Matrix Formalism of GR: Good References for Writing Equations

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SUMMARY

This discussion focuses on the search for references that explain the equations of General Relativity (GR) using matrix notation. The user highlights the transformation of the covariant derivative and the metric tensor into matrix form, specifically mentioning the Hermitian nature of the metric matrix (g). A suggestion is made to explore the book "Exploring Black Holes," which offers a simplified approach to GR, reminiscent of MTW's "Gravitation." However, the discussion also emphasizes the limitations of matrix notation for representing higher-rank tensors, particularly the Riemann curvature tensor, which requires a more complex data structure.

PREREQUISITES
  • Understanding of General Relativity (GR) principles
  • Familiarity with matrix algebra and Hermitian matrices
  • Knowledge of covariant derivatives and tensor calculus
  • Basic concepts of rank 2 and rank 4 tensors
NEXT STEPS
  • Research the book "Exploring Black Holes" for insights on GR in matrix form
  • Study the Bianchi identities and their implications for the Riemann curvature tensor
  • Learn about tensor representation in different dimensions and data structures
  • Investigate the differences between matrix notation and traditional tensor notation in GR
USEFUL FOR

Students and researchers in theoretical physics, particularly those studying General Relativity, as well as mathematicians interested in the application of matrix notation to complex tensor equations.

thehangedman
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Are there any good references out there for writing the equations of GR in matrix format? For example:

ds^2 = g_mn dx_m dx_n -> ds^2 = dx+ g dx

where the matrix version of g_mn (g) would be hermitian, dx+ is the conjugate...

covariant derivative:

Y_n||m = dY_n/dx_m - {n, km} Y_k -> Y||m = dY/dx_m - G_m Y

in matrix format:

dg/dx_m + G_m g + g G+_m = 0 is the vanishing covariant derivative of the metric.

This is just a different way to write the same mathematics. It seams it would be easier to work with, but I can't find any good references for it. Hasn't someone else done this already? I'm just looking for something that gives the original GR back, no new theories, just new notation...
 
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I've seen one, but I can't locate it. I think it was aimed at electrical engineers, if I recall correctly. "Exploring black holes" might work, I don't know, I haven't read the whole thing, just some of the free downloads. Several chapters of this book are available on the internet. Much of the approach is very reminiscent of MTW's "Gravitation", without the high-level math. So it might not be quite what you asked for, but parts of it are free - and I'd check it out. Take a look at

http://www.eftaylor.com/general.html

However, there are good reasons for the serious student to not use matrix notation and to learn tensors. Rank 2 tensors can easily be represented in matrix form, so they aren't the issue. The problem is representing rank 4 tensors, such as the Riemann curvature tensor. I suppose you *could* think of a rank 4 as a general linear map from one matrix to another. This requires not a 2-d array, but a 4-d data structure. For space-time that's 4x4x4x4 = 256 numbers, which however are not all independent in the case of the Riemann, which must obey some identies (the Bianchi identites).
 

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