What Unique Insights Does Wald Offer on Teaching General Relativity?

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Wald's insights on teaching General Relativity (GR) suggest that undergraduate courses can effectively focus on physical applications without delving deeply into tensors or the Einstein field equations. He advocates for using metrics derived from Lagrange's equations to explore topics like black holes and cosmology, allowing for a more engaging learning experience. For graduate courses, Wald acknowledges the necessity of teaching tensors but admits there is no satisfactory method to do so, often finding it a low point in his teaching. He presents two approaches: one that emphasizes manifolds and tensors as multilinear maps, which is more fundamental but time-consuming, and another that is coordinate-based, allowing for quicker coverage but lacking depth in certain areas. Ultimately, Wald's approach aims to balance the teaching of GR with practical applications while addressing the challenges of conveying complex concepts.
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http://arxiv.org/abs/gr-qc/0511074 was entertaining to read. I like the conlcution:
Therefore, if the Earth were flat, we could explain terrestrial
physics by saying: bodies fall downward because
there is a white wall 3 × 1015 meters away sitting over-
head in the heavens which is pushing off them. Moreover,
for example, we could test General Relativity by sending a
light signal upwards to the sky, and receiving it six months later.
:biggrin:
 
Spin_Network said:
That has an interesting angle on GR.
http://arxiv.org/abs/hep-th/0511131
What you think it,s only a short paper?
http://arxiv.org/abs/gr-qc/0511074

Interesting papers.

this paper is agreat resource for relativity learning:http://arxiv.org/abs/gr-qc/0511073

This resource letter by R. M. Wald for teachers of general relativity is very interesting. Wald has come around to the point of view that it's OK to teach undergraduate general relativity courses that don't cover tensors or the Einstein fild equation. Undergraduate courses should concentrate on mining (via, e.g., Lagrange's equations) given (not derived as solutions to Einstein's equation) metrics for physical information. This way, much more time can be spent on quantitative aspects of interesting topics like black holes and cosmology.

Wald: "The philosophy on teaching general relativity to undergraduates expounded in this resource letter is adopted directly from the approach taken directly from Hartle in this (Hartle's) text."

For grad courses, Wald says that tensors must be taught, but that there is no satisfactory way of doing this.

Wald: "In 30 years of teaching general relativity at the graduate level, I have not found a satisfactory solution to this problem, and I have always found the discussion of tensors to be the 'low point' of this course,"

Wald say that there are 2 main options: 1) manifolds, and tensors as multilinear maps; 2) tensors strictly form a coordinate-based point of view.

1) is more fundamental, but requires more time, which leads to rushed presentations of physical applications of GR. 2) can be covered in half the time as 1), allowing for more leisurely and detailed presentations of physicall applications, but is not sufficient for treating things like global methods and singularity theorems.

Regards,
George
 
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