

\subsection{\bf Decorrelation of}
\subsection{\bf Pseudorandom Numbers}
\begin{slide}
\begin{itemize}
\item Numerical Recipes has a program that removes any such problems.
Its algorithm is essentially as follows:

\begin{description}
\item{$\bullet$} Set up a list $R(1\ldots L)$ of $L$ random numbers.
\item{$\bullet$} Then choose randomly $j$ where $1\le j\le L$.
\item{$\bullet$} Set desired random number $= R(j)$. 
\item{$\bullet$} Replace $R(j)$ by a new random number.  
\end{description}

\item These correlations are particularly important in
accurate calculations of condensed matter phase transitions 

\begin{description}
\item{$\bullet$} as you are measuring correlations between local spins
and so these must have uncorrelated random generators.
\end{description}
\end{itemize}
\end{slide}

