With this attitude, I just don’t feel like you’d be living up to Einstein’s manner of thinking. Just too rigid.

            in no moment you showed that this “truth is subjective” babble would be even remotely true.

            Uh. Subjectively, I think it’s true.

            I really don’t think you even understand what I was trying to say with all that.

            i.e. “gravity is false for me lol I’m jumping from the building!”.

            Who is saying this?

    • marcos@lemmy.world
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      3 days ago

      If you jump out of a bridge, you will still break your face on the ground for every reference frame outside of a black hole.

    • Cethin@lemmy.zip
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      2 days ago

      Sure, if you’re traveling near the speed of light. For everyone on Earth, no one has ever experienced this (beyond a micro level that doesn’t matter and no one is discussing).

        • petrol_sniff_king@lemmy.blahaj.zone
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          22 hours ago

          Your head ages faster than your feet do! :D

          By such a small amount that it would never, ever matter, but it’s still cool to know!

          This small difference does actually become relevant when trying to explain gravity, though.

          As I’m sure you’ve heard, objects in free-fall do not feel an acceleration. Instead, objects in an inertial frame travel along straight world lines through curved spacetime “down” toward the gravitational source. Light is “pulled” into large objects because that’s what a straight line looks like to a light beam.

          I have a question, though: why is that I can’t feel gravity during a free-fall, but I can feel my own weight when standing on the Earth? Isn’t that kinda weird?

          (I’m wrapping the rest in a spoiler tag out of mercy to mobile users.)

          Tap for more paragraphs.

          Wouldn’t everything I just said suggest that if I can feel the direction of gravity, it must be because I’m accelerating somehow? If I were blind and in free-fall, I wouldn’t be able to tell what direction “down” even is, and yet, the muscles in my legs tell me very explicitly that they are “lifting” me.

          The answer, or a very useful answer, anyway, is that something is accelerating: the ground. The stationary ground accelerates up through curved spacetime to push me. That’s how I can tell.

          But how does the ground accelerate without moving? Shouldn’t the Earth expand if it’s accelerating?

          We’re definitely approaching the limit of the things I can explain at the moment, but the key is time dilation. The fact that your head ages faster than your feet is the reason why the Earth doesn’t expand. It accelerates without moving because time is also curved.

          You can think of it this way: If you were to graph the position of objects through time, the Earth’s surface might curve toward the y-axis, the time axis, because it is accelerating. But, the y-axis also curves “away” from the Earth’s surface in the same way, such that they maintain their distance. And so, the Earth doesn’t appear to move.

          Isn’t that cool?