A comparison theorem for the isoperimetric profile under curve-shortening flow

Curvature Bound for Curve Shortening Flow via Distance Comparison and a Direct Proof of Grayson’s Theorem

Abstract. A new isoperimetric estimate is proved for embedded closed curves evolving by curve shortening flow, normalized to have total length 2π. The estimate bounds the length of any chord from below in terms of the arc length between its endpoints and elapsed time. Applying the estimate to short segments we deduce directly that the maximum curvature decays exponentially to 1. This gives a se...

Curve Shortening and Grayson’s Theorem

In this chapter and the next we discuss the curve shortening flow (CSF). A number of important techniques in the field of geometric flows exhibit themselves in the curve shortening flow in an elegant and less technical way. The CSF was proposed in 1956 by Mullins to model the motion of idealized grain boundaries. In 1978 Brakke studied the mean curvature flow, of which the CSF is the 1-dimensio...

An isoperimetric comparison theorem

Results of Triangles Under Discrete Curve Shortening Flow

In this paper, we analyze the results of triangles under discrete curve shortening flow, specifically isosceles triangles with top angles greater than π3 , and scalene triangles. By considering the location of the three vertices of the triangle after some small time , we use the definition of the derivative to calculate a system of differential equations involving parameters that can describe t...

Curve Shortening Flow in a Riemannian Manifold

In this paper, we systemally study the long time behavior of the curve shortening flow in a closed or non-compact complete locally Riemannian symmetric manifold. Assume that we have a global flow. Then we can exhibit a a limit for the global behavior of the flow. In particular, we show the following results. 1). Let M be a compact locally symmetric space. If the curve shortening flow exists for...