Christoffel symbols evaluate to zero

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Zach Elgood

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May 26, 2016, 2:23:37 PM5/26/16
to xAct Tensor Computer Algebra
I recently started up a new notebook on xact and have come across an issue which I am unsure how to solve. Doing a very simple Schwarzschild calculation, I get that all the Christoffel symbols are zero, which is clearly incorrect. 
Lorentz-violation.nb

Leo Stein

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May 26, 2016, 3:03:03 PM5/26/16
to Zach Elgood, xAct Tensor Computer Algebra
Dear Zach,

Note that r and theta are scalar functions on the manifold, and thus need square brackets [] after them when appearing in calculations.

Leo

On Thu, May 26, 2016 at 11:19 AM, Zach Elgood <zache...@gmail.com> wrote:
I recently started up a new notebook on xact and have come across an issue which I am unsure how to solve. Doing a very simple Schwarzschild calculation, I get that all the Christoffel symbols are zero, which is clearly incorrect. 

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Lorentz-violation.nb

Zach Elgood

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May 27, 2016, 2:30:33 PM5/27/16
to xAct Tensor Computer Algebra, zache...@gmail.com
Thank you, that was a very silly mistake on my part. Also, when the Christoffel symbols are calculated, they appear to be of the first kind. Is there a way to calculate those of the second kind. Obviously you can simply multiply by the metric, but I was wondering if there was a build in method, as I can only seem to find those of the first kind.
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