Abstract:
For arbitrary $(q_1,q_2)$-quasimetric space, it is proved that
there exists a function $f,$ such that $f$-triangle inequality
is more exact than any $(q_1,q_2)$-triangle inequality.
It is shown that this function $f$ is the least one
in the set of all concave continuous functions $g$
for which $g$-triangle inequality hold.
The work is partially supported by the Russian Foundation for Basic Research (projects no. 18-01-00106_a, 19-01-00080_a). The results of Section 3 are due to the second author who was supported by the Russian Science Foundation (project no. 17-11-01168).
Received: 24.01.2019
Bibliographic databases:
Document Type:
Article
UDC:517
Language: Russian
Citation:
Z. T. Zhukovskaya, S. E. Zhukovskiy, R. Sengupta, “On exact triangle inequalities in $(q_1,q_2)$-quasimetric spaces”, Russian Universities Reports. Mathematics, 24:125 (2019), 33–38
This publication is cited in the following 2 articles:
E. S. Zhukovskiy, “Geometric progressions in distance spaces; applications to fixed points and coincidence points”, Sb. Math., 214:2 (2023), 246–272
T. V. Zhukovskaya, V. Merchela, “Ob ustoichivosti i nepreryvnoi zavisimosti ot parametra mnozhestva tochek sovpadeniya dvukh otobrazhenii, deistvuyuschikh v prostranstvo s rasstoyaniem”, Vestnik rossiiskikh universitetov. Matematika, 27:139 (2022), 247–260