Can the Ricci Scalar Depend on Spacetime Coordinates?

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SUMMARY

The Ricci Scalar can be computed using the metric tensor, which may or may not vary with spacetime coordinates. While the Ricci Scalar often returns as a constant, it can depend on the coordinate choice in specific cases, such as in general Lemaitre-Tolman-Bondi spacetimes where the Ricci tensor is proportional to the density of the dust configuration. This indicates that the Ricci Scalar's behavior is contingent upon the metric's characteristics and the spacetime configuration. Relevant literature includes works by C. W. Misner and D. H. Sharp, and S. Gonçalves.

PREREQUISITES
  • Understanding of the Ricci Scalar and its computation using the metric tensor
  • Familiarity with general relativity concepts, particularly Lemaitre-Tolman-Bondi spacetimes
  • Knowledge of tensor calculus and its application in physics
  • Experience with gravitational collapse theories and their mathematical formulations
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  • Study the implications of metric tensor variations in general relativity
  • Explore the properties of the Ricci tensor in different spacetime configurations
  • Investigate the relationship between density configurations and the Ricci Scalar in cosmological models
  • Review the works of C. W. Misner and D. H. Sharp, and S. Gonçalves for deeper insights
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Physicists, mathematicians, and students specializing in general relativity, cosmology, and gravitational theories will benefit from this discussion.

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Does it make sense for the Ricci Scalar to be a function of the spacetime coordinates?

In previous calculations I have carried out in the past, everytime the Ricci Scalar has been returned as a constant, rather than being explicitly dependent on the coordinates.

Thanks for any replies
 
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The value of the Ricci scalar can be computed using only the metric tensor, and the components of the metric tensor may or may not vary with spacetime coordinates. So a Ricci scalar might change as your coordinates change, but it might not. Due to all the contractions, the Ricci scalar might be constant even if the components of the metric change (as with the surface of a sphere), but this varies from case to case.
 
Thank you for your reply. My metric does indeed vary with the coordinates.
 
I think in the general Lemaitre-Tolman-Bondi spacetimes you will find that the Ricci tensor is proportional to the density of the dust configuration, and therefore you can tune it to whatever you like. Give 'em a go with GRtensor =]

* C. W. Misner and D. H. Sharp. Relativistic equations for adiabatic, spherically
symmetric gravitational collapse. Phys. Rev., 136:B571, October 1964.

* S. Gon¸calves. Shell crossing in generalized Tolman-Bondi spacetimes. Phys. Rev. D,
63(12):124017, June 2001.
 
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