Hyperconvex Semi-metric Spaces
نویسندگان
چکیده
We examine the close analogy which exists between Helly graphs and hyperconvex metric spaces, and propose the hyperconvex semi-metric space as an unifying concept. Unlike the metric spaces, these semi-metric spaces have a rich theory in the discrete case. Apart from some new results on Helly graphs, the main results concern: fixed point property of contractible semi-metric spaces (for nonexpansive multifunctions); and the injectivity of hyperconvex semi-metric spaces.
منابع مشابه
Topology Proceedings
We examine the close analogy which exists between Helly graphs and hyperconvex metric spaces, and propose the hyperconvex semi-metric space as an unifying concept. Unlike the metric spaces, these semi-metric spaces have a rich theory in the discrete case. Apart from some new results on Helly graphs, the main results concern: fixed point property of contractible semi-metric spaces (for nonexpans...
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