Gravity: Attraction of Two Particles vs. Two Objects

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Discussion Overview

The discussion revolves around the nature of gravity, specifically whether it can be simplified to the attraction between two particles of equal mass rather than considering the attraction between two massive objects. Participants explore the implications of this simplification on the calculation of gravitational attraction and its dependence on the distribution of mass within objects.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions if gravity can be simplified to the attraction of two equal mass particles and whether this requires calculating the relative positions of all particles for accuracy.
  • Another participant suggests that gravitational attraction is dependent on the amount of mass present, noting that the center of gravity varies with the shape of objects.
  • A different viewpoint presents the idea that the computation of gravitational attraction between two arbitrary bodies involves integrating over infinitesimal mass elements, which accommodates non-uniform mass distributions.
  • One participant emphasizes that gravity is fundamentally an attraction between particles and highlights its relative weakness compared to other fundamental forces, while also noting that the cumulative effect of many particles leads to significant gravitational forces at large scales.
  • The same participant raises a question about measuring the "continuity" of gravity's strength topologically and references the GRACE mission, which detects geophysical features related to Earth's gravity field.

Areas of Agreement / Disagreement

Participants express differing views on whether gravity can be simplified to the attraction of two particles and the implications of such a simplification. There is no consensus on the best approach to understanding gravitational attraction, and multiple competing perspectives remain in the discussion.

Contextual Notes

Participants mention the uneven distribution of mass within the Earth and its effects on gravitational measurements, indicating that the discussion may be limited by assumptions about uniformity and the complexity of gravitational interactions.

imi
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Can the theory of gravity be simplified to the attraction of two particles (always of equal mass) rather than the attraction of two massive objects?

If so would the relationship of gravitational attraction have to be calculated according to the relative position of all particles in an object in order to be completely accurate?
 
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Seems that way if gravitational attraction is a function of how much mass is present. That's why the center of gravity is different for differently shaped objects.
 
In general the computation of gravitation attraction between 2 arbitrary bodies takes the form of an integral, where each body is subdivided into infinitesimal mass elements. This approach can correctly compute the attraction between bodies which do not have uniform mass distributions.
 
gravity is a basic attraction between two particles. It is the weakes fore of the 4 elementary forces in the universe; gravitational, electromagnetic, weak nuclear and stong nuclear. It is actually millions of times weaker than the other three, but since matter is made up od soo many billions and billions of particles, the gravitational forces add up and dominate in the large scale world.
 
Nenad said:
gravity is a basic attraction between two particles. It is the weakes fore of the 4 elementary forces in the universe; gravitational, electromagnetic, weak nuclear and stong nuclear. It is actually millions of times weaker than the other three, but since matter is made up od soo many billions and billions of particles, the gravitational forces add up and dominate in the large scale world.

Is there a way to measure the "continuity" of the strength and weakness of gravity topologically?

I have placed GRACE here in posts for consideration to reveal the topological features of earth

http://www.csr.utexas.edu/grace/gallery/gravity/03_07_GRACE2.jpg
These detailed geophysical features are being detected by GRACE with no surface gravity measurements. (July 21, 2003)

http://www.csr.utexas.edu/grace/gallery/animations/world_gravity/

Due to an uneven distribution of mass inside the Earth, the Earth's gravity field is not uniform - that is, it has "lumps". By far the largest is a flattening at the poles, called the Earth's oblateness, but in this model we've greatly exaggerated the scale so that many smaller features can be seen. The GRACE Mission will map out the precise location and size of these lumps, enabling greater understanding of the structure of the Earth. Additionally, GRACE will monitor the mass and location of water as it moves around on the surface of the Earth, cycling between the land, oceans, and polar ice caps.


I have also place information in terms of gravity Probe B in other posts. Sci physics strings as well
 

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