Does the gravity constant change?

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Discussion Overview

The discussion revolves around the question of whether the gravitational constant changes over time, particularly in the context of the universe's expansion. Participants explore theoretical implications and potential consequences for applied science if such a change were to occur.

Discussion Character

  • Debate/contested
  • Exploratory
  • Conceptual clarification

Main Points Raised

  • Some participants suggest that the gravitational constant may change due to the expansion of the universe, raising questions about the implications for applied science.
  • Others argue that the general consensus is that the gravitational constant does not change, citing Brans-Dicke theory as one of the frameworks that propose variations in the constant.
  • One participant notes that if the gravitational constant were to vary significantly, it could lead to bizarre effects on stellar evolution and orbital mechanics.
  • Another participant posits that any change in the gravitational constant could have severe consequences for the stability of planetary orbits and the functioning of communication satellites.
  • Concerns are raised about the potential for extreme scenarios, such as a black hole "unforming," if the gravitational constant were to vary more than trivially.

Areas of Agreement / Disagreement

Participants express differing views on whether the gravitational constant changes over time, with some supporting the idea and others defending the consensus that it remains constant. The discussion remains unresolved with multiple competing perspectives presented.

Contextual Notes

Participants acknowledge that the implications of a changing gravitational constant could lead to significant alterations in physical phenomena, but the discussion does not resolve the underlying assumptions or definitions related to the gravitational constant.

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Does the gravity constant change slightly over time due to the expansion of the universe?

What would be the consequences to applied science if it did?
 
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The general consensus is that it don't change, but there always people trying to go against the mainstream; if not science would be very boring, don't you think? :redface:
One of the theories that postulates a variation of Newton Constant in space and time is Brans-Dicke theory.
What would be the consequences to applied science if it did?
You can imagine it: bad. Imagine a varying Newton constant in the vicinity of Earth. How positive can be it for our network of communication satellites?

This paper is interesting as postulates a varying Newton constant
Rippled Cosmological Dark Matter from Damped Oscillating Newton Constant
http://arxiv.org/abs/gr-qc/0409059
Saludos
 
Not exactly as phrased. Expansion weakens the tug between distant objects merely by increasing distance [gravity follows the inverse square rule like other forces]. Variations in gravity over time would have a lot of pretty weird effects, assuming the variance was more than trivial. Stellar evolution would be goofy, orbits would would be messed up, as meteor noted, even really weird stuff like a black hole unforming - I can't really even imagine what that would look like.
 
when the universe was created set values for, speed of light, gravity etc etc were all specific. They may change but it would either pull the planets into the sun or send them flying out into space.
 

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