this post was submitted on 13 Apr 2024
468 points (96.4% liked)

Science Memes

10988 readers
2061 users here now

Welcome to c/science_memes @ Mander.xyz!

A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.



Rules

  1. Don't throw mud. Behave like an intellectual and remember the human.
  2. Keep it rooted (on topic).
  3. No spam.
  4. Infographics welcome, get schooled.

This is a science community. We use the Dawkins definition of meme.



Research Committee

Other Mander Communities

Science and Research

Biology and Life Sciences

Physical Sciences

Humanities and Social Sciences

Practical and Applied Sciences

Memes

Miscellaneous

founded 2 years ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] Chrobin@discuss.tchncs.de 12 points 7 months ago (6 children)

Gravity isn't a force tho...

[–] JohnDClay@sh.itjust.works 16 points 7 months ago (1 children)

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 2 points 7 months ago (1 children)

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 1 points 7 months ago (1 children)

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 0 points 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 14 points 7 months ago* (last edited 7 months ago)

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

[–] quicksand@lemm.ee 10 points 7 months ago (2 children)

Yes it is. We just don't know what makes it work

[–] Chrobin@discuss.tchncs.de 3 points 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.

[–] JillyB@beehaw.org 2 points 7 months ago (1 children)

I'm no scientist, but there is some debate about whether it's a fundamental force. Some think it might be like centrifugal force which isn't "real" but shows up in a certain reference frame. Gravity might actually be a result of thermodynamics and entropy.

[–] oce@jlai.lu 1 points 7 months ago* (last edited 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 8 points 7 months ago (1 children)

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.

[–] bwrsandman@lemmy.world 2 points 7 months ago (1 children)

But is it fundamental though?

[–] cynar@lemmy.world 5 points 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 6 points 7 months ago (1 children)

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 1 points 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.

[–] JizzmasterD@lemmy.ca 3 points 7 months ago

Don’t be saucy