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It wouldn’t surprise me if at some point in the future we realise mass shields us from a gravitational field that pushes everything in all directions at once as

It wouldn’t surprise me if at some point in the future we realise mass shields us from a gravitational field that pushes everything in all directions at once as opposed to our current thinking that mass emits a field that pulls us towards it. Eg. imagine the earth below you shielding you from a force that otherwise pushes all mass in all directions constantly. You’re now more shielded from the push in the direction of the earth so you feel pulled that way. It’s the same thing. Just a sign change from a convention we had no real basis to believe one way or the other.

bequanna 2y ago
As a layperson, that makes sense to me. It also explains the time dilation effect when near a large mass.
- AnotherGoodName 2y ago
  Thinking of it as directional action potentials that are blocked by mass? I agree it does feel intuitively nicer that way honestly.
  - bequanna 2y ago
    Yep. Coming from everywhere and moving outward in all directions at all times and ‘absorbed’ or ‘blocked’ by mass
    - marmadukester39 2y ago
      Physicists: Has anyone ever looked into this?
      - abecedarius 2y ago
        Yes. https://en.wikipedia.org/wiki/Mechanical_explanations_of_gravitation https://en.wikipedia.org/wiki/Mechanical_explanations_of_gra... (but I only play a physicist on HN)
ViktorRay 2y ago
Well I guess that explains why "the normal force" is the one that counteracts gravity. (for those of you who don't know, the super simplified explanation in physics 101 is that the normal force is the vector that pushes up while gravity pushes down for objects that are resting on top of each other) So I guess the one who named it "the normal force" would be more correct that he ever imagined if your theory of gravity was the real correct one!
hollerith 2y ago
Turn it into a theory that predicts exact quantities (accelerations) and I will start paying attention.
- ViktorRay 2y ago
  Well why wouldn’t it? The mathematical constants could remain the same as in the current theories. Both the constant G for gravitation and g for the acceleration for gravity on earth. I am not a physicist so I may be getting something wrong
  - hollerith 2y ago
    Newton's Philosophiae Naturalis Principia Mathematica (published 1687) contains a mathematical (geometric actually) proof that the gravitational attraction between the Earth an a man standing on the surface of the Earth is the same as it would be if all of the mass of the Earth were at its center. There's another proof that if the man is standing at the bottom of a one-mile hole, and the Earth is assumed to be a perfect sphere, then the attraction is the same as if the Earth's radius were one mile less than it actually is (i.e., the attraction between the man and the shell of mass higher in altitude than the man is exactly zero because the attraction from the various points in the one-mile-thick shell exactly cancel out). That is that kind of thing I mean: proofs and calculations, not "why wouldn't it?"
    - ViktorRay 2y ago
      Hey thank you for your reply. I learned several interesting examples from your first paragraph in the comment. I do think your last sentence here was unnecessary though: ”That is that kind of thing I mean: proofs and calculations, not "why wouldn't it?"” When I said “why wouldn’t it” I was asking out of genuine curiosity. There really wasn’t any need to criticize that part. It came off as maybe more hostile than I think you intended. Again I most certainly appreciate you taking the time to type up the rest of your comment though because I did learn quite a bit from those examples you posted so I am indeed sincerely grateful for that.
- 2y ago
atahanacar 2y ago
What you are describing is a meme in my country, used to make fun of religious anti-evolution people who claim "evolution is only a theory and not a proven law, thus doesn't exist". We call gravity "yer çekimi", which literally means "the pull of ground". The meme is "Ya yer çekimi yoksa da gök itimi varsa?" which translates to "What if the gravity doesn't exist but sky-push does?".
Joker_vD 2y ago
> It wouldn’t surprise me if at some point in the future we realise mass shields us from a gravitational field that pushes everything in all directions at once as opposed to our current thinking that mass emits a field that pulls us towards it. It would definitely surprise me since I know that this theory — since it's such an obvious hypothesis — has been proposed multiple times since Newton's own (it's now colloquially called "Le Sage's theory of gravitation" [0], but it had many other proponents including Kelvin, H. Lorentz and Thomson) and it has always failed to accomodate the equivalence of graviational and inertional masses: after all, the gravity is not proportional to the cross-section of the bodies, and graviational shielding does not exist — experiments done by Eötvös were quite decisive in that regard. [0] https://en.wikipedia.org/wiki/Le_Sage%27s_theory_of_gravitation https://en.wikipedia.org/wiki/Le_Sage%27s_theory_of_gravitat...

bequanna 2y ago

As a layperson, that makes sense to me. It also explains the time dilation effect when near a large mass.

AnotherGoodName 2y ago
Thinking of it as directional action potentials that are blocked by mass? I agree it does feel intuitively nicer that way honestly.
- bequanna 2y ago
  Yep. Coming from everywhere and moving outward in all directions at all times and ‘absorbed’ or ‘blocked’ by mass
  - marmadukester39 2y ago
    Physicists: Has anyone ever looked into this?
    - abecedarius 2y ago
      Yes. https://en.wikipedia.org/wiki/Mechanical_explanations_of_gravitation https://en.wikipedia.org/wiki/Mechanical_explanations_of_gra... (but I only play a physicist on HN)

ViktorRay 2y ago

Well I guess that explains why "the normal force" is the one that counteracts gravity. (for those of you who don't know, the super simplified explanation in physics 101 is that the normal force is the vector that pushes up while gravity pushes down for objects that are resting on top of each other) So I guess the one who named it "the normal force" would be more correct that he ever imagined if your theory of gravity was the real correct one!

hollerith 2y ago

Turn it into a theory that predicts exact quantities (accelerations) and I will start paying attention.

ViktorRay 2y ago
Well why wouldn’t it? The mathematical constants could remain the same as in the current theories. Both the constant G for gravitation and g for the acceleration for gravity on earth. I am not a physicist so I may be getting something wrong
- hollerith 2y ago
  Newton's Philosophiae Naturalis Principia Mathematica (published 1687) contains a mathematical (geometric actually) proof that the gravitational attraction between the Earth an a man standing on the surface of the Earth is the same as it would be if all of the mass of the Earth were at its center. There's another proof that if the man is standing at the bottom of a one-mile hole, and the Earth is assumed to be a perfect sphere, then the attraction is the same as if the Earth's radius were one mile less than it actually is (i.e., the attraction between the man and the shell of mass higher in altitude than the man is exactly zero because the attraction from the various points in the one-mile-thick shell exactly cancel out). That is that kind of thing I mean: proofs and calculations, not "why wouldn't it?"
  - ViktorRay 2y ago
    Hey thank you for your reply. I learned several interesting examples from your first paragraph in the comment. I do think your last sentence here was unnecessary though: ”That is that kind of thing I mean: proofs and calculations, not "why wouldn't it?"” When I said “why wouldn’t it” I was asking out of genuine curiosity. There really wasn’t any need to criticize that part. It came off as maybe more hostile than I think you intended. Again I most certainly appreciate you taking the time to type up the rest of your comment though because I did learn quite a bit from those examples you posted so I am indeed sincerely grateful for that.
2y ago

atahanacar 2y ago

What you are describing is a meme in my country, used to make fun of religious anti-evolution people who claim "evolution is only a theory and not a proven law, thus doesn't exist". We call gravity "yer çekimi", which literally means "the pull of ground". The meme is "Ya yer çekimi yoksa da gök itimi varsa?" which translates to "What if the gravity doesn't exist but sky-push does?".

Joker_vD 2y ago

> It wouldn’t surprise me if at some point in the future we realise mass shields us from a gravitational field that pushes everything in all directions at once as opposed to our current thinking that mass emits a field that pulls us towards it. It would definitely surprise me since I know that this theory — since it's such an obvious hypothesis — has been proposed multiple times since Newton's own (it's now colloquially called "Le Sage's theory of gravitation" [0], but it had many other proponents including Kelvin, H. Lorentz and Thomson) and it has always failed to accomodate the equivalence of graviational and inertional masses: after all, the gravity is not proportional to the cross-section of the bodies, and graviational shielding does not exist — experiments done by Eötvös were quite decisive in that regard. [0] https://en.wikipedia.org/wiki/Le_Sage%27s_theory_of_gravitation https://en.wikipedia.org/wiki/Le_Sage%27s_theory_of_gravitat...