--- a/preamble.tex	Wed May 12 15:57:20 2010 -0700
+++ b/preamble.tex	Wed May 12 18:26:20 2010 -0500
@@ -2,7 +2,7 @@
 %!TEX root = blob1.tex
 %this ensures the arxiv doesn't try to start TeXing here.
 
-\usepackage{amsmath,amssymb,amsfonts}
+\usepackage{amsmath,amssymb,amsfonts,amsthm}
 \usepackage{ifpdf}
 
 %\ifpdf
@@ -11,6 +11,7 @@
 \usepackage[all,color]{xy}
 %\fi
 
+\usepackage[section]{placeins}
 \usepackage{leftidx}
 
 \SelectTips{cm}{}