Confused on Gravity: Is Gravitational Force Strong Enough for a Black Hole?

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Discussion Overview

The discussion revolves around the nature of gravity, particularly in the context of black holes. Participants explore the apparent contradiction of gravity being the weakest force while also being capable of creating conditions where nothing can escape, as seen in black holes. The conversation touches on theoretical aspects and conceptual clarifications regarding gravitational force and its cumulative effects.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants assert that gravity is the weakest force, questioning how it can lead to black holes where nothing escapes.
  • Others propose that gravity's cumulative nature allows it to become the strongest force as mass accumulates, leading to stronger gravitational fields.
  • One participant notes that the vast spaces between molecules contribute to the formation of black holes, suggesting that increased mass results in a denser gravitational field.
  • A participant clarifies that while gravity is the weakest of the four fundamental forces at short distances, it dominates at larger scales due to its always attractive nature.
  • Another participant challenges the claim about the weakening of other forces over distance, arguing that while gravity and electromagnetism both fall off as 1/r², gravity's consistent attraction gives it an advantage over long distances.

Areas of Agreement / Disagreement

The discussion features multiple competing views regarding the nature of gravity and its role in black holes. There is no consensus on the interpretations of gravitational strength and its implications.

Contextual Notes

Participants express differing interpretations of gravitational strength, the effects of distance on forces, and the implications for black hole formation. Some assumptions about the nature of forces and their interactions remain unresolved.

beeger
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I'm confused! Gravity is the weakest force...right. How is it possible to hypothesize that a black hole scenario of gravitation being stong enough that nothing else can escape?
 
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beeger said:
I'm confused! Gravity is the weakest force...right. How is it possible to hypothesize that a black hole scenario of gravitation being stong enough that nothing else can escape?
Because gravity is
1] cumulative (Every single particle pulls on every other particle.)
2] infinite in extent (the other forces act over extremely short distances.)
 
thankyou!
So as it accumulates it becomes the strongest force.
 
beeger said:
thankyou!
So as it accumulates it becomes the strongest force.

This is correct. Plus, there is a lot of space between the molecules that make up our planet, just as there is a lot of space that make up our sun.
As the gravitational body acquires more mass, it exerts a greater gravitational field. Ultimately, the increase in gravity condenses the molecules that make up the Earth and sun to such an extent that there is no space left in between the molecules that make up the Earth and sun. A very massive body + no room in between the molecules of the massive body = a black hole that excerts the strongest known force.
 
Hi there,

beeger said:
Gravity is the weakest force...right.

By saying the weakest force, you might want to precise. Gravity is the weakest of the four fundamental interaction, but for short distance only. By short distance, I mean from a few pm up to a few thousands (maybe millions km).

The greater the distance is, the weaker the other three interactions become. Therefore, on very large scale, only the gravitational interaction is left to do the work.

Cheers
 
fatra2 said:
The greater the distance is, the weaker the other three interactions become.

That's not true - or rather, it's true but misleading. Both EM and gravity fall off as 1/r2. The other two fall off faster. The reason that gravity wins out over large distances is that it is always attractive, whereas electromagnetism is sometimes attractive and sometimes repulsive.
 

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