Quantitative conditions of rectifiability for varifolds

Abstract: Our purpose is to state quantitative conditions ensuring the rectifiability of a $d$--varifold $V$ obtained as the limit of a sequence of $d$--varifolds $(V_i)_i$ which need not to be rectifiable. More specifically, we introduce a sequence $\left\lbrace \mathcal{E}_i \right\rbrace_i$ of functionals defined on $d$--varifolds, such that if $\displaystyle \sup_i \mathcal{E}_i (V_i) < +\infty$ and $V_i$ satisfies a uniform density estimate at some scale $\beta_i$, then $V = \lim_i V_i$ is $d$--rectifiable. \noindent The main motivation of this work is to set up a theoretical framework where curves, surfaces, or even more general $d$--rectifiable sets minimizing geometrical functionals (like the length for curves or the area for surfaces), can be approximated by "discrete" objects (volumetric approximations, pixelizations, point clouds etc.) minimizing some suitable "discrete" functionals.