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arXiv · 1805.04796

Two-numbers and their applications - A survey

Bang-Yen Chen
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Abstract

The notion of two-numbers of connected Riemannian manifolds was introduced about 35 years ago in [Un invariant geometrique riemannien, C. R. Acad. Sci. Paris Math. 295 (1982), 389--391] by B.-Y. Chen and T. Nagano. Later, two-numbers have been studied by a number of mathematicians and it was then proved that two-numbers related closely with several important areas in mathematics. The main purpose of this article is to survey on two-numbers and their applications. At the end of this survey, we present several open problems and conjectures on two-numbers.

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Bang-Yen Chen. 2018-05-12. Two-numbers and their applications - A survey. https://arxiv.org/abs/1805.04796

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