Jean-Benoit Bost (Paris-Sud): "A-analytic curves in algebraic varieties over number fields and Arakelov positivity" Abstract: This talk will be devoted to some recent joint work with A. Chambert-Loir (Rennes). Let $X$ be a variety over a number field $K$, and let $\varphi: {\rm Spf} K[[T]] \rightarrow X$ be a formal curve which is $K_v$-analytic for all places $v$ of $K$. This talk will discuss various geometric conditions on the ``size" of $\varphi$ at various places $v$ which would imply either the rationality, or the algebraicity of $\varphi$. The case where $\varphi$ is an integral curve of an algebraic differential equation will be particularly considered.