Why is the sign in Einstein's equation's RHS often presented differently?

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Fast question :I noticed that often the EFE are presented without the minus sign in the source term, (G=kT instead of G=-kT) does that have some reason behind or is it just plain sloppiness?
 
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Hi, TrickyDicky.

There are two ways of contraction defined in getting Ricci tensor from Rieman curvature tensor, i.e. contraction of first two indexes and contraction of the first and last indexes. Since Rieman tensor is antisymmetric, two ways are different only in sign.

Regards.
 
Ok, thanks.
 
http://equatorfreq.wordpress.com/2010/08/13/signs-in-einsteins-equation/" is a more detailed explanation. I really find all these different conventions confusing.
 
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