Does Gravity Swirl? Why? Researching the Truth

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Discussion Overview

The discussion centers around the concept of whether gravity has a swirling effect on space-time, as suggested by some visual representations. Participants explore the idea of frame dragging and its implications within the framework of general relativity, questioning the nature of gravity and the reasons behind such phenomena.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant recalls a visual representation of gravity swirling space-time but struggles to find references supporting this idea.
  • Another participant suggests that the concept may relate to frame dragging, referencing external material for further reading.
  • It is noted that while the swirling effect may be correct, the precision of measurements related to it is currently poor.
  • Participants discuss that science typically cannot answer "why" questions about gravity without a more fundamental theory, emphasizing the role of energy, momentum, and stress in general relativity.
  • The Kerr metric and Kerr black holes are mentioned as solutions that describe the swirling effect around rotating massive bodies.
  • Questions arise regarding the methodologies used in the Gravity Probe B mission, particularly concerning the accounting for various gravitational influences.

Areas of Agreement / Disagreement

Participants express uncertainty about the swirling effect of gravity, with some proposing connections to established concepts like frame dragging, while others question the ability to definitively explain the underlying reasons for such phenomena. No consensus is reached on the existence or implications of gravity swirling.

Contextual Notes

Limitations include the current lack of precision in measurements related to the swirling effect and the unresolved nature of "why" questions in the context of general relativity.

SuperM4ssive
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I vaguely remember learning somewhere somehow sometime that gravity doesn't just dent space-time inwards, it also swirls space-time just a bit. I remember learning this because it was visually depicted using honey. However, now that I try to find out more, I can't seem to find any reference to this swirling effect at all, either positive or negative. It's simply never mentioned. Is it actually true? And if so, why? Why does gravity swirl?
 
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It appears to be correct, but the current precision of the relevant measurement is pretty poor.

http://en.wikipedia.org/wiki/Gravity_Probe_B

As far as "why", science cannot really answer "why" questions, except in terms of a more fundamental theory. Currently, general relativity is our fundamental theory of gravity, so we cannot answer "why" questions about it until we develop a more fundamental theory.

What we can answer is "how". Energy, momentum, and stress all contribute to gravity in GR through the EFE. This is different from Newtonian gravity where momentum does not contribute.
 
Also check wikipedia and google for the "Kerr metric" and "Kerr black holes"; that's the solution that describes the swirling/frame-dragging effect around a massive rotating body.
 
DaleSpam said:
It appears to be correct, but the current precision of the relevant measurement is pretty poor.

http://en.wikipedia.org/wiki/Gravity_Probe_B

As far as "why", science cannot really answer "why" questions, except in terms of a more fundamental theory. Currently, general relativity is our fundamental theory of gravity, so we cannot answer "why" questions about it until we develop a more fundamental theory.

What we can answer is "how". Energy, momentum, and stress all contribute to gravity in GR through the EFE. This is different from Newtonian gravity where momentum does not contribute.

Do you know more about this missions? How did they account for quadrupole and higher "pole" from the asymmetry of the earth? How did they account for the effects of the sun and moon on the probe?
 

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