Is Gravity a force or the chape of spacetime?

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Discussion Overview

The discussion revolves around the nature of gravity, specifically whether it should be understood as a force or as a curvature of spacetime. Participants explore the implications of both perspectives, touching on theoretical, conceptual, and mathematical aspects of gravity.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Mathematical reasoning

Main Points Raised

  • Some participants propose that gravity is a curvature in spacetime caused by mass, suggesting that massive objects create a "dent" in spacetime that affects how other objects move.
  • Others argue that Newtonian gravity is treated as a force, while Einsteinian gravity is described as curvature, noting that both descriptions can be valid in different contexts.
  • A participant questions why gravity is often described as a force if it is fundamentally a curvature of spacetime, suggesting that the two descriptions are not mutually exclusive.
  • There is a discussion about the search for a graviton as a potential force carrier for gravity, with some participants noting that gravity is the least understood of the fundamental forces and that there may be untested mathematical theories regarding it.
  • One participant highlights the excitement surrounding the potential discovery of gravitons, comparing it to the discovery of the Higgs boson, while also acknowledging the limitations of current understanding of fundamental entities like forces and mass.
  • Concerns are raised about the completeness of current mathematical descriptions of forces, suggesting that there may be more aspects to gravity yet to be discovered.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether gravity is a force or a curvature of spacetime, with multiple competing views remaining. The discussion reflects a range of opinions on the nature of gravity and the implications of each perspective.

Contextual Notes

Participants express uncertainty regarding the completeness of current theories and the nature of gravitational interactions, indicating that the discussion is limited by existing knowledge and observational constraints.

tkav1980
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From my understanding Gravity is a curvature in space-time caused by mass. basically a massive object makes a dent in space and the curvature of that dent is relative to the size of the object vs. its mass(red giant vs black hole). A smaller but more massive object will make a deeper dent.

But, if gravity is only a curvature of space-time and not a force, why is it so often decsribed as a force? Why would physicist be looking for a force carrier/ particle for gravity?
 
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Newtonian gravity is a force, Einsteinian gravity is a curvature of spacetime.

99% of the time, it is perfectly OK to treat gravity as Newton did - as a force (just like 99% of the time it is perfectly OK to treat velocity as Newtonian - without relativistic effects). In both cases, the differences between Newton and Einstein are vanishingly small.

It is far easier to calculate the orbit of a satellite or the trajectory of a bullet by using forces than by using spacetime curvature equations.But 1% of the time, when you get to the leaky margins of science, such as very high gravity (or very large velocities), Newtonian mechanics start to fall apart.
 
tkav1980 said:
But, if gravity is only a curvature of space-time and not a force, why is it so often decsribed as a force?
The two descriptions are not mutually exclusive. In any case where the description as a force works, the description as curvature also works.
 
Why would physicist be looking for a force carrier/ particle for gravity?

For one thing physicsts have more possible mathematical theories than observations can so far confirm. A lot don't work...that is, are repudiated by observation...but some are untested experimentally.

It's good keep in mind gravity is so far the least understood of the fundamental forces. So far the other three forces in our models exchange particles so maybe there is a mathematical description with a graviton that can be confirmed. Right now I'd maintain that our understanding of any of the basic entities (forces, mass, time, space, etc) is limited so we continue to search for other perspectives. I guess finding/confirming gravitons might be as exciting as finding the Higgs boson (a proposed particle responsible for mass).

And if a graviton exists, it must be a remarkable particle: it seems like the only one that can't be blocked...or does that apply to the Higgs boson as well?? Anyway, the other forces of the Standard Model can be negated.

Besides, just because our current mathematical descriptions fit the strong, weak, and electromagnetic forces we observe (to the experimetal limits we can detect) doesn't mean they are the final (complete) descriptions.

Since light so far seems to sometimes be an E wave, sometimes a B wave, sometimes a photon, who knows how many aspects we might ultimately find for gravity.
 
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