- Orbital $\varphi$-regularity in coincidence and fixed point problems in metric spaces Tron Nguyen (nguyenhuutronqnu.edu.vn) Abstract: The purpose of the present paper is to establish some (approximate) fixed point or coincidence theorems for set-valued mappings defined on metric spaces under the so-called orbital \varphi-regularity of the considered mappings. This is a type of (\varphi,\gamma)-regularity of set-valued mappings which is weaker than orbital regularity. In turn, it is used in the previous work of the author [12] and before by Ioffe in the work [7] to ensure the existence of (approximate) fixed points or (approximate) coincidence points. Keywords: Orbital regularity, orbital pseudo-Lipschitz, orbital $\varphi$-regularity, (approximate) coincidence point,(µ,γ)-regularity Category 1: Nonlinear Optimization Citation: Download: [PDF]Entry Submitted: 12/28/2021Entry Accepted: 12/28/2021Entry Last Modified: 01/18/2022Modify/Update this entry Visitors Authors More about us Links Subscribe, Unsubscribe Digest Archive Search, Browse the Repository Submit Update Policies Coordinator's Board Classification Scheme Credits Give us feedback Optimization Journals, Sites, Societies Optimization Online is supported by the Mathematical Optmization Society.