Given a Riemannian manifold together with a group of isometries, we discuss MCF of the orbits and some applications: eg, finding minimal orbits. We then specialize to Lagrangian orbits in Kaehler manifolds. In particular, in the Kaehler-Einstein case we find a relation between MCF and moment maps which, for example, proves that the minimal Lagrangian orbits are isolated.

We compare different methods used for non-perturbative calculations in strongly interacting fermionic systems. Mean field theory shows a basic ambiguity related to the possibility to perform Fierz transformations. The results depend strongly on an unphysical parameter which reflects the choice of the mean field. Renormalization group equations in a partially bosonized setting can overcome this ...

We prove a local existence and uniqueness result of crystalline mean curvature flow starting from a compact convex admissible set in R . This theorem can handle the facet breaking/bending phenomena, and can be generalized to any anisotropic mean curvature flow. The method provides also a generalized geometric evolution starting from any compact convex set, existing up to the extinction time, sa...

We study the mean curvature flow of complete space-like submanifolds in pseudo-Euclidean space with bounded Gauss image, as well as that of complete submanifolds in Euclidean space with convex Gauss image. By using the confinable property of the Gauss image under the mean curvature flow we prove the long time existence results in both cases. We also study the asymptotic behavior of these soluti...

In this paper we study the generalized mean curvature flow of sets in the sub-Riemannian geometry of Carnot groups. We extend to our context the level sets method and the weak (viscosity) solutions introduced in the Euclidean setting in [29] and [14]. We establish two special cases of the comparison principle, existence, uniqueness and basic geometric properties of the flow.

In this note we prove the backwards uniqueness of the mean curvature flow in codimension one case. More precisely,let Ft, e Ft : M → M n+1 be two complete solutions of the mean curvature flow on M×[0, T ] with bounded second fundamental form in a complete ambient manifold with bounded geometry. Suppose FT = e FT , then Ft = e Ft on M n × [0, T ]. This is an analog of a recent result of Kotschwa...

We introduce a regularization method for mean curvature flow of a submanifold of arbitrary codimension in the Euclidean space, through higher order equations. We prove that the regularized problems converge to the mean curvature flow for all times before the first singularity.

We prove the mean curvature flow of a spacelike graph in (Σ1 ×Σ2,g1 −g2) of a map f : Σ1 → Σ2 from a closed Riemannian manifold (Σ1,g1) with Ricci1 > 0 to a complete Riemannian manifold (Σ2,g2) with bounded curvature tensor and derivatives, and with K2 ≤ K1, remains a spacelike graph, exists for all time, and converges to a slice at infinity. We also show, with no need of the assumption K2 ≤ K1...

Cash flows are often modeled using the random geometric growth model (geometric Brownian motion). One of the reasons for using this model is that it is simple to implement and it is a reasonable approximation to random growth cash flows such as stock prices. For this model the volatility of the cash flow grows multiplicatively over time. This multiplicative characteristic is shared by the usual...