The primary purpose of this note is to provide an instructional summary of the state of the art regarding cyclic monotonicity and related notions. We will also present how these notions are tied to optimality in the optimal transport (or Monge-Kantorovich) problem, even though cyclic monotonicity is simply a property of a set and can be studied on its own merit.

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

Luigi De Pascale

Dip. di Matematica ed Informatica, Università degli Studi di Firenze, Firenze, Italy

luigi.depascale@unifi.it

Anna Kausamo

Dip. di Matematica ed Informatica, Università degli Studi di Firenze, Firenze, Italy

akausamo@gmail.com

Katarzyna Wyczesany

Dept. of Mathematical Sciences, Carnegie Mellon University, Pittsburgh, U.S.A.

kwycz@cmu.edu
  1. T. Abdellaoui, H. Henich: Sur la distance de deux lois dans le cas vectoriel, C. R. Acad. Sci. Ser. 1, Math. 319/4 (1994) 397–400.Google Scholar
  2. L. Ambrosio, N. Gigli: A user’s guide to optimal transport, in: Modelling and Optimisation of Flows on Networks, B. Piccoli et al. (eds.), Cetraro 2009, Lecture Notes in Mathematics 2062, Springer, Berlin (2013) 1–155.https://doi.org/10.1007/978-3-642-32160-3_1Google Scholar
  3. L. Ambrosio, N. Gigli, G. Savaré: Gradient Flows: in Metric Spaces and in the Space of Probability Measures, Springer, Cham (2005).Google Scholar
  4. L. Ambrosio, A. Pratelli: Existence and stability results in the L1 theory of optimal transportation, in: Optimal Transportation and Applications, L. A. Caffarelli et al. (eds.), Martina Franca 2001, Lecture Notes in Mathematics 1813, Springer, Berlin (2003) 123–160.https://doi.org/10.1007/978-3-540-44857-0_5Google Scholar
  5. S. Artstein-Avidan, S. Sadovsky, K. Wyczesany: A Rockafellar-type theorem for nontraditional costs, Adv. Math. 395 (2022), art. no. 108157.https://doi.org/10.1016/j.aim.2021.108157Google Scholar
  6. S. Artstein-Avidan, S. Sadovsky, K. Wyczesany: Optimal measure transportation with respect to non-traditional costs, Calc. Var. Partial Diff. Equations 62/1 (2023), art. no. 35, 39 p.https://doi.org/10.1007/s00526-022-02362-wGoogle Scholar
  7. S. Bartz, H. Bauschke, H. Phan, X. Wang: Multi-marginal maximal monotonicity and convex analysis, Math. Programming 185/1 (2021) 385–408.https://doi.org/10.1007/s10107-019-01433-9Google Scholar
  8. S. Bartz, H. Bauschke, X. Wang: A class of multi-marginal c-cyclically monotone sets with explicit c-splitting potentials, J. Math. Analysis Appl. 461/1 (2018) 333–348.https://doi.org/10.1016/j.jmaa.2018.01.015Google Scholar
  9. M. Beiglböck, M. Goldstern, G. Maresch, W. Schachermayer: Optimal and better transport plans, J. Funct. Analysis 256/6 (2009) 1907–1927.https://doi.org/10.1016/j.jfa.2009.01.013Google Scholar
  10. J. Bertrand: Prescription of Gauss curvature using optimal mass transport, Geom. Dedicata 183(1) (2016) 81–99.https://doi.org/10.1007/s10711-016-0147-3Google Scholar
  11. J. Bertrand, A. Pratelli, M. Puel: Kantorovich potentials and continuity of total cost for relativistic cost functions, J. Math. Pures Appl. 110 (2018) 93–122.https://doi.org/10.1016/j.matpur.2017.09.005Google Scholar
  12. J. Bertrand, M. Puel: The optimal mass transport problem for relativistic costs, Calc. Var. Partial Diff. Equations 46/1-2 (2013) 353–374.https://doi.org/10.1007/s00526-011-0485-9Google Scholar
  13. S. Bianchini, L. Caravenna: On the extremality, uniqueness and optimality of transference plans, Bull. Inst. Math., Acad. Sin. (N.S.) 4/4 (2009) 353–454.Google Scholar
  14. S. Bianchini, L. Caravenna: On optimality of c-cyclically monotone transference plans, C. R. Math. Acad. Sci. Paris 348/11-12 (2010) 613–618.https://doi.org/10.1016/j.crma.2010.03.022Google Scholar
  15. Y. Brenier: Polar factorization and monotone rearrangement of vector-valued functions, Comm. Pure Appl. Math. 44/4 (1991) 375–417.https://doi.org/10.1002/cpa.3160440402Google Scholar
  16. Y. Brenier: Extended Monge-Kantorovich theory, in: Optimal Transportation and Applications, L. A. Caffarelli et al. (eds.), Martina Franca 2001, Lecture Notes in Mathematics 1813, Springer, Berlin (2003) 91–121.https://doi.org/10.1007/978-3-540-44857-0_4Google Scholar
  17. L. Caffarelli: The regularity of mappings with a convex potential, J. Amer. Math. Soc. 5/1 (1992) 99–104.https://doi.org/10.1090/S0894-0347-1992-1124980-8Google Scholar
  18. T. Champion, L. De Pascale, P. Juutinen: The ∞-Wasserstein distance: local solutions and existence of optimal transport maps, SIAM J. Math. Analysis 40/1 (2008) 1–20.https://doi.org/10.1137/07069938XGoogle Scholar
  19. M. Cuturi, G. Peyré: Computational optimal transport: With applications to data science, Found. Trends Mach. Learning 11/5-6 (2019) 355–607.https://doi.org/10.1561/2200000073Google Scholar
  20. L. De Pascale, A. Kausamo: Sufficiency of c-cyclical monotonicity in a class of multimarginal optimal transport problems, arXiv: 2212.08375 (2022).Google Scholar
  21. W. Gangbo, R. J. McCann: The geometry of optimal transportation, Acta Math. 177/2 (1996) 113–161.https://doi.org/10.1007/BF02392620Google Scholar
  22. W. Gangbo, V. Oliker: Existence of optimal maps in the reflector-type problems, ESAIM Control, Optim. Calc. Var. 13/1 (2007) 93–106.https://doi.org/10.1051/cocv:2006017Google Scholar
  23. C. Griessler: c-cyclical monotonicity as a sufficient criterion for optimality in the multimarginal Monge-Kantorovich problem, Proc. Amer. Math. Soc. 146/11 (2018) 4735–4740.https://doi.org/10.1090/proc/14129Google Scholar
  24. H. Jylhä: The l∞ -optimal transport: infinite cyclical monotonicity and the existence of optimal transport maps, Calc. Var. Partial Diff. Equations 52 (2015) 303–326.https://doi.org/10.1007/s00526-014-0713-1Google Scholar
  25. Y.-H. Kim, B. Pass: A general condition for Monge solutions in the multi-marginal optimal transport problem, SIAM J. Math. Analysis 46/2 (2014) 1538–1550.https://doi.org/10.1137/130930443Google Scholar
  26. M. Knott, C. Smith: On Hoeffding-Fréchet bounds and cyclic monotone relations, J. Multivar. Analysis 40/2 (1992) 328–334.https://doi.org/10.1016/0047-259X(92)90029-FGoogle Scholar
  27. R. J. McCann: Existence and uniqueness of monotone measure-preserving maps, Duke Math. J. 80 (1995) 309–323.https://doi.org/10.1215/S0012-7094-95-08013-2Google Scholar
  28. G. Minty: On the monotonicity of the gradient of a convex function, Pacific J. Math. 14/1 (1964) 243–247.https://doi.org/10.2140/pjm.1964.14.243Google Scholar
  29. J.-J. Moreau: Convex functionals, Seminaire Jean Leray 2 (1966) 1–108.Google Scholar
  30. M. Petrache: Cyclically monotone non-optimal n-marginal transport plans and Smirnov-type decompositions for n-flows, ESAIM Control Optim. Calc. Var. 26 (2020), art. no. 120, 11 p.https://doi.org/10.1051/cocv/2020050Google Scholar
  31. A. Pratelli: On the sufficiency of c-cyclical monotonicity for optimality of transport plans, Math. Zeitschrift 258/3 (2008) 677–690.https://doi.org/10.1007/s00209-007-0191-7Google Scholar
  32. Yu. V. Prokhorov: Convergence of random processes and limit theorems in probability theory, Theory Probab. Appl. 1/2 (1956) 157–214.https://doi.org/10.1137/1101016Google Scholar
  33. J.-C. Rochet: A necessary and sufficient condition for rationalizability in a quasilinear context, J. Math. Economics 16/2 (1987) 191–200.https://doi.org/10.1016/0304-4068(87)90007-3Google Scholar
  34. R. T. Rockafellar: Characterization of the subdifferentials of convex functions, Pacific J. Math. 17/3 (1966) 497–510.https://doi.org/10.2140/pjm.1966.17.497Google Scholar
  35. R. T. Rockafellar: Convex Analysis, Princeton Landmarks in Mathematics, Princeton University Press, Princeton (1997).Google Scholar
  36. R. T. Rockafellar: Convex Analysis, Princeton Landmarks in Mathematics, Princeton University Press, Princeton (2015).Google Scholar
  37. R. T. Rockafellar, R. J-B Wets: Variational Analysis, Grundlehren der mathematischen Wissenschaften 317, Springer, Berlin (2009).Google Scholar
  38. L. Rüschendorf: On c-optimal random variables, Statistics Probab. Letters 27/3 (1996) 267–270.https://doi.org/10.1016/0167-7152(95)00078-XGoogle Scholar
  39. F. Santambrogio: Optimal Transport for Applied Mathematicians, Calculus of Variations, PDEs and Modelling, Progress in Nonlinear Differential Equations and their Applications 87, Birkhäuser, Cham (2015).https://doi.org/10.1007/978-3-319-20828-2Google Scholar
  40. W. Schachermayer, J. Teichmann: Characterization of optimal transport plans for the Monge-Kantorovich problem, Proc. Amer. Math. Soc. 137/2 (2009) 519–529.https://doi.org/10.1090/S0002-9939-08-09419-7Google Scholar
  41. C. Villani: Optimal Transport: Old and New, Grundlehren der mathematischen Wissenschaften 338, Springer, Berlin (2008).https://doi.org/10.1007/978-3-540-71050-9Google Scholar
  42. C. Villani: Topics in Optimal Transportation, Graduate Studies in Mathematics 58, American Mathematical Society, Providence (2021).Google Scholar
  43. K. Wyczesany: Topics in High-Dimensional Geometry and Optimal Transport, PhD thesis, University of Cambridge, Cambridge (2021).Google Scholar

L. De Pascale, A. Kausamo, K. Wyczesany. “60 Years of Cyclic Monotonicity: a Survey.” Journal of Convex Analysis 32 (2025), No. 2, 399–430. https://doi.org/10.68381/jca32020