Covariant vs absolute derivative

AI Thread Summary
The discussion critiques the terminology used in the online text on differential geometry, specifically the incorrect labeling of the "derivative along the curve" as the "covariant derivative." Participants question whether others refer to DP/dtau as the covariant derivative of P and note the author's lack of clarity regarding lower indices in the context of total and partial covariant derivatives. The conversation highlights the existence of both covariant and contravariant differential geometries, as well as the associated connections and differentiations. References to external papers suggest ongoing research in contravariant connections and their applications. The discussion underscores the confusion surrounding terminology in the field.
pmb
In the online text on differential geometry

http://people.hofstra.edu/faculty/Stefan_Waner/RealWorld/pdfs/DiffGeom.pdf

The author calls the "derivative along the curve" (aka absolute derivative) the "covariant derivative" which is wrong.

It's on box 8.2 on page 59.

Does anyone else here refer to DP/dtau as the covariant derivative of P?

Pete
 
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Waner talks about total and partial covariant derivatives on pp. 59-61 and even covariant differentials on p. 62, with no regard to the business of setting new lower indices at all. There is a clue on p. 62, exercise set 8 #10(b), where a contravariant derivative is suggested but not exhibited. This yields some fruit under web search.

There seem to be covariant AND contravariant differential geometries, covariant AND contravariant affine connections, and covariant AND contravariant differentiations afoot. So, I suppose, that means partial and total derivatives of both kinds.

some found links -->

http://emis.bibl.cwi.nl/proceedings/Coimbra99/pdgloja.pdf
contravariant connections on poisson manifolds {Fernandes}

http://www.math.toronto.edu/henrique/keio.pdf
poisson vector bundles, contravariant connections and deformations {Bursztyn}

The name Izu Vaisman seems to be important.

{SIGH!}, so be the shifting sands of terminology!

Regards,
 
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