Can Matter Shape the Metric in Analog Models of Gravity?

In summary, analog models of gravity involve the influence of the metric on the motion of matter, and there are efforts to detect Hawking radiation in sonic black holes. However, in GR geometry and matter interact with each other. There are some analogue models in which the metric is shaped by matter, but none in which the equation for the metric follows the form of the Einstein equations. Additionally, gravity can be best described on a 2D plane with objects sinking deeper based on their mass and density, and resistance eventually bringing them to a stop. However, this model has limitations such as not accounting for very light objects and being only 2D. While black holes are yet to be proven, the concept of Hawking radiation mainly involves photons and
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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
 
  • #3
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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Related to Can Matter Shape the Metric in Analog Models of Gravity?

1. What are analog models of gravity?

Analog models of gravity are physical systems that mimic certain aspects of gravity, particularly the effects of space-time curvature, without actually involving gravitational forces. They are used to study and understand various aspects of general relativity and other theories of gravity.

2. How do analog models of gravity work?

Analog models of gravity work by using mathematical analogues of space-time and matter to represent the effects of gravity. These analogues can be physical systems such as fluids, crystals, or electromagnetic fields, or they can be mathematical models such as acoustic or optical systems.

3. What are the advantages of using analog models of gravity?

Analog models of gravity offer several advantages over numerical or analytical models. They provide a physical, hands-on way to study and visualize the effects of gravity, making it easier to understand complex concepts. They also allow for the exploration of extreme scenarios that are difficult to simulate in other ways.

4. What are the limitations of analog models of gravity?

Analog models of gravity cannot fully replicate the effects of gravity in all situations. They are limited by the properties of the physical or mathematical systems used, and may not accurately represent all aspects of gravity. They also cannot make precise predictions, but rather provide qualitative insights and conceptual understanding.

5. How are analog models of gravity used in scientific research?

Analog models of gravity are used in a variety of research areas, including cosmology, astrophysics, and high-energy physics. They are particularly useful for studying the early universe, black holes, and other extreme environments. They also provide a way to test and validate theoretical models of gravity and explore alternative theories.

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