• JohnDClay@sh.itjust.works
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      7 months ago

      I put it in my force balance equations, it’s a force. It doesn’t matter that it’s from curving spacetime rather than exchanging particles, it still exerts force on things.

      • Chrobin@discuss.tchncs.de
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        7 months ago

        But the point of general relativity is that a free-floating observer is equivalent to an observer in free space. That means that falling due to gravity, which you call a force, is an unaccelerated movement, i.e. no force.

        • JohnDClay@sh.itjust.works
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          7 months ago

          If I take a relativistic frame of reference. If I take an ‘absolute’ non moving frame of reference, gravity shows up as a force. I use the later for calculating loads and statics, even though it’s technically not correct. And in that case gravity shows up as a force.

          • Chrobin@discuss.tchncs.de
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            7 months ago

            I’m not trying to argue approximations. Physics is just approximations all the way down. But as a physicist, I also love arguing about technicalities, and that’s also kinda the point of science communities for me.

    • Zerush@lemmy.ml
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      7 months ago

      Well, its a geometric deformation of space-time because the displacement by mass

      • Chrobin@discuss.tchncs.de
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        7 months ago

        In our current understanding of physics, it’s an effect from the curvature of space and not a force. Quantizing gravity results in unphysical divergences. Whether there will be a way to model gravity as an exchange of particles, we can’t know for sure. So according to our current knowledge, it’s not a force.

        • oce 🐆@jlai.lu
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          7 months ago

          There are many things than we experience as distinct forces but may not be actually if you change the reference (ex: centrifugal force is inertia) or if you go deeper into unification (ex: electrostatic force and magnetic force can be unified into electromagnetic force). But physics is about modeling reality in a convenient way for you current reference, we will never be certain to have the “real” final model independent from our observation bias.

    • cynar@lemmy.world
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      7 months ago

      Knowledge is knowing that tomato is a fruit.

      Wisdom is still not putting it in a fruit salad.

      Gravity isn’t a force. Its effects can be mapped to an equivalent pseudo force and used as such. Outside of general relativity, or Quantum mechanics discussions, gravity is a force.

        • cynar@lemmy.world
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          7 months ago

          We don’t know. Right now, relativity and QM fundamentally disagree on what gravity is. Both are also hugely accurate in their predictions. QM treats it as a force comparable to EM or the strong force. GR says it’s space itself moving. The force we experience is just a reaction to us trying to stay still, as space moves through us.

          Beyond that, defining anything as fundamental is a challenge. How are you using fundamental?

    • oce 🐆@jlai.lu
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      7 months ago

      Depends on your definition. If you stop at quantum mechanics way of defining a force with boson exchange then you may also say gravity doesn’t exist, because it’s not included in the standard model for now.

      • Chrobin@discuss.tchncs.de
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        7 months ago

        Well, firstly, we can quantize gravity pretty easily, it just has unphysical divergences.

        But secondly, I think it makes most sense to talk about the current accepted physics because we don’t know how quantum gravity will work.