Gromov hyperbolic John is quasihyperbolic John

讲座时间 Datetime: 2022年9月6日，星期二，15:45-16:45

地点 Venue: 腾讯线上会议：892-677-691

主持人 Host：邵国宽

报告人 Speaker: 周青山

单位 Affiliation: 佛山科技大学

报告摘要 Abstract:

In this talk, we introduce a concept of quasihyperbolic John spaces and provide a necessary and sufficient condition for a space to be quasihyperbolic John. Using this criteria, we exhibit a simple proof to show that a John space with a Gromov hyperbolic quasihyperbolization is quasihyperbolic John, quantitatively. Both bounded and unbounded cases are in our considerations.

This result provides a new approach to an elementary metric geometry question, formulated by Heinonen (Rev. Math. Iber., 1989), which has been studied by Gehring, Hag and Martio (Math. Scand., 1989). This is a recent work joint with Antti Rasila, Yaxiang Li, and Saminathan Ponnusamy.