Faraday Tensor Conflicts: MTW vs. Wikipedia

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SUMMARY

The discussion centers on the discrepancies between the Faraday Tensor representations in the book "Gravitation" by Misner, Thorne, and Wheeler (MTW) and Wikipedia. Specifically, MTW presents the first line of the Faraday Tensor with a negative electrical field, while Wikipedia shows it with a positive electrical field. This conflict is attributed to differing sign conventions in relativity, particularly the metric signature and the ordering of indices. The conversation emphasizes the importance of understanding these conventions to accurately interpret the physics described by the Faraday Tensor.

PREREQUISITES
  • Understanding of the Faraday Tensor in electromagnetism
  • Familiarity with general relativity and metric signatures
  • Knowledge of covariant derivatives and index notation
  • Awareness of the Misner, Thorne, and Wheeler (MTW) textbook
NEXT STEPS
  • Research the various sign conventions in general relativity
  • Study the definition and properties of the Faraday Tensor
  • Examine the differences in index notation and their implications
  • Review the relevant sections in MTW for a comprehensive understanding of the topic
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Physicists, students of general relativity, and anyone interested in the nuances of electromagnetism and tensor calculus.

Cesarth
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Hello, I've found that the Faraday Tensor with both indeces down has in the first line, in MTW Gravitation book (pg 74, eq 3.7), minus the electrical field, while in Wikipedia we find that it is plus the electrical field.
Which one is right?
Does it depend on the signature of the metric?
 
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Unfortunately, there are numerous sign conventions in relativity.

The signature sign convention is one: [itex]+---[/itex] , [itex]-+++[/itex] (using the "0" convention for the time coordinate)
...so there is also the ordering of indices: is the time coordinate "0" or "4"?

There is also the definition of the Faraday tensor in terms of how covariant derivatives are notated... [itex]\nabla_{[a} A_{b]}[/itex]? [itex]A_{[b;a]}[/itex]?
Which index is used to form the electric field? [itex]u^{a}F_{ab}[/itex]? [itex]u^{b}F_{ab}[/itex]?

In the end, all sources should be describing the same physics... so one might look there to unravel the relationships among the conventions.
 
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If I do not misremember, there should be a table of different sign conventions and their relative results listed in MTW. I might have confused it with some other book though.
 

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