Theory of General Relativity: Reason for Heavenly Bodies Creating Spacetime Dent

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Discussion Overview

The discussion revolves around the nature of gravity as described by the theory of general relativity, specifically questioning why heavenly bodies create a dent in the spacetime fabric. The scope includes conceptual exploration and theoretical reasoning regarding gravity and spacetime.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant compares the dent created by heavenly bodies in spacetime to a metal ball creating a depression in an elastic sheet, questioning the underlying reason for this phenomenon.
  • Another participant suggests that a dent can also be created by accelerating the spacetime fabric, proposing that gravity may not be necessary to explain the deformation of spacetime.
  • A different participant expresses skepticism about ever finding a fundamental explanation for why heavenly bodies create dents in spacetime, arguing that if a theory is fundamental, it may not require further explanation.
  • One participant links the inability to answer such questions to the advocacy of "intelligent design" as a catchall explanation for scientific uncertainties.

Areas of Agreement / Disagreement

Participants express differing views on the nature of gravity and the explanation of spacetime deformation, with no consensus reached on the fundamental reasons behind these phenomena.

Contextual Notes

The discussion highlights the limitations in understanding the fundamental nature of gravity and spacetime, with participants acknowledging the complexity and potential for unresolved questions within the theory of general relativity.

Rainbow
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THE THEORY OF GENERAL RELATIVITY states that the gravitation is due to the fact that the heavenly bodies create a sort of dent in the spacetime fabric.

Now,
WHAT IS THE REASON THAT THE HEAVENLY BODIES CREATE SUCH KIND OF A DENT?

Let us for example take an elastic sheet and place metal ball on it. The ball will make a depression in the elastic sheet.

But, the ball creates that dent because something (i.e. the gravity of the earth) is pulling it and forcing it to create such kind of dent.

So, I repeat my question-
What is the reason that the heavenly bodies (like stars, planets, etc) create such kind of a dent in the spacetime fabric?
 
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The ball will also create a dent if the fabric is accelerated - for example, consider a 1 meter square sheet of spacetime fabric in free space and a queball located at the center - now grab the four corners and accelerate the fabric - the inertia of the queball will deform the fabric. You don't need gravity to explain gravity. If you consider the Hubble sphere as having a radial expansion c, then the Hubble volume is accelerating - and the amount of acceleration is consistent with the gravitational constant - which incidentally has units of volumetric acceleration per unit mass.

But one shouldn't take the analogy too far - the idea of a stretching spacetime fabric is metaphorical
 
Last edited:
Rainbow said:
WHAT IS THE REASON THAT THE HEAVENLY BODIES CREATE SUCH KIND OF A DENT?

...

But, the ball creates that dent because something (i.e. the gravity of the earth) is pulling it and forcing it to create such kind of dent.

So, I repeat my question-
What is the reason that the heavenly bodies (like stars, planets, etc) create such kind of a dent in the spacetime fabric?

Good question, I think we'd all like to know the answer to that. I doubt we ever will though. By definition: if a theory is fundamental, there is no further explanation possible. Only if relativity is ultimately shown to be part of an even more fundamental theory will it be superceded.

Even with your description of the ball and the dent caused by gravity, nothing is answered - because you think it is a "reasonable" explanation not requiring further elucidation. But any theory of gravity comes back to exactly the same question: Why?
 
It is questions like this that lead to people advocating "intelligent design". That is the catchall answer to any question which science is unable to answer (at this moment).
 
See this thread generally, and posts #4 ff specifically.
 

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