BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250714T203803EDT-59298nhvxF@132.216.98.100 DTSTAMP:20250715T003803Z DESCRIPTION:Title:New results on the real Jacobian conjecture\n\n \n\nAbstr act:\n\nThe real Jacobian conjecture said:\n If F=(f\,g):R→R be a polynomia l map such that det DF (x) is different from zero for all x ∈ R 2 \, then F is injective.\n \n This conjecture had a negative answer by Pinchuk in 199 4. Now several authors look for adding an additional assumption to the fac t that det(DF(x)) is different from zero for all x ∈ R2\, in order that th e conjecture holds. The next two theorems are proved using qualitative the ory of the ordinary differential equations in the plane. More precisely in the talk we will show how the Poincaré compactification of polynomial vec tor fields\, and the Poincaré-Hopf Theorem are used for proving the next t wo results.\n \n Theorem 1. Let F=(f\,g):R2→R2 be a polynomial map such that det(DF(x)) is different from zero for all x ∈ R2. We assume that the degr ees of f and g are equal and that the higher homogeneous terms of the poly nomials f and g do not have real linear factors in common\, then F is inje ctive.\n \n Theorem 2. Let F=(f\,g):R2→R2 be a polynomial map such that det( DF(x)) is different from zero for all x ∈ R2 and F(0\,0) = (0\,0). If the higher homogeneous terms of the polynomials f f_x + g g_x and f f_y + g g_ y do not have real linear factors in common\, then F is injective.\n DTSTART:20190910T190000Z DTEND:20190910T200000Z LOCATION:Room 1214\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Jaume Llibre (Universitat Autònoma de Barcelona) URL:/mathstat/channels/event/jaume-llibre-universitat- autonoma-de-barcelona-300200 END:VEVENT END:VCALENDAR