# The Morse index of Free Boundary Minimal Hypersurfaces

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A free boundary minimal hypersurface in the unit Euclidean ball is a critical point of the area functional among all hypersurfaces with boundaries in the unit sphere, the boundary of the ball. While regularity and existence aspects of this subjecct have been extensively investigated, little is known about uniqueness. That motivates the study of the Morse index, which quantitatively measures the number of deformations decreasing the area to second order. Henceforth, A. Fraser and R. Schoen proposed a fundamental conjecture concerning surfaces with low indices. In this talk, we discuss recent developments including a joint work with Ari Stern, Detang Zhou, and Graham Smith.

# ALE Kahler Manifolds

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In recent years the scalar flat asymptotically locally Euclidean (ALE) Kahler manifolds attracted a lot of attention, and many examples were constructed. However, their classification is not understood, except for the case of ALE Ricci flat Kahler surfaces. In this talk, I will present a first step in this direction: the underlying complex structure of ALE Kahler manifolds is exposed to be a resolution of a deformation of an isolated quotient singularity. The talk is based on a joint work with Hans-Joachim Hein and Ioana Suvaina.

# Kahler-Ricci solitons on crepant resolutions of quotients of C^n

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By a gluing construction, we produce steady Kahler-Ricci solitons on equivariant crepant resolutions of C^n/G, where G is a finite subgroup of SU(n), generalizing Cao's construction of such a soliton on a resolution of C^n/Z_n. This is joint work with Olivier Biquard.

# Compactness and generic finiteness for free boundary minimal hypersurfaces

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Free boundary minimal hypersurfaces are critical points of the area functional in compact manifolds with boundary. In general, a free boundary minimal hypersurface may be improper, i.e., the interior of the hypersurface may touch the boundary of the ambient manifold. In this talk, we will present recent work on compactness and generic finiteness results for improper free boundary minimal hypersurfaces. This is joint work with Xin Zhou.