Is gravity a force or just a consequence of mass?

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Discussion Overview

The discussion revolves around the nature of gravity, questioning whether it is a force or merely a consequence of mass deforming spacetime. Participants explore the classification of fundamental forces in nature, particularly in the context of classical mechanics and theories of everything (TOE).

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants propose that gravity is a result of mass deforming spacetime, questioning whether it should be classified as a force.
  • Others argue that the classification of forces may depend on the context, particularly whether one is using classical mechanics or more advanced theories.
  • A participant mentions that electromagnetism and the weak force have been unified, suggesting that the maximum number of distinct forces may currently be three, with ongoing efforts to unify gravity with the other forces.
  • There is a suggestion that terminology used in classical mechanics can be confusing when applied to quantum mechanics, leading to ambiguity in the discussion of forces.
  • One participant notes that the question of whether gravity is a force may not have a definitive answer without a theory of everything (TOE) that fully integrates gravity with other fundamental forces.
  • Another participant emphasizes that the question is not easily answerable due to its reliance on vague language rather than precise mathematical models.

Areas of Agreement / Disagreement

Participants express differing views on whether gravity should be considered a force, with no consensus reached. The discussion remains unresolved regarding the classification of forces and the implications of different theoretical frameworks.

Contextual Notes

Participants acknowledge that the definitions of "force" can vary significantly depending on the theoretical framework being used, which complicates the discussion. There is also recognition that the depth of the approach required for a problem influences how gravity is perceived in relation to other forces.

CuriousGeorge1
Since gravity is caused by mass deforming spacetime, is gravity actually a force or just a consequence? Are there really 4 forces in nature or just 3?
 
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What does "really" mean?
 
“Really” used for emphasis, drop the word and question still stands. Are there four forces in nature or just 3?
 
CuriousGeorge1 said:
“Really” used for emphasis, drop the word and question still stands. Are there four forces in nature or just 3?
What do you mean by "forces"?

The point is that your question is not answerable because it is based on a false assumption: that you can frame a question about physics in vague ordinary language that somehow has a precise answer. The only precise answer is the mathematical models that physicists use to make predictions, and those models can be described in vague ordinary language in multiple, different ways. There is no one "right" description that will answer your question one way or the other.
 
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CuriousGeorge1 said:
Since gravity is caused by mass deforming spacetime, is gravity actually a force or just a consequence? Are there really 4 forces in nature or just 3?
Electromagnetism and the weak force have been unified, so the max right now is three. The goal with TOE is to get it all down to just one. Connecting the Strong force to Electroweak seems close. Getting Gravity to play along looks harder. But really anything is possible.

https://en.wikipedia.org/wiki/Grand_Unified_Theory
https://en.wikipedia.org/wiki/Theory_of_everything

In the narrower sense of "Is gravity a force?", you'd really need to have the TOE to get a final answer to that. Otherwise it starts turning into linguistics. Right now I'm not aware of any real objection to calling Gravity a force, (particularly for practical applications such as spacecraft ) but that might change someday.
 
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CuriousGeorge1 said:
is gravity actually a force or just a consequence?
'Force' as a construct in physics actually belongs to the specific viewpoint of 'Classical mechanics' and is not necessarily present in some alternative ... approaches.
If your actual approach is based on classical mechanics (likely the case when you work with everyday problems), then it's a force, and since classical mechanics has not much to do the unified theories, you may need to account for quite disturbing number of 'forces in nature'.

If the problem you are working with requires a more sophisticated approach, then gravity will be more and more like a consequence, and depending on the depth required by the problem, you might be down to three or just two forces interactions.

All depends on the required depth of the approach, and these answers are still the same without any controversy.
It's just ... not simple.
 
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Yeah, this might sound perplexing, but we often use terminology that was formerly used in classical mechanics that is also confusingly being used in quantum mechanics. Consider many of the terminology used in quantum mechanics to have certain context to what it actually refers to.

Even in the most simplest thing like Coulomb force Interaction (between electrons), which you may have a fairly good understanding in electromagnetism, will have a relatively math-heavy formulation in quantum mechanics (i.e. direct term and exchange term). However, few people confusingly call these terms as "direct force" and "exchange force". And then you have words like "force carrier" which is something else. So like everyone just stated here, "force" really depends on the context, and at what mathematical formulation we're exactly talking about.
 
Thanks to all of the above respondents for your replies. i was only considering force in relation to classical physics and TOE efforts to unify gravity with the strong/weak/EM forces. I now see my question in a broader context.
 

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