We study a sufficient condition under which a maximal monotone operator T ⁣:X⇉X∗T\colon X\tos X^* admits a unique maximal monotone extension to the bidual T~ ⁣:X∗∗⇉X∗\widetilde T\colon X^{**}\tos X^*. We will prove that for non-linear operators this condition is equivalent to uniqueness of the extension. The central tool in our approach is the S\mathcal{S}-function defined and studied previously by R. S. Burachik and B. F. Svaiter ["Maximal monotone operators, convex functions and a special family of enlargements", Set-Valued Analysis 10 (2002) 297–316]. For a generic operator, this function is the supremum of all convex lower semicontinuous functions which are majorized by the duality product in the graph of the operator. We also prove in this work that if the graph of a maximal monotone operator is convex, then this graph is an affine linear subspace.

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Maicon Marques Alves

Instituto de Matemática Pura e Aplicada, Estrada Dona Castorina 110, Jardim Botânico, Rio de Janeiro, RJ 22460-320, Brazil

maicon@impa.br

Benar Fux Svaiter

Instituto de Matemática Pura e Aplicada, Estrada Dona Castorina 110, Jardim Botânico, Rio de Janeiro, RJ 22460-320, Brazil

benar@impa.br
  1. H. H. Bauschke, X. Wang, L. Yao: Monotone linear relations: maximality and Fitzpatrick functions, ArXiv:0805.4256v1 (May 2008).Google Scholar
  2. G. Birkhoff: Lattice Theory, 3rd Ed., Colloquium Publications 25, American Mathematical Society, Providence (1967).Google Scholar
  3. J. M. Borwein: Maximal monotonicity via convex analysis, J. Convex Analysis 13(3-4) (2006) 561–586.https://doi.org/10.68381/jca13045Google Scholar
  4. J. M. Borwein: Maximality of sums of two maximal monotone operators in general Banach space, Proc. Amer. Math. Soc. 135(12) (2007) 3917–3924.https://doi.org/10.1090/S0002-9939-07-08960-5Google Scholar
  5. R. S. Burachik, A. N. Iusem, B. F. Svaiter: Enlargement of monotone operators with applications to variational inequalities, Set-Valued Anal. 5(2) (1997) 159–180.https://doi.org/10.1023/A:1008615624787Google Scholar
  6. R. S. Burachik, B. F. Svaiter: ε-enlargements of maximal monotone operators in Banach spaces, Set-Valued Anal. 7(2) (1999) 117–132.https://doi.org/10.1023/A:1008730230603Google Scholar
  7. R. S. Burachik: Maximal monotone operators, convex functions and a special family of enlargements, in: International Workshop on Optimization and Control with Applications (Erice, July 2001), short talk.Google Scholar
  8. R. S. Burachik, B. F. Svaiter: Maximal monotone operators, convex functions and a special family of enlargements, Technical Report A094, IMPA, Rio de Janeiro (August 2001), available at http://www.preprint.impa.br/Shadows/SERIE_A/2001/94.html.Google Scholar
  9. R. S. Burachik, B. F. Svaiter: Maximal monotone operators, convex functions and a special family of enlargements, Set-Valued Anal. 10(4) (2002) 297–316.https://doi.org/10.1023/A:1020639314056Google Scholar
  10. R. S. Burachik, B. F. Svaiter: Maximal monotonicity, conjugation and the duality product, Proc. Amer. Math. Soc. 131(8) (2003) 2379–2383.https://doi.org/10.1090/S0002-9939-03-07053-9Google Scholar
  11. R. S. Burachik, A. N. Iusem: On non-enlargeable and fully enlargeable monotone operators, J. Convex Analysis 13(3–4) (2006) 603–622.https://doi.org/10.68381/jca13047Google Scholar
  12. R. Correa, P. Gajardo: Eigenvalues of set-valued operators in Banach spaces, Set-Valued Anal. 13(1) (2005) 1–19.https://doi.org/10.1007/s11228-004-2769-0Google Scholar
  13. S. Fitzpatrick: Representing monotone operators by convex functions, in: Workshop / Miniconference on Functional Analysis and Optimization (Canberra, 1988), Proc. Centre Math. Anal. Austral. Nat. Univ. 20, Austral. Nat. Univ., Canberra (1988) 59–65.Google Scholar
  14. J.-P. Gossez: Opérateurs monotones non linéaires dans les espaces de Banach non réflexifs, J. Math. Anal. Appl. 34 (1971) 371–395.https://doi.org/10.1016/0022-247X(71)90119-3Google Scholar
  15. J.-P. Gossez; On the range of a coercive maximal monotone operator in a nonreflexive Banach space, Proc. Amer. Math. Soc. 35 (1972) 88–92.https://doi.org/10.1090/S0002-9939-1972-0298492-7Google Scholar
  16. J.-P. Gossez: On a convexity property of the range of a maximal monotone operator, Proc. Amer. Math. Soc. 55(2) (1976) 359–360.https://doi.org/10.1090/S0002-9939-1976-0397485-2Google Scholar
  17. J.-P. Gossez: On the extensions to the bidual of a maximal monotone operator, Proc. Amer. Math. Soc. 62(1) 67–71 (1977).https://doi.org/10.1090/S0002-9939-1977-0428121-5Google Scholar
  18. T. T. Hue, J. J. Strodiot: Convergence analysis of a relaxed extragradient-proximal point algorithm application to variational inequalities, Optimization 54(2) (2005) 191–213.https://doi.org/10.1080/02331930512331331610Google Scholar
  19. A. Kaplan, R. Tichatschke: Bregman-like functions and proximal methods for variational problems with nonlinear constraints, Optimization 56(1–2) (2007) 253–265.https://doi.org/10.1080/02331930600809259Google Scholar
  20. P.-E. Maingé, A. Moudafi: A proximal method for maximal monotone operators via discretization of a first order dissipative dynamical system, J. Convex Analysis 14(4) (2007) 869–878.https://doi.org/10.68381/jca14049Google Scholar
  21. M. Marques Alves, B. F. Svaiter: Brøndsted-Rockafellar property and maximality of monotone operators representable by convex functions in non-reflexive Banach spaces, J. Convex Analysis 15(4) (2008) 693–706.https://doi.org/10.68381/jca15047Google Scholar
  22. J.-E. Martínez-Legaz, B. F. Svaiter: Monotone operators representable by l.s.c. convex functions, Set-Valued Anal. 13(1) (2005) 21–46.https://doi.org/10.1007/s11228-004-4170-4Google Scholar
  23. J.-P. Penot: The relevance of convex analysis for the study of monotonicity, Nonlinear Anal., Theory Methods Appl. 58A(7–8) (2004) 855–871.https://doi.org/10.1016/j.na.2004.05.018Google Scholar
  24. J.-P. Penot: The use of nonsmooth analysis and of duality methods for the study of hamilton-jacobi equations, in: International Workshop on Optimization and Control with Applications (Erice, July 2001), short talk.Google Scholar
  25. S. Simons: The range of a monotone operator, J. Math. Anal. Appl. 199(1) (1996) 176–201.https://doi.org/10.1006/jmaa.1996.0135Google Scholar
  26. M. V. Solodov, B. F. Svaiter: A hybrid approximate extragradient-proximal point algorithm using the enlargement of a maximal monotone operator, Set-Valued Anal. 7(4) (1999) 323–345.https://doi.org/10.1023/A:1008777829180Google Scholar
  27. M. V. Solodov, B. F. Svaiter: A unified framework for some inexact proximal point algorithms, Numer. Funct. Anal. Optimization 22(7–8) (2001) 1013–1035.https://doi.org/10.1081/NFA-100108320Google Scholar
  28. B. F. Svaiter: A family of enlargements of maximal monotone operators, Set-Valued Anal. 8(4) (2000) 311–328.https://doi.org/10.1023/A:1026555124541Google Scholar
  29. B. F. Svaiter: Fixed points in the family of convex representations of a maximal monotone operator, Proc. Amer. Math. Soc. 131(12) (2003) 3851–3859.https://doi.org/10.1090/S0002-9939-03-07083-7Google Scholar
  30. D. Torralba: Convergence Épigraphique et Changements d’Échelle en Analyse Variationnelle et Optimisation, Ph.D. Thesis, Universite Montpellier II, Montpellier (1996).Google Scholar
  31. M. D. Voisei: The sum and chain rules for maximal monotone operators, Set-Valued Anal., submitted (2006).https://doi.org/10.1007/s11228-007-0042-zGoogle Scholar

M. Marques Alves, B. F. Svaiter. “Maximal Monotone Operators with a Unique Extension to the Bidual.” Journal of Convex Analysis 16 (2009), No. 2, 409–421. https://doi.org/10.68381/jca16022