Abstract
We survey recent work of Burghelea, Malta and both authors on the topology of critical sets of nonlinear ordinary differential operators. For a generic nonlinearity f, the critical set of the first order nonlinear operator F 1(u)(t) = u′(t) + f(u(t)) acting on the Sobolev space H 1p of periodic functions is either empty or ambient diffeomorphic to a hyperplane. For the second order operator F 2(u)(t) = −u″(t) + f(u(t)) on H 2D (Dirichlet boundary conditions), the critical set is ambient diffeomorphic to a union of isolated parallel hyperplanes. For second order operators on H 2p , the critical set is not a Hilbert manifold but is still contractible and admits a normal form. The third order case is topologically far more complicated.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
A. Ambrosetti and G. Prodi, On the inversion of some differentiable maps between Banach spaces with singularities, Ann. Mat. Pura Appl. 93 (1972), 231–246.
M. Berger and E. Podolak, On the solutions of a nonlinear Dirichlet problem, Ind. Univ. Math. J. 24 (1975), 837–846.
H. Bueno and C. Tomei, Critical sets of nonlinear Sturm-Liouville operators of Ambrosetti-Prodi type, Nonlinearity 15 (2002), 1073–1077.
D. Burghelea, N. Saldanha and C. Tomei, Results on infinite-dimensional topology and applications to the structure of the critical set of nonlinear Sturm-Liouville operators, J. Diff. Eq 188 (2003), 569–590.
D. Burghelea, N. Saldanha and C. Tomei, The topology of the monodromy map of the second order ODE, arXiv:math.CA/0507120.
D. Burghelea, N. Saldanha and C. Tomei, The geometry of the critical set of periodic Sturm-Liouville operators, in preparation.
V. Cafagna and F. Donati, Un résultat global de multiplicité pour un probléme différentiel non linéaire du premier ordre, C. R. Acad. Sci. Paris Sér. 300 (1985), 523–526.
M. Calanchi and B. Ruf, On the number of closed solutions for polynomial ODE’s and a special case of Hilbert’s 16th problem, Advances in Diff. Equ. 7 (2002), 197–216.
P.T. Church, E.N. Dancer and J.G. Timourian, The structure of a nonlinear elliptic operator, Trans. Amer. Math. Soc. 338 no. 1 (1993), 1–42.
A. Lins Neto, On the number of solutions of the equation dx/dt = Σ nj =0 aj(t)x j, 0 ≤ t ≤ 1, for which x(0) = x(1), Inventiones Math. 59 (1980), 67–76.
J.A. Little, Nondegenerate homotopies of curves on the unit 2-sphere, J. Differential Geometry 4 (1970), 339–348.
H.P. McKean and J.C. Scovel, Geometry of some simple nonlinear differential operators, Ann. Sc. Norm. Sup. Pisa Cl. Sci. (4) 13 (1986), 299–346.
I. Malta, N.C. Saldanha and C. Tomei, The numerical inversion of functions from the plane to the plane, Math. Comp. 65 (1996), 1531–1552.
I. Malta, N.C. Saldanha and C. Tomei, Morin singularities and global geometry in a class of ordinary differential equations, Top. Meth. in Nonlinear Anal. 10 no. 1 (1997), 137–169.
I. Malta, N.C. Saldanha and C. Tomei, Regular level sets of averages of Nemytskiĭ operators are contractible, J. Func. Anal. 143 (1997), 461–469.
B. Morin, Formes canoniques de singularités d’une application différentiable, C. R. Acad. Sc. Paris 260 (1965), 5662–5665 and 6503–6506.
B. Ruf, Singularity theory and bifurcation phenomena in differential equations, Topological Nonlinear Analysis II, Progr. in Nonlin. Diff. Equ. and Appl. 27, eds. M. Matzeu, A. Vignoli, Birkhäuser, 1997.
N. Saldanha, Homotopy and cohomology of spaces of locally convex curves in the sphere, arXiv:math.GT/0407410.
N. Saldanha and C. Tomei, Functions from \( \mathbb{R}^2 \) to \( \mathbb{R}^2 \): a study in nonlinearity, arXiv:math.NA/0209097.
B. Shapiro and B. Khesin, Homotopy classification of nondegenerate quasiperiodic curves on the 2-sphere, Publ. Inst. Math. (Beograd) 66(80) (1999), 127–156.
B. Shapiro and M. Shapiro, On the number of connected components of nondegenerate curves on \( \mathbb{S} \) n, Bull. of the AMS 25 (1991), 75–79.
M. Shapiro, Topology of the space of nondegenerate curves, Math. USSR 57 (1993), 106–126.
H. Whitney, On singularities of mappings of Euclidean spaces I. Mappings of the plane into the plane, Ann. Math. 62 (1955), 374–410.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Additional information
Dedicated to Djairo Figueiredo, with affection and admiration.
Rights and permissions
Copyright information
© 2005 Birkhäuser Verlag Basel/Switzerland
About this chapter
Cite this chapter
Saldanha, N.C., Tomei, C. (2005). The Topology of Critical Sets of Some Ordinary Differential Operators. In: Cazenave, T., et al. Contributions to Nonlinear Analysis. Progress in Nonlinear Differential Equations and Their Applications, vol 66. Birkhäuser Basel. https://doi.org/10.1007/3-7643-7401-2_33
Download citation
DOI: https://doi.org/10.1007/3-7643-7401-2_33
Publisher Name: Birkhäuser Basel
Print ISBN: 978-3-7643-7149-4
Online ISBN: 978-3-7643-7401-3
eBook Packages: Mathematics and StatisticsMathematics and Statistics (R0)