We discuss various formulas for the subdifferential of the sum of lower semicontinuous convex functions given in terms of certain topological closure operations on the sum of the subdifferentials of each function. We show how the accuracy of the formulas expressed by the closure operations can be improved when additional assumptions on the family of functions are available.

Contact details are reproduced from the original publication and may be historical.

Florence Jules

Dép. de Mathématiques, Université des Antilles et de la Guyane, 97159 Pointe à Pitre, Guadeloupe, France

fjules@univ-ag.fr

Marc Lassonde

Dép. des Mathématiques, Université des Antilles et de la Guyane, 97159 Pointe à Pitre, Guadeloupe, France

lassonde@univ-ag.fr
  1. H. Attouch, J.-B. Baillon, M. Théra: Variational sum of maximal monotone operator, J. Convex Anal. 1(1) (1994) 1–29.https://doi.org/10.68381/jca01001Google Scholar
  2. H. Attouch, H. Brezis: Duality for the sum of convex functions, in: General Banach Spaces, Aspects of Mathematics and its Applications, North-Holland Math. Library 34, North-Holland, Amsterdam (1986) 125–133.https://doi.org/10.1016/S0924-6509(09)70252-1Google Scholar
  3. J. M. Borwein: Adjoint process duality, Math. Oper. Res. 8(3) (1983) 403–434.https://doi.org/10.1287/moor.8.3.403Google Scholar
  4. J. M. Borwein, S. Fitzpatrick, R. Girgenshon: Subdifferentials whose graphs are not norm × weak∗ closed, CECM Preprint 01:175 (2001).Google Scholar
  5. H. Brézis: Equations et inéquations non linéaires dans les espaces vectoriels en dualité, Ann. Inst. Fourier 18 (1968) 115–175.https://doi.org/10.5802/aif.280Google Scholar
  6. H. Brézis, L Nirenberg, G. Stampacchia: A remark on Ky Fan’s minimax principle, Boll. Un. Mat. Ital. 6(4) (1972) 293–300.Google Scholar
  7. F. E. Browder: Nonlinear operators and nonlinear equations of evolution in Banach spaces, in: Nonlinear Functional Analysis, Proc. Sympos. Pure Math., Vol. XVIII, Part 2, Chicago, Ill., 1968, Amer. Math. Soc., Providence, RI (1976) 1–308.Google Scholar
  8. M. Geoffroy, M. Lassonde: On a convergence of lower semicontinuous functions linked with the graph convergence of their subdifferentials, in: Constructive, Experimental and Nonlinear Analysis (Limoges, 1999), CMS Conf. Proc. 27, Amer. Math. Soc., Providence, RI (2000) 93–109.Google Scholar
  9. M. S. Gowda, M. Teboulle: A comparison of constraint qualifications in infinite-dimensional convex programming, SIAM J. Control Optim. 28(4) (1990) 925–935.https://doi.org/10.1137/0328051Google Scholar
  10. J.-B. Hiriart-Urruty, R. Phelps: Subdifferential calculus, using ε-subdifferentials, J. Funct. Anal. 118(1) (1993) 154–166.https://doi.org/10.1006/jfan.1993.1141Google Scholar
  11. F. Jules: Sur la somme de sous-différentiels de fonctions semi-continues inférieurement, Ph. D. Thesis, Univ. Antilles-Guyane (2000).Google Scholar
  12. F. Jules, M. Lassonde: Sommes approchées de sous-différentiels, Partie I : Théorie, Prépubl. no. 00/03, Dept Math. Info., Univ. Antilles-Guyane (2000).Google Scholar
  13. F. Jules, M. Lassonde: Sommes approchées de sous-différentiels, Partie II : Spécialisations, Prépubl. no. 00/04, Dept Math. Info., Univ. Antilles-Guyane (2000).Google Scholar
  14. M. Lassonde: First order rules in nonsmooth constrained optimization, Nonlinear Anal. 44(8), Ser. A: Theory Methods (2001) 1031–1056.https://doi.org/10.1016/S0362-546X(99)00321-1Google Scholar
  15. J.-L. Lions: Quelques Méthodes de Résolution des Problèmes aux Limites non Linéaires, Dunod, Gauthier-Villars, Paris, XX (1969).Google Scholar
  16. J.-P. Penot: Subdifferential calculus without qualification assumptions, J. Convex Anal. 3(2) (1996) 207–219.https://doi.org/10.68381/jca03014Google Scholar
  17. S. M. Robinson: Regularity and stability for convex multivalued functions, Math. Oper. Res. 1(2) (1976) 130–143.https://doi.org/10.1287/moor.1.2.130Google Scholar
  18. R. T. Rockafellar: Conjugate duality and optimization, in: CBMS Regional Conference Series in Applied Mathematics 16, SIAM VI, Philadelphia, Pa. (1974).https://doi.org/10.1137/1.9781611970524.ch1Google Scholar
  19. L. Thibault: A generalized sequential formula for subdifferentials of sums of convex functions defined on Banach spaces, in: Recent Developments in Optimization (Dijon, 1994), Lecture Notes in Econ. and Math. Systems 429, Springer, Berlin (1995) 340–345.https://doi.org/10.1007/978-3-642-46823-0_25Google Scholar
  20. L. Thibault: Sequential convex subdifferential calculus and sequential Lagrange multipliers, SIAM J. Control Optim. 35(4) (1997) 1434–1444.https://doi.org/10.1137/S0363012995287714Google Scholar
  21. L. Thibault: Limiting convex subdifferential calculus with applications to integration and maximal monotonicity of subdifferential, in: Constructive, Experimental and Nonlinear Analysis (Limoges, 1999), CMS Conf. Proc. 27, Amer. Math. Soc., Providence, RI (2000) 279–289.Google Scholar

F. Jules, M. Lassonde. “Formulas for Subdifferentials of Sums of Convex Functions.” Journal of Convex Analysis 9 (2002), No. 2, 519–533. https://doi.org/10.68381/jca09030