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Plan for PURE Math 2012 Seminar
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{\it Week 3}
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\item{} Monday:  Distance coordinates and configuration spaces
\item{} Tuesday:  Central configurations in
the $3$- and $n$-body problems
\item{} Wednesday: 
\item{} Thursday: 
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\centerline{PURE Math 2012 - Seminar}
\centerline{Week 3 Discussions - Background on Central Configurations}
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{\it Day 1: Distance coordinates and configuration spaces }
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{\it Background}
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We have seen in lecture that one way to describe configurations of $n$
points $p_1,\ldots, p_n$ in a Euclidean space up to Euclidean motions 
(translations and rotations) is to introduce the mutual distances 
$r_{ij} = \|p_i - p_j\|$ for $1 \le i < j\le n$ as {\it coordinates}.   
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