The difference vectors for convex sets and a resolution of the geometry conjecture
Open Journal of Mathematical Optimization, Tome 2 (2021), article no. 5, 18 p.

The geometry conjecture, which was posed nearly a quarter of a century ago, states that the fixed point set of the composition of projectors onto nonempty closed convex sets in Hilbert space is actually equal to the intersection of certain translations of the underlying sets.

In this paper, we provide a complete resolution of the geometry conjecture. Our proof relies on monotone operator theory. We revisit previously known results and provide various illustrative examples. Comments on the numerical computation of the quantities involved are also presented.

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DOI : 10.5802/ojmo.7
Mots clés : Attouch–Théra duality, circular right shift operator, convex sets, cycle, fixed point set, monotone operator theory, projectors.
Alwadani, Salihah 1 ; Bauschke, Heinz H. 1 ; Revalski, Julian P. 2 ; Wang, Xianfu 1

1 Mathematics University of British Columbia Kelowna, B.C. V1V 1V7 Canada
2 Institute of Mathematics and Informatics Bulgarian Academy of Sciences Acad. G. Bonchev str., Block 8 1113 Sofia Bulgaria
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Alwadani, Salihah; Bauschke, Heinz H.; Revalski, Julian P.; Wang, Xianfu. The difference vectors for convex sets and a resolution of the geometry conjecture. Open Journal of Mathematical Optimization, Tome 2 (2021), article  no. 5, 18 p. doi : 10.5802/ojmo.7. http://www.numdam.org/articles/10.5802/ojmo.7/

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