On Kottman's constants in Banach spaces
Volume 92 / 2011
Banach Center Publications 92 (2011), 75-84 MSC: 46B04, 46B08, 46B20. DOI: 10.4064/bc92-0-5
This paper deals with a few, not widely known, aspects of Kottman's constant of a Banach space and its symmetric and finite variations. We will consider their behaviour under ultrapowers, relations with other parameters such as Whitley's or James' constant, and connection with the extension of $c_0$-valued Lipschitz maps.