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Is there an error in this contracted calculation involving the Riemann and Ricci tensors?

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Jay R. Yablon

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Oct 19, 2009, 2:15:28 AM10/19/09
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I have attempted to obtain a contracted version of the relationship:

R^a_buv A_a = [&;_u, &;_v]A_b (2)

which defines the Riemann tensor. The calculation is in the one-page
file

http://jayryablon.files.wordpress.com/2009/10/can-you-find-the-error-in-this-calculation.pdf

The contracted result I end up with is:

R_au A^a = [&;_a, &;u] A^a (2)

where R_au is the Ricci tensor, but the mixed symmetry and antisymmetry
strikes me funny. I would like to know if this is a correct
calculation, and if I am missing anything.

Thanks,

Jay
____________________________
Jay R. Yablon
Email: jya...@nycap.rr.com
co-moderator: sci.physics.foundations
Weblog: http://jayryablon.wordpress.com/
Web Site: http://home.roadrunner.com/~jry/FermionMass.htm

Oh No

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Oct 23, 2009, 8:38:57 AM10/23/09
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Thus spake Jay R. Yablon <jya...@nycap.rr.com>

> I have attempted to obtain a contracted version of the relationship:
>
>R^a_buv A_a = [&;_u, &;_v]A_b (2)
>
>which defines the Riemann tensor. The calculation is in the one-page
>file
>
>http://jayryablon.files.wordpress.com/2009/10/can-you-find-the-error-
>in-this-calculation.pdf
>
>The contracted result I end up with is:
>
>R_au A^a = [&;_a, &;u] A^a (2)
>
>where R_au is the Ricci tensor, but the mixed symmetry and antisymmetry
>strikes me funny. I would like to know if this is a correct
>calculation, and if I am missing anything.
>

I think the basic problem is that when you switch indices in R_mu_alpha
you correctly do not change sign, but then you seem to think this
enables you to do the same for the commutator. The bit you think follows
by considering R in isolation does not in fact follow.

Regards

--
Charles Francis
moderator sci.physics.foundations.
charles (dot) e (dot) h (dot) francis (at) googlemail.com (remove spaces and
braces)

http://www.rqgravity.net

Jay R. Yablon

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Oct 23, 2009, 11:08:34 AM10/23/09
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"Oh No" <No...@charlesfrancis.wanadoo.co.uk> wrote in message
news:x9x$LtAnVZ...@charlesfrancis.wanadoo.co.uk...
Charles, Please clarify: Bottom line, is:

R_au A^a = [&;_a, &;u] A^a (2)

a correct result, and if not, at what exact step is there a mistake?

Jay.

Oh No

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Oct 24, 2009, 4:33:18 AM10/24/09
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That looked right to me, depending possibly on sign conventions.

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