Stress-energy tensor explicitly in terms of the metric tensor

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SUMMARY

The discussion focuses on rewriting the Einstein field equations, specifically the relationship between the Ricci curvature tensor $$R_{\mu\nu}$$ and the metric tensor $$g_{\mu\nu}$$. Participants recommend utilizing the equations $$R=g^{\mu\nu}R_{\mu\nu}$$ and $$R_{\mu\nu}=R^\lambda_{\mu\lambda\nu}$$ to express the Ricci tensor explicitly in terms of the metric. The conversation highlights the complexity of this task and suggests using computer algebra systems like Cadabra or Maxima to facilitate the calculations. The stress-energy tensor, represented as $$G_{\mu \nu} \equiv R_{\mu \nu} - \frac{1}{2} g_{\mu \nu} R$$, is also discussed in relation to the energy content of space.

PREREQUISITES
  • Understanding of Einstein field equations
  • Familiarity with Ricci curvature tensor and scalar curvature
  • Knowledge of Riemann curvature tensor and Christoffel symbols
  • Experience with computer algebra systems, specifically Cadabra or Maxima
NEXT STEPS
  • Research the explicit forms of the Riemann tensor in terms of Christoffel symbols
  • Explore the use of Cadabra for tensor calculations
  • Study the properties of the Einstein tensor and its applications
  • Investigate advanced topics in general relativity related to metric tensors
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The discussion is beneficial for theoretical physicists, mathematicians specializing in differential geometry, and researchers working on general relativity and gravitational theories.

CarlosMarti12
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I am trying to write the Einstein field equations
$$R_{\mu\nu}-\frac{1}{2}g_{\mu\nu} R=\frac{8\pi G}{c^4}T_{\mu\nu}$$
in such a way that the Ricci curvature tensor $$R_{\mu\nu}$$ and scalar curvature $$R$$ are replaced with an explicit expression involving the metric tensor $$g_{\mu\nu}$$ using the equations $$R=g^{\mu\nu}R_{\mu\nu}$$ (relating the scalar curvature to the trace of the Ricci curvature tensor) and $$R_{\mu\nu}=R^\lambda_{\mu\lambda\nu}$$ (relating the Ricci curvature tensor to the trace of the Riemann curvature tensor). Would anyone be willing to give recommendations on how to proceed, or already know the equation?
 
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Look up the standard expressions for the Riemann tensor in terms of the Christoffel symbols, and the Christoffel symbols in terms of the metric. It's going to be extremely messy. Consider using a computer algebra system for this; probably either Cadabra or Maxima could do it, and both are free and open source.
 
Stress-Energy tensor deals with the energy content of space. It's the Einstein tensor ##G_{\mu \nu} \equiv R_{\mu \nu} - \frac{1}{2} g_{\mu \nu} R## that you want to write in terms of the metric tensor. Anyway, as Ben said it's going to be extremely messy. See:
http://en.wikipedia.org/wiki/Einstein_tensor#Explicit_form
 

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