Non-rotational and rotational metric tensors

In summary: In that case, the off-diagonal terms would contribute to the Einstein tensor metric element functions, but they would not contribute to the stress-energy tensor metric element functions.
  • #1
Orion1
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General Relativity...

Non-rotational spherically symmetric body of isotropic perfect fluid Einstein tensor metric element functions:
[tex]g_{\mu \nu} = \left( \begin{array}{ccccc} \; & dt & dr & d \theta & d\phi \\ dt & g_{tt} & 0 & 0 & 0 \\ dr & 0 & g_{rr} & 0 & 0 \\ d\theta & 0 & 0 & g_{\theta \theta} & 0 \\ d\phi & 0 & 0 & 0 & g_{\phi \phi} \end{array} \right) \; \; \; \; \; \; J = 0[/tex]

Non-rotational spherically symmetric body of isotropic perfect fluid Stress-Energy tensor metric element functions:
[tex]T_{\mu \nu} = \left( \begin{array}{ccccc} \; & dt & dr & d \theta & d\phi \\ dt & T_{tt} & 0 & 0 & 0 \\ dr & 0 & T_{rr} & 0 & 0 \\ d\theta & 0 & 0 & T_{\theta \theta} & 0 \\ d\phi & 0 & 0 & 0 & T_{\phi \phi} \end{array} \right) \; \; \; \; \; \; J = 0[/tex]

If the metric has rotation [itex](J \neq 0)[/itex] and the Einstein tensor metric element functions become non-zero for [itex]g_{t \phi}[/itex], do the Stress-Energy tensors also become non-zero for the corresponding Stress-Energy tensors [itex]T_{t \phi}[/itex]?

Rotational spherically symmetric body of isotropic perfect fluid Einstein tensor metric element functions:
[tex]g_{\mu \nu} = \left( \begin{array}{ccccc} \; & dt & dr & d \theta & d\phi \\ dt & g_{tt} & 0 & 0 & g_{t \phi} \\ dr & 0 & g_{rr} & 0 & 0 \\ d\theta & 0 & 0 & g_{\theta \theta} & 0 \\ d\phi & g_{t \phi} & 0 & 0 & g_{\phi \phi} \end{array} \right) \; \; \; \; \; \; J \neq 0[/tex]

Rotational spherically symmetric body of isotropic perfect fluid Stress-Energy tensor metric element functions:
[tex]T_{\mu \nu} = \left( \begin{array}{ccccc} \; & dt & dr & d \theta & d\phi \\ dt & T_{tt} & 0 & 0 & T_{t \phi} \\ dr & 0 & T_{rr} & 0 & 0 \\ d\theta & 0 & 0 & T_{\theta \theta} & 0 \\ d\phi & T_{t \phi} & 0 & 0 & T_{\phi \phi} \end{array} \right) \; \; \; \; \; \; J \neq 0[/tex]

Reference:
http://en.wikipedia.org/wiki/General_relativity#Einstein.27s_equations - General Relativity and Einstein's equations
http://en.wikipedia.org/wiki/Energy_conditions#Perfect_fluids - Energy Conditions of perfect fluids
 
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  • #2
The Einstein Field Equation does not relate the metric tensor to the stress-energy tensor. It relates the Einstein tensor to the stress-energy tensor. The Wikipedia page describes (briefly) what the Einstein tensor is.
 
  • #3
I could not parse your post well enough to give you a good answer, OP, but it seems, like Peter is interpreting, that you think there is a direct relationship between the non-zero members of the metric tensor with the non-zero members of the stress-energy tensor. This is very false, since, for example, in a Schwarzschild space-time all members of the stress-energy tensor are 0 everywhere (except at the singularity) and yet the metric tensor is non-zero.
 
  • #4
Also, it is possible to get off-diagonal terms in the Einstein tensor even if the metric tensor is diagonal.
 
  • #5


In General Relativity, the Einstein's field equations relate the curvature of spacetime to the distribution of matter and energy in the universe. The metric tensor is a mathematical tool used to describe the curvature of spacetime and is influenced by the distribution of matter and energy. In the case of a non-rotational spherically symmetric body of isotropic perfect fluid, the metric tensor and the stress-energy tensor are both diagonal and have zero values for off-diagonal elements, indicating no rotation.

However, if the metric has rotation, the off-diagonal elements become non-zero (J \neq 0) and this affects both the Einstein tensor and the Stress-Energy tensor. In this case, the Einstein tensor metric element functions g_{t\phi} become non-zero, indicating the presence of rotation in the spacetime. This in turn affects the corresponding Stress-Energy tensor metric element functions T_{t\phi}, which also become non-zero.

This is because the presence of rotation in the metric affects the distribution of matter and energy, which is described by the Stress-Energy tensor. Therefore, the Stress-Energy tensor also reflects the rotation in the spacetime.

In summary, the presence of rotation in the metric tensor affects both the Einstein tensor and the Stress-Energy tensor, and the corresponding metric element functions become non-zero. This is in accordance with the energy conditions of perfect fluids, which state that rotation can influence the distribution of energy and matter in the universe.
 

Related to Non-rotational and rotational metric tensors

1. What is the difference between non-rotational and rotational metric tensors?

Non-rotational metric tensors are symmetric tensors that describe the distance between two points in space without considering any rotation. Rotational metric tensors, on the other hand, take into account the effect of rotation on the distance between two points.

2. How are non-rotational and rotational metric tensors used in physics?

Non-rotational metric tensors are used in static situations where there is no rotation, such as in the study of electromagnetism. Rotational metric tensors are used in dynamic situations where rotation is present, such as in the study of fluid dynamics.

3. Can non-rotational and rotational metric tensors be combined?

Yes, it is possible to combine non-rotational and rotational metric tensors to create a mixed metric tensor. This allows for the study of situations where both static and dynamic effects are present.

4. How do non-rotational and rotational metric tensors relate to the concept of curvature?

Non-rotational metric tensors describe the intrinsic curvature of a space, while rotational metric tensors describe the extrinsic curvature caused by the presence of rotation. In general relativity, both types of tensors are used to describe the overall curvature of spacetime.

5. Are there real-world applications of non-rotational and rotational metric tensors?

Yes, these tensors are used in a variety of fields such as general relativity, electromagnetism, and fluid dynamics to describe the geometry of space and the effects of rotation. They are also used in computer graphics and computer vision for image processing and 3D reconstruction.

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