announcement of GRwiki

I am pleased to announce the creation of GRwiki. The URL is

    http://grwiki.physics.ncsu.edu/

 From the "About" page:

GRwiki is a repository of basic definitions and formulas for 
gravitational physics. It is meant to serve as a high-level tool for 
active GR researchers, not a place to learn the theory. This site began 
as a transcription of handwritten notes, including definitions and 
derivations, that I collected over the years and kept in a file drawer. 
These notes have been an indispensable resource for my research. If I 
ever needed the definition of the Lie derivative of a weight -2 
covariant vector density, I knew where I could find it. The problem with 
a file drawer full of notes is that it's not very portable. I wanted to 
have access to
these results from my office, home, and on the road. Hence this wiki was 
born.

Please use this site with care. My goal is to create a site with as few 
errors as possible, but there are no guarantees. You should not trust 
any result posted on GRwiki unless you have verified it for yourself.

You are also welcome to contribute to GRwiki. Please give careful 
thought to any additions or changes you might wish to make. Currently 
any registered user is allowed to edit GRwiki pages.

David Brown
NCSU
March 2008