Abstract
A moment map\(\tilde J_r :M_A \to (\widetilde{gl(r)}^ + )^*\) is constructed from the Poisson manifold ℳA of rank-r perturbations of a fixedN×N matrixA to the dual\((\widetilde{gl(r)}^ + )^*\) of the positive part of the formal loop algebra\(\widetilde{gl(r)}\)=gl(r)⊗ℂ[[λ, λ−1]]. The Adler-Kostant-Symes theorem is used to give hamiltonians which generate commutative isospectral flows on\((\widetilde{gl(r)}^ + )^*\). The pull-back of these hamiltonians by the moment map gives rise to commutative isospectral hamiltonian flows in ℳA. The latter may be identified with flows on finite dimensional coadjoint orbits in\((\widetilde{gl(r)}^ + )^*\) and linearized on the Jacobi variety of an invariant spectral curveX r which, generically, is anr-sheeted Riemann surface. Reductions of ℳA are derived, corresponding to subalgebras ofgl(r, ℂ) andsl(r, ℂ), determined as the fixed point set of automorphism groupes generated by involutions (i.e., all the classical algebras), as well as reductions to twisted subalgebras of\(\widetilde{sl(r,\mathbb{C}})\). The theory is illustrated by a number of examples of finite dimensional isospectral flows defining integrable hamiltonian systems and their embeddings as finite gap solutions to integrable systems of PDE's.
Similar content being viewed by others
References
Ablowitz, M.J., Kaup, D.J., Newell, A.C., Segur, H.: The inverse scattering transform-Fourier analysis for nonlinear problems. Stud. Appl. Math.53, 249–315 (1973)
Ablowitz, M.J., Segur, H.: Solitons and the inverse scattering transform. SIAM Studies in Applied mathematics,4, society for industrial and applied mathematics. Philadelphis 1981
Abraham, R., Marsden, J.E.: Foundations of mechanics, 2nd ed. Reading, MA: Benjamin/Cummings 1978, Chap. 4
Adams, M.R., Harnad, J., Hurtubise, J.: Isospectral hamiltonian flows in finite and infinite dimensions. II. Integration of flows (preprint) (1988)
Adler, M.: On a trace functional for formal pseudo-differential operators and the symplectic structure of the Korteweg-de Vries type equations. Invent. Math.50, 219–248 (1979)
Adler, M., van Moerbeke, P.: Completely integrable systems, euclidean Lie algebras, and curves. Adv. Math.38, 267–317 (1980)
Adler, M., van Moerbeke, P.: Linearization of Hamiltonian systems, Jacobi varieties, and representation theory. Adv. Math.38, 318–379 (1980)
Date, E., Tanaka, S.: Periodic multi-soliton solutions of the Korteweg-de Vries equation and Toda lattice. Prog. Theor. Phys. [Suppl.]59, 107 (1976)
Date, E., Jimbo, M., Kashiwara, M., Miwa, T.: Proc. Jpn. Acad.57A, 342 and 387 (1981); Physica4D, 343 (1982); J. Phys. Soc. Jpn.50, 3806 and 3813 (1981); Publ. RIMS Kyoto Univ.18, 1077 (1982)
Deift, P., Lund, F., Trubowitz, E.: Nonlinear wave equations and constrained harmonic motion. Commun. Math. Phys.74, 141–188 (1980)
Dhooge, P.: Bäcklund transformations on Kac-Moody Lie algebras and integrable systems. J. Geom. Phys.1, 9–38 (1984)
Dubrovin, B.A.: Theta functions and non-linear equations. Russ. Math. Surv.36, 11–92 (1981)
Flaschka, H.: Towards an algebro-geometric interpretation of the Neumann system. Tohoku Math. J.36, 407–426 (1984)
Flaschka, H., Newell, A.C., Ratiu, T.: Kac-Moody Lie algebras and soliton equations. II. Lax equations associated withA (1)1 . Physica9D, 300 (1983)
Kac-Moody Lie algebras and soliton equations. III. Stationary equations associated withA (1)1 . Physica9D, 324–332 (1983)
Forest, M.G., McLaughlin, D.W.: Spectral theory for the periodic sine-Gordon equation: a concrete viewpoint. J. Math. Phys.23, 1248–1277 (1982)
Gagnon, L., Harnad, J., Hurtubise, J., Winternitz, P.: Abelian integrals and the reduction method for an integrable Hamiltonian system. J. Math. Phys.26, 1605–1612 (1985)
Guillemin, V., Sternberg, S.: Symplectic techniques in physics. Cambridge: Cambridge University Press 1984
Guillemin, V., Sternberg, S.: The moment map and collective motion. Ann. Phys.127, 220–253 (1980)
Guillemin, V., Sternberg, S.: On collective complete integrability according to the method of Thimm. Ergodic Dyn. Sys.3, 219–230 (1983)
Guillemin, V., Sternberg, S.: On the method of Symes for integrating systems of the Toda type. Lett. Math. Phys.7, 113–115 (1983)
Harnad, J., Saint-Aubin, Y., Shnider, S.: Bäcklund transformations for nonlinear sigma models with values. In: Riemannian symmetric spaces. Commun. Math. Phys.93, 33–56 (1984)
The soliton correlation matrix and the reduction problem for integrable systems. Commun. Math. Phys.92, 329–367 (1984)
Helgason, S.: Differential geometry and symmetric spaces. New York: Academic Press 1962, Chap. IX
Hurtubise, J.: Rankr perturbations, algebraic curves, and ruled surfaces, preprint U.Q.A.M. (1986)
Kostant, B.: The solution to a generalized Toda lattice and representation theory. Adv. Math.34, 195–338 (1979)
Krichever, I.M.: Algebraic curves and commuting matrix differential operators. Funct. Anal. Appl.10, 144–146 (1976)
Krichever, I.M.: Methods of algebraic geometry in the theory of non-linear equations. Russ. Math. Surv.32, 6, 185–213 (1977)
Krichever, I.M., Novikov, S.P.: Holomorphic bundles over algebraic curves and non-linear equations. Russ. Math. Surv.35, 6, 53 (1980)
McKean, H.P., Trubowitz, E.: Hill's operator and hyperelliptic function theory in the presence of infinitely many branched points. CPAM29, 143–226 (1976); Hill's surfaces and their theta functions, Bull. AMS84, 1042–1085 (1979)
Mischenko, A.S., Fomenko, A.T.: Generalized Liouville method of integration of Hamiltonian systems. Funct. Anal. Appl.12, 113–121 (1978)
Mischenko, A.S., Fomenko, A.T.: Integrability of Euler equations on semisimple Lie algebras. Sel. Math. Sov.2, 207–291 (1982)
van Moerbeke, P., Mumford, D.: The spectrum of difference operators and algebraic curves. Acta Math.143, 93–154 (1979)
Moser, J.: Geometry of quadrics and spectral theory. The chern symposium, Berkeley, June 1979; p. 147–188. Berlin, Heidelberg, New York: Springer 1980
Moser, J.: Various aspects of integrable Hamiltonian systems, Proc. CIME Conference, Bressanone, Italy, June 1978; Prog. Math.8. Boston: Birkhäuser 1980
Mumford, D.: Tata lectures of theta. II. Prog. Math.43. Boston: Birkhäuser 1983
Pressley, A., Segal, G.: Loop groups. Oxford: Oxford University Press 1986
Previato, E.: Hyperelliptic quasi-periodic and soliton solutions of the nonlinear Schrödinger equation. Duke Math. J.52 (1985)
Ratiu, T.: The C. Neumann problem as a completely integrable system on an adjoint orbit. Trans. AMS264, 321–329 (1981);
The Lie algebraic interpretation of the complete integrability of the Rosochatius system. In: Mathematical methods in hydrodynamics and integrability in dynamical systems. AIP Conf. Proc.88, La Jolla, 1981
Reyman, A.G., Semenov-Tian-Shansky, M.A.: Reduction of Hamiltonian systems, affine Lie algebras and Lax equations. Invent. Math.54, 81–100 (1979)
Reyman, A.G., Semenov-Tian-Shansky, M.A.: Reduction of Hamiltonian systems, affine Lie algebras and Lax equations II. Invent. Math.63, 423–432 (1981)
Reyman, A.G., Semenov-Tian-Shansky, M.A., Frenkel, I.B.: Graded Lie algebras and completely integrable dynamical systems. Sov. Math. Doklady20, 811–814 (1979)
Sato, M.: Soliton equations as dynamical systems on infinite dimensional Grassmann manifolds RIMS Kokyuroku439, 30–46 (1981);
with Sato, Y.: Soliton equations as dynamical systems on infinite dimensional Grassmann manifolds. In: Nonlinear PDE's in applied science U.S.-Japan Seminar, Tokyo 1982, Lax, P., Fujita, H. (eds.). Amsterdam: North-Holland 1982
Segal, G., Wilson, G.: Loop groups and equations of KdV type. Publ. Math. IHES61, 6–65 (1985)
Schilling, R.: Trigonal curves and operator deformation theory (preprint)
Symes, W.W.: Systems of Toda type, inverse spectral problems, and representation theory. Invent. Math.59, 13–59 (1980)
Ting, A.C., Tracy, E.R., Chen, H.H., Lee, Y.C.: Reality constraints for the periodic sine-Gordon equation, Phys. Rev. A30, 3355–3358 (1984)
Tracy, E.R., Chen, H.H., Lee, Y.C.: Study of quasi-periodic solutions of the nonlinear Schrödinger equation and the nonlinear modulational instability. Phys. Rev. Lett.53, 218–221 (1984)
Weinstein, A.: Lectures on symplectic manifolds. CBMS Conference Series, Vol. 29. Providence, RI: Am. Math. Soc. 1977
Weinstein, A.: The local structure of Poisson manifolds. J. Differ. Geom.18, 523–557 (1983)
Wilson, G.: Habillage et fonctions τ. C.R. Acad. Soc.299, 587–590 (1984)
Zakharov, V.E., Shabat, A.B.: A scheme for integrating the nonlinear equations of mathematical physics by the method of the inverse scattering problem. I. Funct. Anal. Appl.8, 226–235 (1974)
Zakharov, V.E., Shabat, A.B.: Integration of nonlinear equations of mathematical physics by the method of inverse scattering. II. Funct. Anal. Appl.18, 166–174 (1979)
Author information
Authors and Affiliations
Additional information
Communicated by A. Jaffe
This research was partially supported by NSF grants MCS-8108814 (A03), DMS-8604189, and DMS-8601995
Rights and permissions
About this article
Cite this article
Adams, M.R., Harnad, J. & Previato, E. Isospectral hamiltonian flows in finite and infinite dimensions. Commun.Math. Phys. 117, 451–500 (1988). https://doi.org/10.1007/BF01223376
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF01223376