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Perturbation Theory for PDEs

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Encyclopedia of Complexity and Systems Science
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Definition of the Subject

Perturbation theory for PDEs is a part of the qualitative theory of differential equations. One of the most effective methods of perturbationtheory is the normal form theory which consists of using coordinate transformations in order to describe the qualitative features of a given orgeneric equation. Classical normal form theory for ordinary differential equations has been used all along the last century in many different domains,leading to important results in pure mathematics, celestial mechanics, plasma physics, biology, solid state physics, chemistry and many otherfields.

The development of effective methods to understand the dynamics of partial differential equations is relevant in pure mathematics as well as in allthe fields in which partial differential equations play an important role. Fluidodynamics, oceanography, meteorology, quantum mechanics, andelectromagnetic theory are just a few examples of potential applications. More precisely, the normal...

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Abbreviations

Perturbation theory:

The study of a dynamical systems which is a perturbation of a system whose dynamics is known. Typically the unperturbed system is linear or integrable.

Normal form:

The normal form method consists of constructing a coordinate transformation which changes the equations of a dynamical system into new equations which are as simple as possible. In Hamiltonian systems the theory is particularly effective and typically leads to a very precise description of the dynamics.

Hamiltonian PDE:

A Hamiltonian PDE is a partial differential equation (abbreviated PDE) which is equivalent to the Hamilton equation of a suitable Hamiltonian function. Classical examples are the nonlinear wave equation , the Nonlinear Schrödinger equation , and the Kortweg–de Vries equation .

Resonance vs. Non-Resonance:

A frequency vector \( { \{\omega_k\}_{k=1}^n } \) is said to be non-resonant if its components are independent over the relative integers. On the contrary, if there exists a non-vanishing \( { K\in{\mathbb{Z}}^n } \) such that \( { \omega\cdot K=0 } \) the frequency vector is said to be resonant. Such a property plays a fundamental role in normal form theory. Non-resonance typically implies stability.

Actions:

The action of a harmonic oscillator is its energy divided by its frequency. It is usually denoted by I. The typical issue of normal form theory is that in nonresonant systems the actions remain approximatively unchanged for very long times. In resonant systems there are linear combinations of the actions with such properties.

Sobolev space:

Space of functions which have weak derivatives enjoying suitable integrability properties. Here we will use the spaces H s, \( { s\in {\mathbb{N}} } \) of the functions which are square integrable together with their first s weak derivatives.

Bibliography

  1. Arnold V (1984) Chapitres supplémentaires de la théorie des équationsdifférentielles ordinaires. Mir, Moscow

    Google Scholar 

  2. Bambusi D (1999) Nekhoroshev theorem for small amplitude solutions in nonlinearSchrödinger equation. Math Z 130:345–387

    MathSciNet  Google Scholar 

  3. Bambusi D (1999) On the Darbouxtheorem for weak symplectic manifolds. Proc Amer Math Soc 127(11):3383–3391

    MathSciNet  MATH  Google Scholar 

  4. Bambusi D (2003) Birkhoff normal form for some nonlinearPDEs. Comm Math Phys 234:253–283

    MathSciNet  ADS  MATH  Google Scholar 

  5. Bambusi D (2005) Galerkin averaging method and Poincarénormal form for some quasilinear PDEs. Ann Sc Norm Super Pisa Cl Sci 4(5):669–702

    MathSciNet  MATH  Google Scholar 

  6. Bambusi D (2008) A Birkhoff normal form theorem for somesemilinear PDEs. In: Craig W (ed) Hamiltonian dynamical systems and applications. Springer

    Google Scholar 

  7. Bambusi D, Carati A, Penati T (2007) On the relevance of boundary conditions forthe FPU paradox. Preprint Instit Lombardo Accad Sci Lett Rend A (to appear)

    Google Scholar 

  8. Bambusi D, Carati A, Ponno A (2002) The nonlinear Schrödinger equation asa resonant normal form. DCDS-B 2:109–128

    MathSciNet  MATH  Google Scholar 

  9. Bambusi D, Delort JM, Grébert B, Szeftel J (2007) Almost global existence forHamiltonian semi-linear Klein–Gordon equations with small Cauchy data on Zoll manifolds. Comm Pure Appl Math60(11):1665–1690

    Google Scholar 

  10. Bambusi D, Giorgilli A (1993) Exponential stability of states close toresonance in infinite-dimensional Hamiltonian systems. J Statist Phys 71(3–4):569–606

    MathSciNet  ADS  MATH  Google Scholar 

  11. Bambusi D, Grebert B (2003) Forme normale pour NLS en dimensionquelconque. Compt Rendu Acad Sci Paris 337:409–414

    MathSciNet  MATH  Google Scholar 

  12. Bambusi D, Grébert B (2006) Birkhoff normal form for partial differentialequations with tame modulus. Duke Math J 135(3):507–567

    Google Scholar 

  13. Bambusi D, Muraro D, Penati T (2008) Numerical studies on boundary effects on the FPU paradox. Phys Lett A 372(12):2039–2042

    MathSciNet  ADS  MATH  Google Scholar 

  14. Bambusi D, Nekhoroshev NN (1998) A property of exponential stability inthe nonlinear wave equation close to main linear mode. Phys D 122:73–104

    MathSciNet  MATH  Google Scholar 

  15. Bambusi D, Nekhoroshev NN (2002) Long time stability in perturbations ofcompletely resonant PDE's, Symmetry and perturbation theory. Acta Appl Math 70(1–3):1–22

    MathSciNet  MATH  Google Scholar 

  16. Bambusi D, Paleari S (2001) Families of periodic orbits for resonant PDE's. J Nonlinear Sci 11:69–87

    MathSciNet  ADS  MATH  Google Scholar 

  17. Bambusi D, Ponno A (2006) On metastability in FPU. Comm Math Phys264(2):539–561

    MathSciNet  ADS  MATH  Google Scholar 

  18. Bambusi D, Sacchetti A (2007) Exponential times in the one-dimensionalGross–Petaevskii equation with multiple well potential. Commun Math Phys 234(2):136

    Google Scholar 

  19. Berti M, Bolle P (2003) Periodic solutions of nonlinear wave equations withgeneral nonlinearities. Commun Math Phys 243:315–328

    MathSciNet  ADS  MATH  Google Scholar 

  20. Berti M, Bolle P (2006) Cantor families of periodic solutionsfor completely resonant nonlinear wave equations. Duke Math J 134(2):359–419

    MathSciNet  MATH  Google Scholar 

  21. Bourgain J (1996) Construction of approximative and almost-periodicsolutions of perturbed linear Schrödinger and wave equations. Geom Funct Anal 6:201–230

    MathSciNet  MATH  Google Scholar 

  22. Bourgain J (1996) On the growth in time of higherSobolev norms of smooth solutions of Hamiltonian PDE. Int Math Res Not 6:277–304

    Google Scholar 

  23. Bourgain J (1997) On growth in time of Sobolev norms of smooth solutions ofnonlinear Schrödinger equations in \( { R\sp D } \). J Anal Math 72:299–310

    MathSciNet  MATH  Google Scholar 

  24. Bourgain J (1998) Quasi-periodic solutions of Hamiltonian perturbationsof 2D linear Schrödinger equation. Ann Math 148:363–439

    MathSciNet  MATH  Google Scholar 

  25. Bourgain J (2000) On diffusion inhigh-dimensional Hamiltonian systems and PDE. J Anal Math 80:1–35

    MathSciNet  MATH  Google Scholar 

  26. Bourgain J (2005) Green's function estimates forlattice Schrödinger operators and applications. In: Annals of Mathematics Studies, vol 158. Princeton University Press,Princeton

    Google Scholar 

  27. Bourgain J (2005) On invariant tori of full dimension for 1D periodic NLS. J Funct Anal 229(1):62–94

    MathSciNet  MATH  Google Scholar 

  28. Bourgain J, Kaloshin V (2005) On diffusion in high-dimensionalHamiltonian systems. J Funct Anal 229(1):1–61

    MathSciNet  MATH  Google Scholar 

  29. Chernoff PR, Marsden JE (1974) Properties of infinite dimensional Hamiltoniansystems In: Lecture Notes in Mathematics, vol 425. Springer, Berlin

    MATH  Google Scholar 

  30. Cohen D, Hairer E, Lubich C (2008) Long-time analysis of nonlinearly perturbed wave equations via modulated Fourier expansions. Arch Ration Mech Anal 187(2)341–368

    MathSciNet  MATH  Google Scholar 

  31. Craig W (1996) Birkhoff normal forms for water waves In: Mathematical problemsin the theory of water waves (Luminy, 1995), Contemp Math, vol 200. Amer Math Soc, Providence, RI, pp 57–74

    Google Scholar 

  32. Craig W (2006) Surface water waves and tsunamis. J Dyn Differ Equ 18(3):525–549

    MathSciNet  MATH  Google Scholar 

  33. Craig W, Guyenne P, Kalisch H (2005) Hamiltonian long-wave expansions for freesurfaces and interfaces. Comm Pure Appl Math 58(12):1587–1641

    MathSciNet  MATH  Google Scholar 

  34. Craig W, Wayne CE (1993) Newton's method and periodic solutions of nonlinearwave equations. Comm Pure Appl Math 46:1409–1498

    MathSciNet  MATH  Google Scholar 

  35. Dell'Antonio GF (1989) Fine tuning of resonances and periodic solutions ofHamiltonian systems near equilibrium. Comm Math Phys 120(4):529–546

    MathSciNet  ADS  Google Scholar 

  36. Delort JM, Szeftel J (2004) Long-time existence for small data nonlinearKlein–Gordon equations on tori and spheres. Int Math Res Not 37:1897–1966

    MathSciNet  Google Scholar 

  37. Delort J-M, Szeftel J (2006) Long-time existence for semi-linearKlein–Gordon equations with small Cauchy data on Zoll manifolds. Amer J Math 128(5):1187–1218

    MathSciNet  MATH  Google Scholar 

  38. Dyachenko AI, Zakharov VE (1994) Is free-surface hydrodynamics anintegrable system? Phys Lett A 190:144–148

    MathSciNet  ADS  Google Scholar 

  39. Eliasson HL, Kuksin SB (2006) KAM for non-linear Schroedingerequation. Ann of Math. Preprint (to appear)

    Google Scholar 

  40. Fassò F (1990) Lie series method for vector fields and Hamiltonianperturbation theory. Z Angew Math Phys 41(6):843–864

    Google Scholar 

  41. Foias C, Saut JC (1987) Linearization and normal form of theNavier–Stokes equations with potential forces. Ann Inst H Poincaré Anal Non Linéaire 4:1–47

    Google Scholar 

  42. Gentile G, Mastropietro V, Procesi M (2005) Periodic solutions for completelyresonant nonlinear wave equations with Dirichlet boundary conditions. Comm Math Phys 256(2):437–490

    MathSciNet  ADS  MATH  Google Scholar 

  43. Grébert B (2007) Birkhoff normal form and Hamiltonian PDES. Partial differential equations and applications, 1–46 Sémin Congr, 15 Soc Math France, Paris

    Google Scholar 

  44. Hairer E, Lubich C (2006) Conservation of energy, momentum and actions innumerical discretizations of nonlinear wave equations

    Google Scholar 

  45. Kappeler T, Pöschel J (2003) KdV & KAM. Springer,Berlin

    Google Scholar 

  46. Klainerman S (1983) On almost global solutions to quasilinear wave equationsin three space dimensions. Comm Pure Appl Math 36:325–344

    MathSciNet  MATH  Google Scholar 

  47. Krol MS (1989) On Galerkin–averaging method for weakly nonlinear waveequations. Math Meth Appl Sci 11:649–664

    MathSciNet  MATH  Google Scholar 

  48. Kuksin SB (1987) Hamiltonian perturbations of infinite-dimensionallinear systems with an imaginary spectrum. Funct Anal Appl 21:192–205

    MathSciNet  MATH  Google Scholar 

  49. Kuksin SB (1993) Nearly integrableinfinite-dimensional Hamiltonian systems. Springer, Berlin

    MATH  Google Scholar 

  50. Kuksin SB, Pöschel J (1996) Invariant Cantor manifolds of quasi-periodicoscillations for a nonlinear Schrödinger equation. Ann Math 143:149–179

    Google Scholar 

  51. Lidskij BV, Shulman EI (1988) Periodic solutions of the equation\( { u_{tt}-u_{xx}+u^3=0 } \). Funct Anal Appl22:332–333

    MathSciNet  MATH  Google Scholar 

  52. Marsden J (1972) Darboux's theorem fails for weak symplectic forms. Proc AmerMath Soc 32:590–592

    MathSciNet  MATH  Google Scholar 

  53. Nekhoroshev NN (1977) Exponential estimate of the stability of near integrableHamiltonian systems. Russ Math Surv 32(6):1–65

    MATH  Google Scholar 

  54. Nikolenko NV (1986) The method of Poincaré normal form in problems ofintegrability of equations of evolution type. Russ Math Surv 41:63–114

    MathSciNet  MATH  Google Scholar 

  55. Paleari S, Bambusi D, Cacciatori S (2001) Normal form and exponentialstability for some nonlinear string equations. ZAMP 52:1033–1052

    MathSciNet  ADS  MATH  Google Scholar 

  56. Pals H (1996) The Galerkin–averaging method for the Klein–Gordonequation in two space dimensions. Nonlinear Anal TMA 27:841–856

    MathSciNet  MATH  Google Scholar 

  57. Pöschel J (2002) On the construction of almost-periodic solutions fora nonlinear Schrödinger equation. Ergod Th Dyn Syst 22:1–22

    Google Scholar 

  58. Soffer A, Weinstein MI (1999) Resonances, radiation damping and instability inHamiltonian nonlinear wave equations. Invent Math 136(1):9–74

    MathSciNet  ADS  Google Scholar 

  59. Stroucken ACJ, Verhulst F (1987) The Galerkin–averaging method fornonlinear, undamped continuous systems. Math Meth Appl Sci 335:520–549

    MathSciNet  Google Scholar 

  60. Wayne CE (1990) Periodic and quasi-periodic solutions of nonlinear waveequations via KAM theory. Comm Math Phys 127:479–528

    MathSciNet  ADS  MATH  Google Scholar 

  61. Weinstein A (1969) Symplectic structures on Banach manifolds. Bull Amer MathSoc 75:1040–1041

    MathSciNet  MATH  Google Scholar 

  62. Zakharov VE (1968) Stability of periodic waves of finite amplitude on thesurface of a deep fluid. Appl Mech Tech Phys 2:190–194

    ADS  Google Scholar 

  63. Zehnder E (1978) C L Siegel's linearization theorem in infinitedimensions. Manuscripta Math 23:363–371

    MathSciNet  MATH  Google Scholar 

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Bambusi, D. (2009). Perturbation Theory for PDEs. In: Meyers, R. (eds) Encyclopedia of Complexity and Systems Science. Springer, New York, NY. https://doi.org/10.1007/978-0-387-30440-3_401

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