Si intende presentare, almeno in parte, l'imponente intreccio di idee, tecniche e acquisizioni concettuali che si è sviluppato intorno alla congettura di Poincaré, dalla sua formulazione agli inizi del secolo scorso fino alla soluzione data da Grisha Perelman agli inizi del nuovo millennio, portando a compimento il programma basato sullo studio del flusso di Ricci di metriche riemanniane su una data 3-varietà, delineato e sviluppato da Richard Hamilton dagli anni '80. Pur nei limiti e nelle possibilità di un articolo di rassegna, si è voluto presentare in modo matematicamente compiuto almeno alcune delle nozioni ed idee cruciali, a partire dalla formulazione stessa della congettura, disponendo soltanto di nozioni di base di algebra lineare, geometria e calcolo differenziale negli spazi euclidei , che si suppongono familiari al lettore. Ne risulterà probabilmente una lettura "impegnativa", non necessariamente "ricreativa", che però, almeno nelle intenzioni degli autori, dovrebbe ripagare il lettore con un'immagine piuttosto fedele di questi formidabili processi intellettuali, individuali e collettivi, che compongono una delle pagine più belle e profonde della storia della matematica.
Our aim is to present, at least partially, the great twine of ideas, techniques and concepts developed around the Poincaré conjecture, from its formulation at the beginning of last century to its solution due to Grisha Perelman at the beginning of the new millennium, completing the program based on the Ricci flow of Riemannian metrics on a 3-manifold, outlined and developed by Richard Hamilton since the '80s. In the limits and possibilities of a review paper, we wanted to present in a mathematically satisfactory way at least some of the crucial notions and ideas, starting from the precise formulation of the conjecture, using only basic concepts of linear algebra, geometry and differential calculus in the Euclidean space , that should be familiar to the reader. The result is possibly a "demanding" reading, not necessarily "recreational", but which, in our intentions, should reward the reader with a quite faithful image of these extraordinary intellectual achievements, individual and collective, composing one of the greatest and deepest pages of the history of mathematics.
@article{RUMI_2017_1_2_3_245_0, author = {Riccardo Benedetti and Carlo Mantegazza}, title = {La Congettura di Poincar\'e e il Flusso di Ricci}, journal = {Matematica, Cultura e Societ\`a. Rivista dell'Unione Matematica Italiana}, volume = {2}, year = {2017}, pages = {245-289}, mrnumber = {3753845}, language = {it}, url = {http://dml.mathdoc.fr/item/RUMI_2017_1_2_3_245_0} }
Benedetti, Riccardo; Mantegazza, Carlo. La Congettura di Poincaré e il Flusso di Ricci. Matematica, Cultura e Società. Rivista dell'Unione Matematica Italiana, Tome 2 (2017) pp. 245-289. http://gdmltest.u-ga.fr/item/RUMI_2017_1_2_3_245_0/
[1] An example of a simply connected surface bounding a region which is not simply connected, Proc. Nat. Acad. Sci. USA10 (1924), no. 1, 8-10.
,[2] | MR 1219310 | Zbl 0768.51018
and , Lectures on hyperbolic geometry, Universitext, Springer-Verlag, Berlin, 1992.[3] Conjecture de Poincaré: la preuve de R. Hamilton et G. Perelman, Gazette des Mathématiciens106 (2005), 7-35. | MR 3087240
,[4] 13, European Mathematical Society (EMS), Zürich, 2010. | MR 2683385 | Zbl 1244.57003
, , , , and , Geometrisation of 3-manifolds, EMS Tracts in Mathematics, vol.[5] Convergence of the Yamabe flow for arbitrary initial energy, J. Diff. Geom.69 (2005), no. 2, 217-278. | MR 2168505 | Zbl 1085.53028
,[6] A complete proof of the Poincaré and geometrization conjectures - application of the Hamilton-Perelman theory of the Ricci flow, Asian J. Math. 10 (2006), no. 2, 165-492. | MR 2233789 | Zbl 1200.53057
and ,[7] A note on uniformization of Riemann surfaces by Ricci flow, Proc. Amer. Math. Soc.134 (2006), no. 11, 3391-3393 (electronic). | MR 2231924 | Zbl 1113.53042
, , and ,[8] Width and finite extinction time of Ricci flow, Geom. Topol. 12 (2008), no. 5, 2537-2586. | MR 2460871 | Zbl 1161.53352
and ,[9] An application of gauge theory to four-dimensional topology, J. Differential Geom.18 (1983), no. 2, 279-315. | MR 710056 | Zbl 0507.57010
,[10] 57, Birkhäuser Boston Inc., Boston, MA, 2004. | MR 2024995
, Regularity theory for mean curvature flow, Progress in Nonlinear Differential Equations and their Applications,[11] Harmonic mappings of Riemannian manifolds, Amer. J. Math. 86 (1964), 109-160. | MR 164306 | Zbl 0122.40102
and ,[12] The topology of four-dimensional manifolds, J. Differential Geom.17 (1982), no. 3, 357-453. | MR 679066 | Zbl 0528.57011
,[13] Foliations and the topology of 3-manifolds, Bull. Amer. Math. Soc. (N.S.) 8 (1983), no. 1, 77-80. | MR 682826 | Zbl 0539.57013
,[14] An isoperimetric inequality with applications to curve shortening, Duke Math. J.50 (1983), no. 4, 1225-1229. | MR 726325 | Zbl 0534.52008
,[15] Curve shortening makes convex curves circular, Invent. Math.76 (1984), 357-364. | MR 742856 | Zbl 0542.53004
,[16] The heat equation shrinking convex plane curves, J. Diff. Geom. 23 (1986), 69-95. | MR 840401 | Zbl 0621.53001
and ,[17] | MR 1083149
, , and , Riemannian geometry, Springer-Verlag, 1990.[18] The heat equation shrinks embedded plane curves to round points, J. Diff. Geom.26 (1987), 285-314. | MR 906392 | Zbl 0667.53001
,[19] 62, Birkhäuser Boston, Inc., Boston, MA, 1986, I. Du côté de chez Rohlin. II. Le côté de Casson. [I. Rokhlin's way. II. Casson's way]. | MR 900243 | Zbl 0597.57001
and (eds.), À la recherche de la topologie perdue, Progress in Mathematics, vol.[20] Three-manifolds with positive Ricci curvature, J. Diff. Geom.17 (1982), no. 2, 255-306. | MR 664497 | Zbl 0504.53034
,[21] Four-manifolds with positive curvature operator, J. Diff. Geom.24 (1986), no. 2, 153-179. | MR 862046 | Zbl 0628.53042
,[22] The Ricci flow on surfaces, Mathematics and general relativity (Santa Cruz, CA, 1986), Contemp. Math., vol. 71, Amer. Math. Soc., Providence, RI, 1988, pp. 237-262. | MR 954419
,[23] The formation of singularities in the Ricci flow, Surveys in differential geometry, Vol. II (Cambridge, MA, 1993), Int. Press, Cambridge, MA, 1995, pp. 7-136. | MR 1375255
,[24] Four-manifolds with positive isotropic curvature, Comm. Anal. Geom.5 (1997), no. 1, 1-92. | MR 1456308 | Zbl 0892.53018
,[25] 43, American Mathematical Society, Providence, R.I., 1980. | MR 565450 | Zbl 0433.57001
, Lectures on three-manifold topology, CBMS Regional Conference Series in Mathematics, vol.[26] 761, Springer, Berlin, 1979. | MR 551744 | Zbl 0412.57007
, Homotopy equivalences of 3-manifolds with boundaries, Lecture Notes in Mathematics, vol.[27] Groups of homotopy spheres. I, Ann. of Math. (2) 77 (1963), 504-537. | MR 148075 | Zbl 0115.40505
and ,[28] A calculus for framed links in , Invent. Math.45 (1978), no. 1, 35-56. | MR 467753 | Zbl 0377.55001
,[29] Notes on Perelman's papers, ArXiv Preprint Server - http://arxiv.org, 2006. | MR 2460872
and ,[30] Notes on Perelman's papers, Geom. Topol. 12 (2008), no. 5, 2587-2855. | MR 2460872 | Zbl 1204.53033
and ,[31] A representation of orientable combinatorial 3-manifolds, Ann. of Math. (2) 76 (1962), 531-540. | MR 151948 | Zbl 0106.37102
,[32] 290, Birkhäuser/SpringerBasel AG, Basel, 2011. | MR 2815949 | Zbl 1230.53002
, Lecture notes on mean curvature flow, Progress in Mathematics, vol.[33] On manifolds homeomorphic to the 7-sphere, Ann. of Math. (2) 64 (1956), 399-405. | MR 82103 | Zbl 0072.18402
,[34] A unique decomposition theorem for 3-manifolds, Amer. J. Math.84 (1962), 1-7. | MR 142125 | Zbl 0108.36501
,[35] | MR 190942 | Zbl 0161.20302
, Lectures on the h-cobordism theorem, Notes by L. Siebenmann and J. Sondow, Princeton University Press, Princeton, N.J., 1965.[36] | MR 226651 | Zbl 0136.20402
, Topology from the differentiable viewpoint, Based on notes by David W. Weaver, The University Press of Virginia, Charlottesville, Va., 1965.[37] | MR 488059 | Zbl 0349.57001
, Geometric topology in dimensions 2 and 3, Springer-Verlag, New York-Heidelberg, 1977, Graduate Texts in Mathematics, Vol. 47.[38] 44, Princeton University Press, Princeton, NJ, 1996. | MR 1367507 | Zbl 0846.57001
, The Seiberg-Witten equations and applications to the topology of smooth four-manifolds, Mathematical Notes, vol.[39] Ricci flow and the Poincaré conjecture, ArXiv Preprint Server - http://arxiv.org, 2006. | MR 2334563
and ,[40] 3, American Mathematical Society, Providence, RI; Clay Mathematics Institute, Cambridge, MA, 2007. | MR 2334563
and , Ricci flow and the Poincaré conjecture, Clay Mathematics Monographs, vol.[41] Completion of the proof of the geometrization conjecture, ArXiv Preprint Server - http://arxiv.org, 2008. | MR 3186136
and ,[42] 5, American Mathematical Society, Providence, RI; Clay Mathematics Institute, Cambridge, MA, 2014. | MR 3186136 | Zbl 1302.53001
and , The geometrization conjecture, Clay Mathematics Monographs, vol.[43] Canonical decompositions of 3-manifolds, Geom. Topol. 1 (1997), 21-40 (electronic). | MR 1469066 | Zbl 0886.57009
and ,[44] The engulfing theorem for topological manifolds, Ann. of Math. (2) 84 (1966), 555-571. | MR 203708 | Zbl 0166.19801
,[45] The entropy formula for the Ricci flow and its geometric applications, ArXiv Preprint Server http://arxiv.org, 2002. | Zbl 1130.53001
,[46] Finite extinction time for the solutions to the Ricci flow on certain three-manifolds, ArXiv Preprint Server - http://arxiv.org, 2003. | Zbl 1130.53003
,[47] Ricci flow with surgery on three-manifolds, ArXiv Preprint Server - http://arxiv.org, 2003. | Zbl 1130.53002
,[48] 171, Springer, New York, 2006. | MR 2243772
, Riemannian geometry, second ed., Graduate Texts in Mathematics, vol.[49] 69. | MR 350744 | Zbl 0254.57010
and , Introduction to piecewise-linear topology, Springer-Verlag, New York-Heidelberg, 1972, Ergebnisse der Mathematik und ihrer Grenzgebiete, Band[50] Convergence of the Yamabe flow for "large" energies, J. Reine Angew. Math. 562 (2003), 59-100. | MR 2011332 | Zbl 1079.53100
and ,[51] Generalized Poincaré's conjecture in dimensions greater than four, Ann. of Math. (2) 74 (1961), 391-406. | MR 137124 | Zbl 0099.39202
,[52] On the structure of manifolds, Amer. J. Math.84 (1962), 387-399. | MR 153022 | Zbl 0109.41103
,[53] Polyhedral homotopy-spheres, Bull. Amer. Math. Soc.66 (1960), 485-488. | MR 124905 | Zbl 0111.18901
,[54] Perelman's proof of the Poincaré conjecture: a nonlinear PDE perspective, ArXiv Preprint Server http://arxiv.org, 2006. | MR 2647628
,[55] Three-dimensional manifolds, Kleinian groups and hyperbolic geometry, Bull. Amer. Math. Soc. (N.S.)6 (1982), no. 3, 357-381. | MR 648524 | Zbl 0496.57005
,[56] 35, Princeton University Press, Princeton, NJ, 1997, Edited by . | MR 1435975 | Zbl 0873.57001
, Three-dimensional geometry and topology. Vol. 1, Princeton Mathematical Series, vol.[57] On irreducible 3-manifolds which are sufficiently large, Ann. of Math. (2) 87 (1968), 56-88. | MR 224099 | Zbl 0157.30603
,[58] Modifications and cobounding manifolds, Canad. J. Math.12 (1960), 503-528. | MR 125588 | Zbl 0108.36101
,[59] Evolution of curves and surfaces by mean curvature, Proceedings of the International Congress of Mathematicians, Vol. I (Beijing, 2002), 2002, pp. 525-538. | MR 1989203 | Zbl 1036.53045
,[60] A certain open manifold whose group is unity, Quart. J. Math. Oxford Ser.6 (1939), 268-279. | MR 174464 | Zbl 61.0607.01
,[61] Certain theorems about three-dimensional manifolds (I), Quart. J. Math. Oxford Ser. 5 (1939), 308-320. | MR 174464 | Zbl 0010.27504
,[62] Global existence and convergence of Yamabe flow, J. Diff. Geom.39 (1994), no. 1, 35-50. | MR 1258912 | Zbl 0846.53027
,[63] The Poincaré conjecture for , Topology of 3-manifolds and related topics (Proc. The Univ. of Georgia Institute, 1961), Prentice-Hall, Englewood Cliffs, N.J., 1962, pp. 198-204. | MR 140113
,