Could Gravity Ever Be Repulsive? Exploring Theories and Possibilities

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    Gravity Repulsion
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Discussion Overview

The discussion explores the possibility of gravity being repulsive under certain conditions, particularly at very small scales such as the Planck length. Participants consider theoretical implications, potential models, and the relationship between gravity and other forces, including dark matter interactions.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Theoretical speculation

Main Points Raised

  • Some participants question the asymmetry of gravity, suggesting that it could be repulsive at very small lengths, potentially resolving issues like singularities in black holes.
  • One participant references the nuclear force, proposing that the presence of strongly interacting particles might obscure the detection of gravitational forces at small distances.
  • Another participant asserts that there is no evidence supporting the idea of gravity being repulsive or changeable, although they acknowledge the asymmetry of gravitational attraction.
  • Concerns are raised about the behavior of dark matter, questioning why it does not clump together if it only interacts gravitationally, with one participant suggesting that angular momentum and scattering cross sections could explain this phenomenon.
  • A theoretical concept of negative mass is introduced, with a suggestion that dark matter may have its own interactions that could lead to repulsive effects.

Areas of Agreement / Disagreement

Participants express a range of views, with no consensus on the possibility of repulsive gravity. Some support the idea while others firmly state that there is no evidence for it. The discussion remains unresolved regarding the implications of dark matter interactions.

Contextual Notes

Participants note the limitations of current experimental data at very small scales and the challenges in detecting gravitational forces among strongly interacting particles. The discussion also touches on the speculative nature of negative mass and its implications for existing theories.

Riogho
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Every other force attracts and repels, gravity does not. Gravity only attracts. This is assymmetrical. We like to assume things that are not symmetrical are wrong. Why do we not assume this is wrong?

Is there any possible way gravity could be repulsive? I know there is staggering amounts of evidence to suggest it isn't, but why not on very small lengths, say Planck length, that gravity actually becomes repulsive.

Maybe the repulsion is just "gravitons" get so thick in an exchange between two particles it just pushes them away to a very small length until the density of them goes down.

Things like this idea would solve the idea of a singularity existing at the center black holes and such.

Do we have any experimental data at such small scales? Do we have anything that disproves an idea like this?

Just wondering.
 
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Search for the phrase "The nuclear force is only felt among hadrons. At much smaller separations between nucleons the force is very powerfully repulsive," in

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

How could anyone find a gravitational force at small distances with strongly interacting particles around? Perhaps using weakly-interacting non-electromagnetic particles?

Bob S
 
there's no evidence that gravity can be repulsed or even changed.
Yes that doesn't fit into the pattern but that's not a very good reason to base anything on.
 
Bob S said:
How could anyone find a gravitational force at small distances with strongly interacting particles around? Perhaps using weakly-interacting non-electromagnetic particles?

Bob S

Maybe the inability to see it is why we think it isn't there. Perhaps there is some way to assume what it is SUPPOSED to be, and we can see if there is any difference between that and what we experimentally see. Maybe the difference is gravity.

Because gravity is very weak anyway, the repulsion would logically be weak.

Also, on another related question (so as not to make another thread), if dark matter only interacts through the gravitational force, why is it not all just clumped together in one spot? Since there is no electromagnetic force to repulse it.
 
Riogho said:
if dark matter only interacts through the gravitational force, why is it not all just clumped together in one spot? Since there is no electromagnetic force to repulse it.
A negligible scattering cross section plus remanent angular momentum of individual dark-matter particles around galactic centers will prevent clumping.
Bob S
 
Last edited:
A point in space where the total magnitude of energy is less than zero from our frame of reference. Better known as the theoretical negative mass. Let's just say physics isn't directly touching that subject yet, but there are people thinking about it.

Oh and it's pretty arrogant to assume dark matter doesn't contain it's own particles of time interaction capable of repulsing each other. Do you really think everything is just made of protons/neutrons/electrons?
 

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