Is gravity a force or a lack of a force?

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Discussion Overview

The discussion revolves around the nature of gravity, specifically whether it acts as a force that pulls, or if it could also be interpreted as a lack of force or a repelling force. Participants explore concepts from Newtonian physics and general relativity, questioning the mechanisms behind gravitational attraction and the role of space in this phenomenon.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions if gravity could be a repelling force, suggesting that empty space might exert pressure on objects of mass.
  • Another participant argues against the idea of gravity as a repelling force, stating that Newton's third law implies equal and opposite reactions, which does not support repulsion.
  • A different viewpoint introduces the concept of mass creating "dents" in space, leading to interactions between fields that result in gravitational attraction.
  • Some participants reference general relativity and the analogy of warped space, questioning whether gravity is a result of warped space or if warped space is a consequence of gravity.
  • One participant expresses interest in the pressure theory of gravity and seeks further information on it.
  • Another participant presents a speculative idea that gravity could be a result of a lack of repelling action between massive bodies, suggesting an equilibrium state disrupted by the presence of another mass.

Areas of Agreement / Disagreement

Participants express differing views on whether gravity can be considered a repelling force, with some firmly rejecting this notion while others explore the idea. The discussion remains unresolved, with multiple competing views on the nature of gravity and its underlying mechanisms.

Contextual Notes

Participants reference concepts from Newtonian physics and general relativity without reaching consensus on the implications of these theories for understanding gravity. There are also mentions of speculative ideas that have not been widely accepted in the scientific community.

Ilikemyname
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My actual question is if gravity repels as well as pulls. I know, according to Newton's third law, that every action has an equal and opposite reaction. So can the force we label gravity actually be the result of the supposed empty space around it exerting pressure onto objects of mass?

[This question has been plaguing me as of late due to my swimmers ear.
I often lose balance when my inner ear goes off.]

This question probably sounds dumb to some, but I am new here so I was wondering if anyone had a quick answer.
 
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Ilikemyname said:
My actual question is if gravity repels as well as pulls.
I don't believe it does. I haven't studied general relativity, but from what I understand it produces only minor changes in the expected behavior of gravity in most situations.
Ilikemyname said:
I know, according to Newton's third law, that every action has an equal and opposite reaction.
Yes. This simply means that if the sun pulls the Earth with a force of so many Newtons, then the Earth pulls the sun with the same force. Niether repels the other.
Ilikemyname said:
So can the force we label gravity actually be the result of the supposed empty space around it exerting pressure onto objects of mass?
I don't see how a pressure force would behave like gravity. A pressure force would not cause the Earth to accelerate because it presumably pushes with the same force in every direction.
 
Thanks for the reply, Leon!

So there are "dents" created by any amount of collected mass, which can be concidered fields. Any other mass's field that rolls through or overlaps the first mass's field, then their two fields interact with one another exerting gravity. These two fields... pull on each other? why?

Now I know that GR thing. Like a trampoline with bowling balls on them, but in order for that experiment to work you need gravity in the first place.

Is gravity because of the warped space? Or is the warped space due to gravity?
 
Ilikemyname said:
My actual question is if gravity repels as well as pulls. I know, according to Newton's third law, that every action has an equal and opposite reaction. So can the force we label gravity actually be the result of the supposed empty space around it exerting pressure onto objects of mass?

[This question has been plaguing me as of late due to my swimmers ear.
I often lose balance when my inner ear goes off.]

This question probably sounds dumb to some, but I am new here so I was wondering if anyone had a quick answer.

The quick answer is no, gravity is not a repelling force.

See for instance the wikipedia article

http://en.wikipedia.org/wiki/LeSage_gravity

The only comment I have is that wiki was MUCH too kind to the cranks who are attempting to revive this dead horse of a theory.
 
I was wondering who had a good article on the pressure theory.
Thanks a lot Pervect.
I hope you don't find me a crank, I was just wondering.
 
It is interesting to try at least a little to verify this idea. That gravity is a repeling force and the attraction between massive bodies has to do with some lack of repeling action through the distance that conects the two bodies.

Imagine a massive body is constantly being shot by small particles. So if it is isolated, it will be in equilibrium. But if another body enter as a shadow creator then attractio happens
 
Ilikemyname said:
Is gravity because of the warped space? Or is the warped space due to gravity?

I think it's correct to say "gravity because of warped space. Warped space due to the presence of mass," but I haven't studied GR either.
 

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