Can Matter Shape the Metric in Analog Models of Gravity?

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    Analog Gravity Models
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SUMMARY

The discussion focuses on analog models of gravity, particularly the influence of matter on the metric in these models. It highlights the pursuit of detecting Hawking radiation in sonic black holes and questions whether there are analog models where the metric is shaped by matter according to the Einstein field equations. The conversation emphasizes that while gravity can be represented as a 2D elastic sheet, this model has limitations, such as the inability of very light objects to sink into the gravity well. The existence of black holes is acknowledged, but their proof remains elusive, with current understandings largely based on computer-generated models.

PREREQUISITES
  • Understanding of analog models of gravity
  • Familiarity with the Einstein field equations
  • Knowledge of Hawking radiation and its implications
  • Basic concepts of quantum field theory
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  • Research the implications of the AdS/CFT correspondence in analog gravity models
  • Explore the detection methods for Hawking radiation in sonic black holes
  • Study the limitations of 2D representations of gravitational fields
  • Investigate the current experimental approaches to proving the existence of black holes
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Physicists, researchers in gravitational theory, and students interested in the intersection of quantum mechanics and general relativity will benefit from this discussion.

petergreat
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In analog models of gravity, such as http://en.wikipedia.org/wiki/Acoustic_metric" , the motion of "matter" is influenced by the metric. Detection of Hawking radiation in sonic black holes is a goal that some experimental groups are working on. However, in GR geometry and matter act on each other. Are there analog models of gravity in which the metric is also shaped by "matter" via the Einstein field equation?
 
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But Hawking radiation is derived from quantum field theory on a fixed spacetime, isn't it?

I think there are analogue models in which at least some components of the metric are shaped by matter, but there are none in which the equation for the metric has the form of the Einstein equations (except for AdS/CFT)

http://arxiv.org/abs/0909.3834
 
As long as you aren't going into graviton theory, gravity is best described on a 2d plane and like an elastic sheet of material, as heavy objects (greater mass) sink deeper than those which are lighter, similar to gravity each object is affected differently by mass and density.
as an object sinks deeper the gradient of the walls of the material becomes greater than 1, this represents its gravitational attraction.
A spherical object with speed (direction is not important at this stage) thrown into this "gravity well" will "orbit moving about the walls of the well but resistance would eventually bring it to rest in the bottom.

Now... the only problems with this representation is that an object may be so light that it would not even sink, and also objects have resistance, plus it is only 2 dimensional.

And... although there is sufficient evidence to state black holes exist they are yet to be proven and what we see know are computer generated models, what we know as hawking radiation is mostly made of photons and neutrinos.

in this model gravitational field is determined by mass, if your matter has mass it should have gravity.
 
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