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arXiv · 1010.1863

Soul Theorem for 4-dimensional Topologically Regular Open Nonnegatively Curved Alexandrov Spaces

Jian Ge
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Abstract

In this paper, we study the topology of topologically regular 4-dimensional open non-negatively curved Alexandrov spaces. These spaces occur naturally as the blow-up limits of compact Riemannian manifolds with lower curvature bound. These manifolds have also been studied by Yamaguchi in his preprint [Yam2002]. Our main tools are gradient flows of semi-concave functions and critical point theory for distance functions, which have been used to study the 3-dimensional collapsing theory in the paper [CaoG2010]. The results of this paper will be used in our future studies of collapsing 4-manifolds, which will be discussed elsewhere.

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Jian Ge. 2010-10-09. Soul Theorem for 4-dimensional Topologically Regular Open Nonnegatively Curved Alexandrov Spaces. https://arxiv.org/abs/1010.1863

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