Why is it a problem that gravity is so much weaker than the other forces?

  • Context: Graduate 
  • Thread starter Thread starter camel_jockey
  • Start date Start date
  • Tags Tags
    Forces Gravity
Click For Summary

Discussion Overview

The discussion revolves around the perceived problem of gravity being significantly weaker than the other fundamental forces, particularly in the context of theoretical physics and experimental measurement. Participants explore the implications of this weakness, its conceptual understanding, and its impact on scientific inquiry.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants suggest that gravity, as described by general relativity, is a fictitious force arising from curved spacetime, which differentiates it from the other fundamental forces that are considered "real."
  • There is a question raised about the discomfort regarding gravity's weakness compared to other forces, with one participant expressing confusion about why this is considered a problem.
  • Another participant challenges the notion of discomfort, stating they do not find the weakness of gravity problematic and questioning the basis for such a claim.
  • Some theorists and quantum field theorists have mentioned the weakness of gravity as a problem, though one participant expresses uncertainty about whether it truly is a problem.
  • A participant notes that the weakness of gravity complicates experimental measurements, as it is often overpowered by other stronger forces, making it difficult to detect gravitational effects in practical scenarios.
  • One participant highlights the existence of a dimensionless constant that illustrates the disparity in strength between gravitational and electromagnetic forces, suggesting that this discrepancy complicates the derivation of gravity's strength from first principles.

Areas of Agreement / Disagreement

Participants express differing views on whether the weakness of gravity is a problem. Some acknowledge it as a significant issue in theoretical discussions, while others do not see it as problematic at all. The discussion remains unresolved regarding the implications of gravity's weakness.

Contextual Notes

Limitations include the lack of consensus on the implications of gravity's weakness and the varying interpretations of what constitutes a "problem" in this context. There are also unresolved questions about the ability to derive gravity's strength from fundamental principles.

camel_jockey
Messages
37
Reaction score
0
I will write the following as if I know what I am talking about, feel free to correct me :)

Okay, so we have theorized (using general relativity) that the force of gravity is in fact a fictitious force, resulting from observing motion in a curved spacetime. It is therefore unlike the other forces, which are considered to be real in the sense that they are not illusions resulting from poor observation.

Also, gravity is purely an attractive force, and therefore also fundamentally different to the other 3 forces.

Why then do we think it uncomfortable that gravity is "10^-38 times weaker" than the strong force, or whatever the factor is (we all know it to be small)??

Is it not totally OK, since gravity isn't a force and we shouldn't be making this comparison?

Or does this stem from the desire to have gravity, whatever it may be, being mediated by some force-carrying particle such as the graviton??

I don't understand really why it is considered a problem, but I have heard people talking about it. Would be nice if someone could explain the crux of the matter to me.
 
Physics news on Phys.org
?? I don't have any problem with it and I surely am not "uncomfortable" with the force of gravity being so small. In fact, I fell sure I would be extremely uncomfortable if it were 10^38 times stronger!

Please give some specific examples in which it is considered a "problem".
 
In the sense that many theorists and QFTists have said that it is a problem - I don't know if it really is! That's the question!
 
In literature I came across, gravity being weak as a problem is often mentioned with relation to how hard it is to 'measure' or 'detect' gravity in experiments.

For one, the idea that a pill-size magnet overpower the gravity of a very big planet in preventing your keys from falling towards earth, goes to show what scale of bodies you need in order to experiment with gravity. Then, as other forces are much stronger, they might interfere with trying to 'measure' gravity.

My two pence.
 
The problem is that you can build a dimension-less constant in order of 10^38. For example, in H atom, proton and electron attract gravitationally 10^38 times weakes than electomagnetically.

The problem is that is ruins any hope to deduce that huge number from the first principles. It can't be PI, or PI^PI, or even exp(exp(PI)) or something. While all other parameters of the Standard Model are in the same range (expect neutrino masses, but there is an explanation), and even some parameters can be calculated (Koide formula - http://en.wikipedia.org/wiki/Koide_formula ) there is no hope that gravity will be ever explained that way.
 

Similar threads

Undergrad Why is gravity a fictitious force?
  • · Replies 123 ·
5
Replies
123
Views
5K
Undergrad Gravity: Force or Acceleration?
  • · Replies 69 ·
3
Replies
69
Views
8K
High School Is Gravity Really a Force Like the Other Fundamental Forces?
  • · Replies 12 ·
Replies
12
Views
2K
Graduate Is Fatio–Le Sage's theory of gravitation an entropic gravity?
  • · Replies 33 ·
2
Replies
33
Views
3K
High School Does Gravity Act on Everything? Fundamental to GR?
  • · Replies 8 ·
Replies
8
Views
2K
High School Gravitational Force acting on a massless body
  • · Replies 67 ·
3
Replies
67
Views
6K
High School Unifying Non-Gravity Forces & Spacetime Warping
  • · Replies 15 ·
Replies
15
Views
2K
Undergrad Doubts about the relativistic description of electrical interactions
  • · Replies 2 ·
Replies
2
Views
1K
Undergrad Explanation for Galaxy Rotation Curves
  • · Replies 12 ·
Replies
12
Views
2K
Undergrad Is Gravity a Force or Curvature?
  • · Replies 20 ·
Replies
20
Views
6K