\documentclass{ian-presentation} \usepackage[hidelinks]{hyperref} \usepackage{graphicx} \begin{document} \pagestyle{empty} \hbox{}\vfil \bf\Large \hfil Liquid crystals\par \smallskip \hfil and interacting dimers\par \vfil \large \hfil Ian Jauslin \normalsize \vfil \hfil\rm joint with {\bf Elliott H. Lieb}\par \vfil arXiv:{\tt \href{http://arxiv.org/abs/1709.05297}{1709.05297}}\hfill{\tt \href{http://ian.jauslin.org}{http://ian.jauslin.org}} \eject \setcounter{page}1 \pagestyle{plain} \title{Nematic liquid crystals} \vfil \hfil\includegraphics[width=6cm]{nematic.png} \vfil\eject \title{Nematic liquid crystals} \vfil \begin{itemize} \item {\bf Long range orientational order}: molecules tend to align, and maintain their alignment over macroscopic distances. \item {\bf No positional order}: the locations of the centers of the molecules are decorrelated. \end{itemize} \vfil\eject \title{Heilmann-Lieb model} \hfil[Heilmann, Lieb, 1979] \vfil \hfil\includegraphics[width=5cm]{interaction.pdf} \vfil\eject \title{Heilmann-Lieb model} \begin{itemize} \item Probability of a configuration (grand-canonical Gibbs distribution): $$ \mathrm{Prob}(\mathrm{conf})=\frac1\Xi z^{\#\mathrm{particles}}e^{J\ \#\mathrm{interactions}} $$ \begin{itemize} \item $\Xi$: partition function \item $z\geqslant 0$: activity \item $J\geqslant 0$: interaction strength \end{itemize} \item Regime $J\gg z\gg 1$. \end{itemize} \title{[Heilmann, Lieb, 1979]} \vfil \begin{itemize} \item {\it Theorem}: given $x,y\in\mathbb Z^2$, the probability that there is a horizontal dimer attached to $x$ and no horizontal dimer attached to $y$ tends to 0 as $J,z\to\infty$. ({\bf Orientational order}.) \item {\it Conjecture}: given to edges $e$ and $e'$, the probability of finding a dimer on $e$ and another on $e'$ is independent of $e$ and $e'$, up to a term that decays {\it exponentially} in $\mathrm{dist}(e,e')$. ({\bf No positional order}.) \end{itemize} \end{document}