Tác giả: Martin R. Bridson

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The purpose of this book is to describe the global properties of complete simply- connected spaces that are non-positively curved in the sense of A. D. Alexandrov and to examine the structure of grou …

The authors prove that if $F$ is a finitely generated free group and $/phi$ is an automorphism of $F$ then $F/rtimes_/phi/mathbb Z$ satisfies a quadratic isoperimetric inequality. The authors’ proof …