×

On Darboux-Treibich-Verdier potentials. (English) Zbl 1242.34152

In the article, certain spaces of potentials of the Schrödinger operator \(-{d^2\over dz^2}+ u(z)\) are studied. The potential \(u(z)\) is called finite-gap if the operator has a finite number of gaps in its spectrum. A linear subspace \(V\) spanned by \(n\) meromorphic functions is called finite-gap if it contains an infinite subset \(K\subset V\) consisting of finite-gap potentials, such that \(K\) is dense in \(V\) in the Zariski topology. The subspace \(V\) is maximal if it is not contained in a larger finite-gap space.
The main result of the article claims that there are only three maximal finite-gap subspaces, of dimensions \(n= 5\), \(3\) and \(2\). The most general five-dimensional subspace is spanned by \(1\), the classical Weierstrass elliptic function and its shifts by three half-periods. It contains an infinite number of finite-gap Darboux-Treibich-Verdier potentials.
The crucial property of the finite-gap operators under consideration is the Painlevé-Kowalevskaya property: all solutions of the corresponding Schrödinger equation \[ -\psi''+ u(z)\psi= \lambda\psi \] are meromorphic in the whole complex plane for all \(\lambda\). The finite-gap potentials are also known to have only second-order poles with zero residues.
The author also notes that the set of all elliptic finite-gap potentials is much bigger than the Darboux-Treibich-Verdier family and its effective description is still to be done.

MSC:

34M05 Entire and meromorphic solutions to ordinary differential equations in the complex domain
81R12 Groups and algebras in quantum theory and relations with integrable systems
34M35 Singularities, monodromy and local behavior of solutions to ordinary differential equations in the complex domain, normal forms

References:

[1] Airault H., McKean H.P., Moser J.: Rational and elliptic solutions of the Korteweg–de Vries equation and a related many-body problem. Commun. Pure Appl. Math. 30, 95–148 (1977) · Zbl 0338.35024 · doi:10.1002/cpa.3160300106
[2] Burchnall J.-L., Chaundy T.W.: Commutative ordinary differential operators. Proc. Lond. Math. Soc. 21, 420–440 (1923) · JFM 49.0311.03 · doi:10.1112/plms/s2-21.1.420
[3] Burchnall J.-L., Chaundy T.W.: Commutative ordinary differential operators. Proc. R. Soc. Lond. (A) 118, 557–583 (1928) · JFM 54.0439.01 · doi:10.1098/rspa.1928.0069
[4] Chalykh O., Etingof P., Oblomkov A.: Generalized Lamé operators. Commun. Math. Physics. 239(1–2), 115–153 (2003) · Zbl 1119.34066 · doi:10.1007/s00220-003-0869-6
[5] Chalykh O.A., Feigin M.V., Veselov A.P.: Multidimensional Baker–Akhiezer functions and Huygens’ principle. Commun. Math. Phys. 206, 533–566 (1999) · Zbl 0972.35110 · doi:10.1007/PL00005521
[6] Darboux G.: Sur une équation linéare. C. R. Acad. Sci. Paris, t. XCIV(25), 1645–1648 (1882) · JFM 14.0278.01
[7] Darboux, G.: Lecons sur la théorie des surfaces, vol. 2, pp. 210–215. Gauthier-Villars, Paris (1915)
[8] Dubrovin B.A., Novikov S.P.: Periodic and conditionally periodic analogs of the many-soliton solutions of the Korteweg–de Vries equation. Sov. Phys. JETP 40(6), 1058–1063 (1974)
[9] Dubrovin B.A., Matveev V.B., Novikov S.P.: Non-linear equations of the KdV type, finite-gap linear operators and abelian varieties. Russ. Math. Surv. 31, 55–136 (1976) · Zbl 0346.35025 · doi:10.1070/RM1976v031n01ABEH001446
[10] Dubrovin B.A.: Periodic problems for the Korteweg–de Vries equation in the class of finite-gap potentials. Funct. Anal. Appl. 9, 215–223 (1975) · Zbl 0358.35022 · doi:10.1007/BF01075598
[11] Duistermaat J.J., Grünbaum F.A.: Differential equations in the spectral parameter. Commun. Math. Phys. 103, 177–240 (1986) · Zbl 0625.34007 · doi:10.1007/BF01206937
[12] Gaillard P., Matveev V.B.: Wronskian and Casorati determinant representations for Darboux–Pöschl–Teller potentials and their difference analogue. J. Phys. A Math. Theor. 42, 404009 (2009) · Zbl 1192.65094 · doi:10.1088/1751-8113/42/40/404009
[13] Gesztesy F., Weikard R.: Picard potentials and Hill’s equation on a torus. Acta Math. 176, 73–107 (1996) · Zbl 0927.37040 · doi:10.1007/BF02547336
[14] Gibbons J., Veselov A.P.: On the rational monodromy-free potentials with sextic growth. J. Math. Phys. 50(1), 013–513 (2009) · Zbl 1200.34108 · doi:10.1063/1.3001604
[15] Hemery A.D., Veselov A.P.: Whittaker–Hill equation and semifinite-gap Schrödinger operators. J. Math. Phys. 51, 072–108 (2010) · Zbl 1311.34171 · doi:10.1063/1.3455367
[16] Inozemtsev V.I.: Lax representation with spectral parameter on torus for integrable particle systems. Lett. Math. Phys. 17, 11–17 (1989) · Zbl 0679.70005 · doi:10.1007/BF00420008
[17] Its A.R., Matveev V.B.: Schrödinger operators with finite-gap spectrum and N-soliton solutions of the Korteweg–de Vries equation. Theor. Math. Phys. 23, 343–355 (1975) · doi:10.1007/BF01038218
[18] Krichever I.M.: Methods of algebraic geometry in the theory of non-linear equations. Russ. Math. Surv. 82(6), 185–213 (1977) · Zbl 0386.35002 · doi:10.1070/RM1977v032n06ABEH003862
[19] Lax P.D.: Periodic solutions of the KdV equation. Commun. Pure Appl. Math. 28(2), 141–188 (1975) · doi:10.1002/cpa.3160280105
[20] Matveev V.B., Smirnov A.: On the link between the Sparre equation and Darboux–Treibich–Verdier equation. Lett. Math. Phys. 76, 283–295 (2006) · Zbl 1133.34002 · doi:10.1007/s11005-006-0074-6
[21] Novikov S.P.: The periodic problem for the Korteweg–de Vries equation. Funct. Anal. Appl. 8, 236–246 (1974) · Zbl 0299.35017 · doi:10.1007/BF01075697
[22] Segal G., Wilson G.: Loop groups and equations of KdV type. Publ. Inst. Hautes Etudes Sci. Publ. Math. 61, 5–65 (1985) · Zbl 0592.35112 · doi:10.1007/BF02698802
[23] Smirnov A.O.: Finite-gap solutions of the Fuchsian equation. Lett. Math. Phys. 76, 297–316 (2006) · Zbl 1136.34065 · doi:10.1007/s11005-006-0070-x
[24] Taimanov I.A.: On two-gap elliptic potentials. Acta Appl. Math. 36, 119–124 (1994) · Zbl 0843.33011 · doi:10.1007/BF01001545
[25] Treibich, A., Verdier, J.-L.: Solitons elliptiques. Progr. Math. (The Grothendieck Festschrift, vol. 3). v.88, pp. 437–480. Birkhäuser, Boston (1990) · Zbl 0726.14024
[26] Verdier J.-L.: New elliptic solitons. In: Kashiwara, M., Kawai, T. (eds) Algebraic Analysis, pp. 901–910. Academic Press, Boston (1988)
[27] Veselov A.P.: On Stieltjes relations, Painlevé-IV hierarchy and complex monodromy. J. Phys A. Math. Gen. 34, 3511–3519 (2001) · Zbl 1045.34060 · doi:10.1088/0305-4470/34/16/318
[28] Whittaker E.T., Watson G.N.: A Course of Modern Analysis. Cambridge University Press, Cambridge (1963) · Zbl 0108.26903
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.