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Submitter: None Authors: Jongbae Kim (ETRI), Q-Han Park and H.J. Shin (Kyunghee U.) Title: Conservation Laws in Higher-Order Nonlinear Optical Effects Abstract: Conservation laws of the nonlinear Schr\"{o}dinger equation are studied in the presence of higher-order nonlinear optical effects including the third-order dispersion and the self-steepening. In a context of group theory, we derive a general expression for infinitely many conserved currents and charges of the coupled higher-order nonlinear Schr\"{o}dinger equation. The first few currents and charges are also presented explicitly. Due to the higher-order effects, conservation laws of the nonlinear Schr\"{o}dinger equation are violated in general. The differences between the types of the conserved currents for the Hirota and the Sasa-Satsuma equations imply that the higher-order terms determine the inherent types of conserved quantities for each integrable cases of the higher-order nonlinear Schr\"{o}dinger equation. Journal: Phys. Rev. E {\bf 58} 6746, 1998
Submitter: None Authors: Q-Han Park and H.J. Shin (Kyunghee U.) Title: Painlev\'{e} analysis of the coupled nonlinear Schr\"{o}dinger equation for polarized optical waves in an isotropic medium Abstract: Using the Painlev\'{e} analysis, we investigate the integrability properties of a system of two coupled nonlinear Schr\"{o}dinger equations that describe the propagation of orthogonally polarized optical waves in an isotropic medium. Besides the well-known integrable vector nonlinear Schr\"{o}dinger equation, we show that there exist a new set of equations passing the Painlev\'{e} test where the self and cross phase modulational terms are of different magnitude. We introduce the Hirota bilinearization and the B\"{a}cklund transformation to obtain soliton solutions and prove integrability by making a change of variables. The conditions on the third-order susceptibility tensor $\chi^{(3)} $ imposed by these new integrable equations are explained. Journal: Phys. Rev. E {\bf 59} 2373, 1999
Submitter: Baryakhtar Authors: I.V.Baryakhtar, V.G.Baryakhtar, E.N.Economou Title: Kinetic and Transport Equations for Localized Excitations in Sine-Gordon Model Abstract: We analyze the kinetic behavior of localized excitations - solitons, breathers and phonons - in Sine-Gordon model. Collision integrals for all type of localized excitation collision processes are constructed, and the kinetic equations are derived. We analyze the kinetic behavior of localized excitations - solitons, breathers and phonons - in Sine-Gordon model. Collision integrals for all type of localized excitation collision processes are constructed, and the kinetic equations are derived. We prove that the entropy production in the system of localized excitations takes place only in the case of inhomogeneous distribution of these excitations in real and phase spaces. We derive transport equations for soliton and breather densities, temperatures and mean velocities i.e. show that collisions of localized excitations lead to creation of diffusion, thermoconductivity and intrinsic friction processes. The diffusion coefficients for solitons and breathers, describing the diffusion processes in real and phase spaces, are calculated. It is shown that diffusion processes in real space are much faster than the diffusion processes in phase space. Journal: None
Submitter: Nugmanova G. N. Authors: R. Myrzakulov Title: On the M-XX equation Abstract: The (2+1)-dimensional integrable M-XX equation is considered. Journal: None
Submitter: Paul Fendley Authors: P. Fendley and H. Saleur Title: Differential equations and duality in massless integrable field theories at zero temperature Abstract: Functional relations play a key role in the study of integrable models. We argue in this paper that for massless field theories at zero temperature, these relations can in fact be interpreted as monodromy relations. Combined with a recently discovered duality, this gives a way to bypass the Bethe ansatz, and compute directly physical quantities as solutions of a linear differential equation, or as integrals over a hyperelliptic curve. We illustrate these ideas in details in the case of the $c=1$ theory, and the associated boundary sine-Gordon model. Journal: Nucl.Phys.B574:571-586,2000
Submitter: Sergei M. Sergeev Authors: S. Sergeev Title: Solitons in a 3d integrable model Abstract: Equations of motion for a classical 3d discrete model, whose auxialiary system is a linear system, are investigated. The Lagrangian form of the equations of motion is derived. The Lagrangian variables are a triplet of "tau functions". The equations of motion for the Triplet of Tau functions are Three Trilinear equations. Simple solitons for the trilinear equations are given. Both the dispersion relation and the phase shift reflect the triplet structure of equations. Journal: None
Submitter: Robert Milson Authors: Niky Kamran, Robert Milson, Peter Olver Title: Invariant Modules and the Reduction of Nonlinear Partial Differential Equations to Dynamical Systems Abstract: We completely characterize all nonlinear partial differential equations leaving a given finite-dimensional vector space of analytic functions invariant. Existence of an invariant subspace leads to a re duction of the associated dynamical partial differential equations to a system of ordinary differential equations, and provide a nonlinear counterpart to quasi-exactly solvable quantum Hamiltonians. These results rely on a useful extension of the classical Wronskian determinant condition for linear independence of functions. In addition, new approaches to the characterization o f the annihilating differential operators for spaces of analytic functions are presented. Journal: None
Submitter: Nikolay Asenov Kostov Authors: N.A.Kostov, Z.T. Kostova Title: Nonlinear waves, differential resultant, computer algebra and completely integrable dynamical systems Abstract: The hierarchy of integrable equations are considered. The dynamical approach to the theory of nonlinear waves is proposed. The special solutions(nonlinear waves) of considered equations are derived. We use powerful methods of computer algebra such differential resultant and others. Journal: None
Submitter: Nikolay Asenov Kostov Authors: N.A. Kostov Title: Korteweg-de Vries hierarchy and related completely integrable systems: I. Algebro-geometrical approach Abstract: We consider complementary dynamical systems related to stationary Korteweg-de Vries hierarchy of equations. A general approach for finding elliptic solutions is given. The solutions are expressed in terms of Novikov polynomials in general quais-periodic case. For periodic case these polynomials coincide with Hermite and Lam\'e polynomials. As byproduct we derive $2\times 2$ matrix Lax representation for Rosochatius-Wojciechiwski, Rosochatius, second flow of stationary nonlinear vectro Schr\"{o}dinger equations and complex Neumann system. Journal: None
Submitter: Nikolay Asenov Kostov Authors: P.L. Christiansen, J.C. Eilbeck, V.Z. Enolskii, and N.A. Kostov Title: Quasi-Periodic and Periodic Solutions for Systems of Coupled Nonlinear SCHR\"Odinger Equations Abstract: We consider travelling periodic and quasiperiodic wave solutions of a set of coupled nonlinear Schr\"odimger equations. In fibre optics these equations can be used to model single mode fibers with strong birefringence and two-mode optical fibres. Recently these equations appear as modes, which describe pulse-pulse interaction in wavelength-division-multiplexed channels of optical fiber transmission systems. Two phase quasi-periodic solutions for integrable Manakov system are given in tems of two-dimensional Kleinian functions. The reduction of quasi-periodic solutions to elliptic functions is dicussed. New solutions in terms of generalized Hermite polynomilas, which are associated with two-gap Treibich-Verdier potentials are found. Journal: None
Submitter: Sudipta Nandy Authors: Sasanka Ghosh, Anjan Kundu, Sudipta Nandy Title: Soliton solutions, Liouville integrability and gauge equivalence of Sasa Satsuma equation Abstract: Exact integrability of the Sasa Satsuma eqation (SSE) in the Liouville sense is established by showing the existence of an infinite set of conservation laws. The explicit form of the conserved quantities in term of the fields are obtained by solving the Riccati equation for the associated 3x3 Lax operator. The soliton solutions in particular, one and two soliton solutions, are constructed by the Hirota's bilinear method. The one soliton solutions is also compared with that found through the inverse scattering method. The gauge equivalence of the SSE with a generalized Landau Lifshitz equation is established with the explicit construction o Journal: None
Submitter: Sudipta Nandy Authors: Sasanka Ghosh, Sudipta Nandy Title: Optical solitons in higher order nonlinear Schrodinger equation Abstract: We show the complete integrability and the existence of optical solitons of higher order nonlinear Schrodinger equation by inverse scattering method for a wide range of values of coefficients. This is achieved first by invoking a novel connection between the integrability of a nonlinear evolution equation and the dimensions of a family of matrix Lax pairs. It is shown that Lax pairs of different dimensions lead to the same evolution equation only with the coefficients of the terms in different integer ratios. Optical solitons, thus obtained by inverse scattering method, have been found by solving an n dimensional eigenvalue problem. Journal: None
Submitter: Dr P. K. Panigrahi Authors: C. Nagaraja Kumar and Prasanta K. Panigrahi (School of Physics, University of Hyderabad, Hyderabad, India) Title: Compacton-like Solutions for Modified KdV and other Nonlinear Equations Abstract: We present compacton-like solution of the modified KdV equation and compare its properties with those of the compactons and solitons. We further show that, the nonlinear Schr{\"o}dinger equation with a source term and other higher order KdV-like equations also possess compact solutions of the similar form. Journal: None
Submitter: Sudipta Nandy Authors: Sasanka Ghosh and Sudipta Nandy Title: Inverse scattering method and vector higher order nonlinear Schrodinger equation Abstract: A generalised inverse scattering method has been developed for arbitrary n dimensional Lax equations. Subsequently, the method has been used to obtain N soliton solutions of a vector higher order nonlinear Schrodinger equation, proposed by us. It has been shown that under suitable reduction, vector higher order nonlinear Schrodinger equation reduces to higher order nonlinear Schrodinger equation. The infinite number of conserved quantities have been obtained by solving a set of coupled Riccati equation. A gauge equivalence is shown between the vector higher order nonlinear Schrodinger equation and the generalized Landau Lifshitz equation and the Lax pair for the latter equation has also been constructed in terms of the spin field, establishing direct integrability of the spin system. Journal: None
Submitter: Unal Goktas Authors: Willy Hereman (Colorado School of Mines), Unal Goktas (Wolfram Research, Inc.) Title: Integrability Tests for Nonlinear Evolution Equations Abstract: Discusses several integrability tests for nonlinear evolution equations. Journal: None
Submitter: Andrew Pickering Authors: Pilar R. Gordoa, Nalini Joshi and Andrew Pickering Title: Mappings preserving locations of movable poles: a new extension of the truncation method to ordinary differential equations Abstract: The truncation method is a collective name for techniques that arise from truncating a Laurent series expansion (with leading term) of generic solutions of nonlinear partial differential equations (PDEs). Despite its utility in finding Backlund transformations and other remarkable properties of integrable PDEs, it has not been generally extended to ordinary differential equations (ODEs). Here we give a new general method that provides such an extension and show how to apply it to the classical nonlinear ODEs called the Painleve equations. Our main new idea is to consider mappings that preserve the locations of a natural subset of the movable poles admitted by the equation. In this way we are able to recover all known fundamental Backlund transformations for the equations considered. We are also able to derive Backlund transformations onto other ODEs in the Painleve classification. Journal: None
Submitter: Svetlana Pacheva-Nissimov Authors: Henrik Aratyn, Emil Nissimov and Svetlana Pacheva Title: Multi-Component Matrix KP Hierarchies as Symmetry-Enhanced Scalar KP Hierarchies and Their Darboux-B"acklund Solutions Abstract: We show that any multi-component matrix KP hierarchy is equivalent to the standard one-component (scalar) KP hierarchy endowed with a special infinite set of abelian additional symmetries, generated by squared eigenfunction potentials. This allows to employ a special version of the familiar Darboux-B"acklund transformation techniques within the ordinary scalar KP hierarchy in the Sato formulation for a systematic derivation of explicit multiple-Wronskian tau-function solutions of all multi-component matrix KP hierarchies. Journal: None
Submitter: Polterovich Iosif Authors: Iosif Polterovich Title: From Agmon-Kannai expansion to Korteweg-de Vries hierarchy Abstract: We present a new method for computation of the Korteweg-de Vries hierarchy via heat invariants of the 1-dimensional Schrodinger operator. As a result new explicit formulas for the KdV hierarchy are obtained. Our method is based on an asymptotic expansion of resolvent kernels of elliptic operators due to S.Agmon and Y.Kannai. Journal: None
Submitter: Katrina Elfrieda Hibberd Authors: Katrina Hibberd, Itzhak Roditi, Jon Links and Angela Foerster Title: Bethe ansatz solution of the closed anisotropic supersymmetric U model with quantum supersymmetry Abstract: The nested algebraic Bethe ansatz is presented for the anisotropic supersymmetric $U$ model maintaining quantum supersymmetry. The Bethe ansatz equations of the model are obtained on a one-dimensional closed lattice and an expression for the energy is given. Journal: None
Submitter: Alexander Turbiner Authors: Alexander Turbiner, Pavel Winternitz Title: Solutions of Non-linear Differential and Difference Equations with Superposition Formulas Abstract: Matrix Riccati equations and other nonlinear ordinary differential equations with superposition formulas are, in the case of constant coefficients, shown to have the same exact solutions as their group theoretical discretizations. Explicit solutions of certain classes of scalar and matrix Riccati equations are presented as an illustration of the general results. Journal: None
Submitter: Takayuki Tsuchida Authors: T. Tsuchida, M. Wadati Title: New integrable systems of derivative nonlinear Schr\"{o}dinger equations with multiple components Abstract: The Lax pair for a derivative nonlinear Schr\"{o}dinger equation proposed by Chen-Lee-Liu is generalized into matrix form. This gives new types of integrable coupled derivative nonlinear Schr\"{o}dinger equations. By virtue of a gauge transformation, a new multi-component extension of a derivative nonlinear Schr\"{o}dinger equation proposed by Kaup-Newell is also obtained. Journal: Phys. Lett. A 257 (1999) 53-64
Submitter: Luis Martinez Alonso Authors: Boris Konopelchenko and Luis Martinez Alonso Title: The KP Hierarchy in Miwa Coordinates Abstract: A systematic reformulation of the KP hierarchy by using continuous Miwa variables is presented. Basic quantities and relations are defined and determinantal expressions for Fay's identities are obtained. It is shown that in terms of these variables the KP hierarchy gives rise to a Darboux system describing an infinite-dimensional conjugate net. Journal: None
Submitter: R. Radhakrishnan Authors: R. Radhakrishnan, A. Kundu and M. Lakshmanan Title: Coupled nonlinear Schrodinger equations with cubic-quintic nonlinearity: Integrability and soliton interaction in non-Kerr media Abstract: We propose an integrable system of coupled nonlinear Schrodinger equations with cubic-quintic terms describing the effects of quintic nonlinearity on the ultra-short optical soliton pulse propagation in non-Kerr media. Lax pair, conserved quantities and exact soliton solutions for the proposed integrable model are given. Explicit form of two-solitons are used to study soliton interaction showing many intriguing features including inelastic (shape changing) scattering. Another novel system of coupled equations with fifth-degree nonlinearity is derived, which represents vector generalization of the known chiral-soliton bearing system. Journal: None
Submitter: Hubert Saleur Authors: H. Saleur Title: The continuum limit of sl(N/K) integrable super spin chains Abstract: I discuss in this paper the continuum limit of integrable spin chains based on the superalgebras sl(N/K). The general conclusion is that, with the full ``supersymmetry'', none of these models is relativistic. When the supersymmetry is broken by the generator of the sub u(1), Gross Neveu models of various types are obtained. For instance, in the case of sl(N/K) with a typical fermionic representation on every site, the continuum limit is the GN model with N colors and K flavors. In the case of sl(N/1) and atypical representations of spin j, a close cousin of the GN model with N colors, j flavors and flavor anisotropy is obtained. The Dynkin parameter associated with the fermionic root, while providing solutions to the Yang Baxter equation with a continuous parameter, thus does not give rise to any new physics in the field theory limit. These features are generalized to the case where an impurity is embedded in the system. Journal: Nucl.Phys. B578 (2000) 552-576
Submitter: Ruslan Sharipov Authors: R. F. Bikbaev, R. A. Sharipov Title: Magnetization waves in Landau-Lifshitz Model Abstract: The solutions of the Landau-Lifshitz equation with finite-gap behavior at infinity are considered. By means of the inverse scattering method the large-time asymptotics is obtained. Journal: Phys. Lett. 134A (1988), no. 2, 105-107.
Submitter: Takeo Kojima Authors: H. Furutsu and T. Kojima (Nihon Univ.) Title: $U_q(\hat{sl}_n)$-analog of the XXZ chain with a boundary Abstract: We study $U_q(\hat{sl}_n)$ analog of the XXZ spin chain with a boundary magnetic field h. We construct explicit bosonic formulas of the vacuum vector and the dual vacuum vector with a boundary magnetic field. We derive integral formulas of the correlation functions. Journal: J.Math.Phys. 41 (2000) 4413-4436
Submitter: Nalini Joshi Authors: Nalini Joshi, Johannes A. Petersen, and Luke M. Schubert Title: Nonexistence results for the Korteweg-deVries and Kadomtsev-Petviashvili equations Abstract: We study characteristic Cauchy problems for the Korteweg-deVries (KdV) equation $u_t=uu_x+u_{xxx}$, and the Kadomtsev-Petviashvili (KP) equation $u_{yy}=\bigl(u_{xxx}+uu_x+u_t\bigr)_x$ with holomorphic initial data possessing nonnegative Taylor coefficients around the origin. For the KdV equation with initial value $u(0,x)=u_0(x)$, we show that there is no solution holomorphic in any neighbourhood of $(t,x)=(0,0)$ in ${\mathbb C}^2$ unless $u_0(x)=a_0+a_1x$. This also furnishes a nonexistence result for a class of $y$-independent solutions of the KP equation. We extend this to $y$-dependent cases by considering initial values given at $y=0$, $u(t,x,0)=u_0(x,t)$, $u_y(t,x,0)=u_1(x,t)$, where the Taylor coefficients of $u_0$ and $u_1$ around $t=0$, $x=0$ are assumed nonnegative. We prove that there is no holomorphic solution around the origin in ${\mathbb C}^3$ unless $u_0$ and $u_1$ are polynomials of degree 2 or lower. Journal: None
Submitter: Askold Perelomov Authors: L. Gavrilov (U. Paul Sabatier, Toulouse), A. Perelomov (MPIM Bonn) Title: On the explicit solutions of the elliptic Calogero system Abstract: Let $q_1,q_2,...,q_N$ be the coordinates of $N$ particles on the circle, interacting with the integrable potential $\sum_{j<k}^N\wp(q_j-q_k)$, where $\wp$ is the Weierstrass elliptic function. We show that every symmetric elliptic function in $q_1,q_2,...,q_N$ is a meromorphic function in time. We give explicit formulae for these functions in terms of genus $N-1$ theta functions. Journal: None
Submitter: Doc. Dr. Ayse Humeyra Bilge Authors: Ayse Humeyra Bilge Title: A System with a Recursion Operator but One Higher Local Symmetry of the Form $u_t=u_{xxx}+f(t,x,u,u_x,u_{xx})$ Abstract: We construct a recursion operator for the system $(u_t,v_t)=(u_4+v^2,1/5 v_4)$, for which only one local symmetry is known and we show that the action of the recursion operator on $(u_t,v_t)$ is a local function. Journal: Lie Groups and Their Applications, Vol.1, No 2, pp.132-139, (1994)
Submitter: H. J. S. Dorren Authors: H.J.S. Dorren and J.J.B. van den Heuvel Title: On pulse broadening for optical solitons Abstract: Pulse broadening for optical solitons due to birefringence is investigated. We present an analytical solution which describes the propagation of solitons in birefringent optical fibers. The special solutions consist of a combination of purely solitonic terms propagating along the principal birefringence axes and soliton-soliton interaction terms. The solitonic part of the solutions indicates that the decay of initially localized pulses could be due to different propagation velocities along the birefringence axes. We show that the disintegration of solitonic pulses in birefringent optical fibers can be caused by two effects. The first effect is similar as in linear birefringence and is related to the unequal propagation velocities of the modes along the birefringence axes. The second effect is related to the nonlinear soliton-soliton interaction between the modes, which makes the solitonic pulse-shape blurred. Journal: None
Submitter: David H. Sattinger Authors: Richard Beals, D.H. Sattinger, and J. Szmigielski Title: Multipeakons and the Classical Moment Problem Abstract: Classical results of Stieltjes are used to obtain explicit formulas for the peakon-antipeakon solutions of the Camassa-Holm equation. The closed form solution is expressed in terms of the orthogonal polynomials of the related classical moment problem. It is shown that collisions occur only in peakon-antipeakon pairs, and the details of the collisions are analyzed using results {}from the moment problem. A sharp result on the steepening of the slope at the time of collision is given. Asymptotic formulas are given, and the scattering shifts are calculated explicitly Journal: None
Submitter: David H. Sattinger Authors: Yi Li and D.H. Sattinger Title: Soliton Collisions in the Ion Acoustic Plasma Equations Abstract: Numerical experiments involving the interaction of two solitary waves of the ion acoustic plasma equations are described. An exact 2-soliton solution of the relevant KdV equation was fitted to the initial data, and good agreement was maintained throughout the entire interaction. The data demonstrates that the soliton interactions are virtually elastic Journal: Journal of Mathematical Fluid Mechanics, volume 1, (1999), pp. 117-130
Submitter: Antonio Lima Santos Authors: A. Lima-Santos Title: Reflection K-Matrices for 19-Vertex Models Abstract: We derive and classify all regular solutions of the boundary Yang-Baxter equation for 19-vertex models known as Zamolodchikov-Fateev or $A_{1}^{(1)}$ model, Izergin-Korepin or $A_{2}^{(2)}$ model, sl(2|1) model and osp(2|1) model. We find that there is a general solution for $A_{1}^{(1)}$ and sl(2|1) models. In both models it is a complete K-matrix with three free parameters. For the $A_{2}^{(2)}$ and osp(2|1) models we find three general solutions, being two complete reflection K-matrices solutions and one incomplete reflection K-matrix solution with some null entries. In both models these solutions have two free parameters. Integrable spin-1 Hamiltonians with general boundary interactions are also presented. Several reduced solutions from these general solutions are presented in the appendices. Journal: Nucl. Phys. B 558 [PM] 637-667
Submitter: John Harnad Authors: J. Harnad (C.R.M., U. de Montreal and Concordia U.) Title: On the bilinear equations for Fredholm determinants appearing in random matrices Abstract: It is shown how the bilinear differential equations satisfied by Fredholm determinants of integral operators appearing as spectral distribution functions for random matrices may be deduced from the associated systems of nonautonomous Hamiltonian equations satisfied by auxiliary canonical phase space variables introduced by Tracy and Widom. The essential step is to recast the latter as isomonodromic deformation equations for families of rational covariant derivative operators on the Riemann sphere and interpret the Fredholm determinants as isomonodromic $\tau$-functions. Journal: J. Nonlinear Math. Phys., volume 9, no. 4 (2002) 530-550
Submitter: Runliang Lin Authors: Yunbo Zeng (1), Wen-Xiu Ma (2) ((1)Tsinghua University, Beijing, China, (2) City University of Hong Kong, China) Title: Families of quai-bi-Hamiltonian systems and separability Abstract: It is shown how to construct an infinite number of families of quasi-bi-Hamiltonian (QBH) systems by means of the constrained flows of soliton equations. Three explicit QBH structures are presented for the first three families of the constrained flows. The Nijenhuis coordinates defined by the Nijenhuis tensor for the corresponding families of QBH systems are proved to be exactly the same as the separated variables introduced by means of the Lax matrices for the constrained flows. Journal: None
Submitter: F. Nijhoff Authors: F.W. Nijhoff, N. Joshi, A. Hone Title: On the discrete and continuous Miura Chain associated with the Sixth Painlev\'e Equation Abstract: A Miura chain is a (closed) sequence of differential (or difference) equations that are related by Miura or B\"acklund transformations. We describe such a chain for the sixth Painlev\'e equation (\pvi), containing, apart from \pvi itself, a Schwarzian version as well as a second-order second-degree ordinary differential equation (ODE). As a byproduct we derive an auto-B\"acklund transformation, relating two copies of \pvi with different parameters. We also establish the analogous ordinary difference equations in the discrete counterpart of the chain. Such difference equations govern iterations of solutions of \pvi under B\"acklund transformations. Both discrete and continuous equations constitute a larger system which include partial difference equations, differential-difference equations and partial differential equations, all associated with the lattice Korteweg-de Vries equation subject to similarity constraints. Journal: None
Submitter: Sergei M. Sergeev Authors: Sergei M. Sergeev Title: On exact solution of a classical 3D integrable model Abstract: We investigate some classical evolution model in the discrete 2+1 space-time. A map, giving an one-step time evolution, may be derived as the compatibility condition for some systems of linear equations for a set of auxiliary linear variables. Dynamical variables for the evolution model are the coefficients of these systems of linear equations. Determinant of any system of linear equations is a polynomial of two numerical quasimomenta of the auxiliary linear variables. For one, this determinant is the generating functions of all integrals of motion for the evolution, and on the other hand it defines a high genus algebraic curve. The dependence of the dynamical variables on the space-time point (exact solution) may be expressed in terms of theta functions on the jacobian of this curve. This is the main result of our paper. Journal: J. Nonlinear Math. Phys. 7 (2000), no. 1, 57-72
Submitter: James D. E. Grant Authors: James D.E. Grant Title: Paraconformal Structures and Integrable Systems Abstract: We consider some natural connections which arise between right-flat (p, q) paraconformal structures and integrable systems. We find that such systems may be formulated in Lax form, with a "Lax p-tuple" of linear differential operators, depending a spectral parameter which lives in (q-1)-dimensional complex projective space. Generally, the differential operators contain partial derivatives with respect to the spectral parameter. Journal: None
Submitter: G. Tondo Authors: G. Falqui, F. Magri, G. Tondo Title: Reduction of bihamiltonian systems and separation of variables: an example from the Boussinesq hierarchy Abstract: We discuss the Boussinesq system with $t_5$ stationary, within a general framework for the analysis of stationary flows of n-Gel'fand-Dickey hierarchies. We show how a careful use of its bihamiltonian structure can be used to provide a set of separation coordinates for the corresponding Hamilton--Jacobi equations. Journal: None
Submitter: Yuri B. Suris Authors: Yuri B. Suris Title: r-matrices for relativistic deformations of integrable systems Abstract: We include the relativistic lattice KP hierarchy, introduced by Gibbons and Kupershmidt, into the $r$-matrix framework. An $r$-matrix account of the nonrelativistic lattice KP hierarchy is also provided for the reader's convenience. All relativistic constructions are regular one-parameter perturbations of the nonrelativistic ones. We derive in a simple way the linear Hamiltonian structure of the relativistic lattice KP, and find for the first time its quadratic Hamiltonian structure. Amasingly, the latter turns out to coincide with its nonrelativistic counterpart (a phenomenon, known previously only for the simplest case of the relativistic Toda lattice). Journal: J. Nonlinear Math. Phys. 6 (1999), no. 4, 411-447
Submitter: None Authors: Shigeki Matsutani Title: p-adic Difference-Difference Lotka-Volterra Equation and Ultra-Discrete Limit Abstract: In this article, we have studied the difference-difference Lotka-Volterra equations in p-adic number space and its p-adic valuation version. We pointed out that the structure of the space given by taking the ultra-discrete limit is the same as that of the $p$-adic valuation space. Journal: None
Submitter: S. Yu. Sakovich Authors: S. Yu. Sakovich Title: Integrability of the higher-order nonlinear Schroedinger equation revisited Abstract: Only the known integrable cases of the Kodama-Hasegawa higher-order nonlinear Schroedinger equation pass the Painleve test. Recent results of Ghosh and Nandy add no new integrable cases of this equation. Journal: None
Submitter: Nadja Kutz Authors: Tim Hoffmann, Johannes Kellendonk, Nadja Kutz and Nicolai Reshetikhin Title: Factorization dynamics and Coxeter-Toda lattices Abstract: It is shown that the factorization relation on simple Lie groups with standard Poisson Lie structure restricted to Coxeter symplectic leaves gives an integrable dynamical system. This system can be regarded as a discretization of the Toda flow. In case of $SL_n$ the integrals of the factorization dynamics are integrals of the relativistic Toda system. A substantial part of the paper is devoted to the study of symplectic leaves in simple complex Lie groups, its Borel subgroups and their doubles. Journal: Comm. Math. Phys. 212, Issue 2, 297-321 (2000)
Submitter: Peter Forrester Authors: M. Adler, P.J. Forrester, T. Nagao and P. van Moerbeke Title: Classical skew orthogonal polynomials and random matrices Abstract: Skew orthogonal polynomials arise in the calculation of the $n$-point distribution function for the eigenvalues of ensembles of random matrices with orthogonal or symplectic symmetry. In particular, the distribution functions are completely determined by a certain sum involving the skew orthogonal polynomials. In the cases that the eigenvalue probability density function involves a classical weight function, explicit formulas for the skew orthogonal polynomials are given in terms of related orthogonal polynomials, and the structure is used to give a closed form expression for the sum. This theory treates all classical cases on an equal footing, giving formulas applicable at once to the Hermite, Laguerre and Jacobi cases. Journal: None
Submitter: Tim Hoffmann Authors: Tim Hoffmann Title: On the equivalence of the discrete nonlinear Schr\"odinger equation and the discrete isotropic Heisenberg magnet Abstract: The equivalence of the discrete isotropic Heisenberg magnet (IHM) model and the discrete nonlinear Schr\"odinger equation (NLSE) given by Ablowitz and Ladik is shown. This is used to derive the equivalence of their discretization with the one by Izergin and Korepin. Moreover a doubly discrete IHM is presented that is equivalent to Ablowitz' and Ladiks doubly discrete NLSE. Journal: None
Submitter: Sudipta Nandy Authors: Sasanka Ghosh and Sudipta Nandy Title: A New Class of Optical Solitons Abstract: Existence of a new class of soliton solutions is shown for higher order nonlinear Schrodinger equation, describing thrid order dispersion, Kerr effect and stimulated Raman scattering. These new solutions have been obtaiened by invoking a group of nonlinear transformations acting on localised stable solutions. Stability of these solutions has been studied for different values of the arbitrary coefficients, involved in the recursion relation and consequently, different values of coefficient lead to different transmission rates for almost same input power. Another series solution containing even powers of localised stable solution is shown to exist for higher order nonlinear Schrodinger equation. Journal: None
Submitter: Alexander Sorin Authors: F. Delduc, L. Gallot and A. Sorin Title: N=2 local and N=4 nonlocal reductions of supersymmetric KP hierarchy in N=2 superspace Abstract: A N=4 supersymmetric matrix KP hierarchy is proposed and a wide class of its reductions which are characterized by a finite number of fields are described. This class includes the one-dimensional reduction of the two-dimensional N=(2|2) superconformal Toda lattice hierarchy possessing the N=4 supersymmetry -- the N=4 Toda chain hierarchy -- which may be relevant in the construction of supersymmetric matrix models. The Lax pair representations of the bosonic and fermionic flows, corresponding local and nonlocal Hamiltonians, finite and infinite discrete symmetries, the first two Hamiltonian structures and the recursion operator connecting all evolution equations and the Hamiltonian structures of the N=4 Toda chain hierarchy are constructed in explicit form. Its secondary reduction to the N=2 supersymmetric alpha=-2 KdV hierarchy is discussed. Journal: Nucl.Phys. B558 (1999) 545-572
Submitter: Atalay Karasu Authors: Atalay Karasu Title: On A Recently Proposed Relation Between oHS and Ito Systems Abstract: The bi-Hamiltonian structure of original Hirota-Satsuma system proposed by Roy based on a modification of the bi-Hamiltonian structure of Ito system is incorrect. Journal: None
Submitter: Marcio J. Martins Authors: M.J. Martins and X.W. Guan Title: Integrable supersymmetric correlated electron chain with open boundaries Abstract: We construct an extended Hubbard model with open boundaries from a $R$-matrix based on the $U_q[Osp(2|2)]$ superalgebra. We study the reflection equation and find two classes of diagonal solutions. The corresponding one-dimensional open Hamiltonians are diagonalized by means of the Bethe ansatz approach. Journal: Nucl. Phys. B 562 (1999) 433-444
Submitter: Hendry Izaac Elim Authors: Hendry I. Elim Title: New Integrable Coupled Nonlinear Schrodinger Equations Abstract: Two types of integrable coupled nonlinear Schrodinger (NLS) equations are derived by using Zakharov-Shabat (ZS) dressing method.The Lax pairs for the coupled NLS equations are also investigated using the ZS dressing method. These give new types of the integrable coupled NLS equations with certain additional terms. Then, the exact solutions of the new types are obtained. We find that the solution of these new types do not always produce a soliton solution even they are the kind of the integrable NLS equations. Journal: None
Submitter: Peter Forrester Authors: P.J. Forrester and E.M. Rains Title: Inter-relationships between orthogonal, unitary and symplectic matrix ensembles Abstract: We consider the following problem: When do alternate eigenvalues taken from a matrix ensemble themselves form a matrix ensemble? More precisely, we classify all weight functions for which alternate eigenvalues from the corresponding orthogonal ensemble form a symplectic ensemble, and similarly classify those weights for which alternate eigenvalues from a union of two orthogonal ensembles forms a unitary ensemble. Also considered are the $k$-point distributions for the decimated orthogonal ensembles. Journal: None
Submitter: Fritz Gesztesy Authors: Fritz Gesztesy Title: Integrable Systems in the Infinite Genus Limit Abstract: We provide an elementary approach to integrable systems associated with hyperelliptic curves of infinite genus. In particular, we explore the extent to which the classical Burchnall-Chaundy theory generalizes in the infinite genus limit, and systematically study the effect of Darboux transformations for the KdV hierarchy on such infinite genus curves. Our approach applies to complex-valued periodic solutions of the KdV hierarchy and naturally identifies the Riemann surface familiar from standard Floquet theoretic considerations with a limit of Burchnall-Chaundy curves. Journal: None
Submitter: Jon Links Authors: Jon Links (U. of Queensland) Title: A construction for R-matrices without difference property in the spectral parameter Abstract: A new construction is given for obtaining R-matrices which solve the McGuire-Yang-Baxter equation in such a way that the spectral parameters do not possess the difference property. A discussion of the derivation of the supersymmetric U model is given in this context such that applied chemical potential and magnetic field terms can be coupled arbitrarily. As a limiting case the Bariev model is obtained. Journal: Phys. Lett. A 265 (2000) 194-206
Submitter: Dmitry Pelinovsky Authors: Dmitry E. Pelinovsky and Catherine Sulem Title: Spectral decomposition for the Dirac system associated to the DSII equation Abstract: A new (scalar) spectral decomposition is found for the Dirac system in two dimensions associated to the focusing Davey--Stewartson II (DSII) equation. Discrete spectrum in the spectral problem corresponds to eigenvalues embedded into a two-dimensional essential spectrum. We show that these embedded eigenvalues are structurally unstable under small variations of the initial data. This instability leads to the decay of localized initial data into continuous wave packets prescribed by the nonlinear dynamics of the DSII equation. Journal: None
Submitter: Adam Doliwa Authors: Adam Doliwa and Paolo Maria Santini Title: The symmetric, D-invariant and Egorov reductions of the quadrilateral lattice Abstract: We present a detailed study of the geometric and algebraic properties of the multidimensional quadrilateral lattice (a lattice whose elementary quadrilaterals are planar; the discrete analogue of a conjugate net) and of its basic reductions. To make this study, we introduce the notions of forward and backward data, which allow us to give a geometric meaning to the tau-function of the lattice, defined as the potential connecting these data. Together with the known circular lattice (a lattice whose elementary quadrilaterals can be inscribed in circles; the discrete analogue of an orthogonal conjugate net) we introduce and study two other basic reductions of the quadrilateral lattice: the symmetric lattice, for which the forward and backward data coincide, and the D-invariant lattice, characterized by the invariance of a certain natural frame along the main diagonal. We finally discuss the Egorov lattice, which is, at the same time, symmetric, circular and D-invariant. The integrability properties of all these lattices are established using geometric, algebraic and analytic means; in particular we present a D-bar formalism to construct large classes of such lattices. We also discuss quadrilateral hyperplane lattices and the interplay between quadrilateral point and hyperplane lattices in all the above reductions. Journal: None
Submitter: Adam Doliwa Authors: Adam Doliwa Title: Lattice geometry of the Hirota equation Abstract: Geometric interpretation of the Hirota equation is presented as equation describing the Laplace sequence of two-dimensional quadrilateral lattices. Different forms of the equation are given together with their geometric interpretation: (i) the discrete coupled Volterra system for the coefficients of the Laplace equation, (ii) the gauge invariant form of the Hirota equation for projective invariants of the Laplace sequence, (iii) the discrete Toda system for the rotation coefficients, (iv) the original form of the Hirota equation for the tau-function of the quadrilateral lattice. Journal: None
Submitter: Adam Doliwa Authors: Adam Doliwa and Paolo Maria Santini Title: Integrable Discrete Geometry: the Quadrilateral Lattice, its Transformations and Reductions Abstract: We review recent results on Integrable Discrete Geometry. It turns out that most of the known (continuous and/or discrete) integrable systems are particular symmetries of the quadrilateral lattice, a multidimensional lattice characterized by the planarity of its elementary quadrilaterals. Therefore the linear property of planarity seems to be a basic geometric property underlying integrability. We present the geometric meaning of its tau-function, as the potential connecting its forward and backward data. We present the theory of transformations of the quadrilateral lattice, which is based on the discrete analogue of the theory of rectilinear congruences. In particular, we discuss the discrete analogues of the Laplace, Combescure, Levy, radial and fundamental transformations and their interrelations. We also show how the sequence of Laplace transformations of a quadrilateral surface is described by the discrete Toda system. We finally show that these classical transformations are strictly related to the basic operators associated with the quantum field theoretical formulation of the multicomponent Kadomtsev-Petviashvilii hierarchy. We review the properties of quadrilateral hyperplane lattices, which play an interesting role in the reduction theory, when the introduction of additional geometric structures allows to establish a connection between point and hyperplane lattices. We present and fully characterize some geometrically distinguished reductions of the quadrilateral lattice, like the symmetric, circular and Egorov lattices; we review also basic geometric results of the theory of quadrilateral lattices in quadrics, and the corresponding analogue of the Ribaucour reduction of the fundamental transformation. Journal: None
Submitter: F. Nijhoff Authors: F.W. Nijhoff (University of Leeds) Title: Discrete Dubrovin Equations and Separation of Variables for Discrete Systems Abstract: A universal system of difference equations associated with a hyperelliptic curve is derived constituting the discrete analogue of the Dubrovin equations arising in the theory of finite-gap integration. The parametrisation of the solutions in terms of Abelian functions of Kleinian type (i.e. the higher-genus analogues of the Weierstrass elliptic functions) is discussed as well as the connections with the method of separation of variables. Journal: None
Submitter: Nobuhiko Shinzawa Authors: Nobuhiko Shinzawa Title: Symmetric Linear Backlund Transformation for Discrete BKP and DKP equation Abstract: Proper lattices for the discrete BKP and the discrete DKP equaitons are determined. Linear B\"acklund transformation equations for the discrete BKP and the DKP equations are constructed, which possesses the lattice symmetries and generate auto-B\"acklund transformations Journal: None
Submitter: Fritz Gesztesy Authors: F. Gesztesy, C. K. R. T. Jones, Y. Latushkin, and M. Stanislavova Title: A Spectral Mapping Theorem and Invariant Manifolds for Nonlinear Schr\"odinger Equations Abstract: A spectral mapping theorem is proved that resolves a key problem in applying invariant manifold theorems to nonlinear Schr\" odinger type equations. The theorem is applied to the operator that arises as the linearization of the equation around a standing wave solution. We cast the problem in the context of space-dependent nonlinearities that arise in optical waveguide problems. The result is, however, more generally applicable including to equations in higher dimensions and even systems. The consequence is that stable, unstable, and center manifolds exist in the neighborhood of a (stable or unstable) standing wave, such as a waveguide mode, under simple and commonly verifiable spectral conditions. Journal: None
Submitter: Takayuki Tsuchida Authors: Takayuki Tsuchida, Miki Wadati (University of Tokyo) Title: Multi-Field Integrable Systems Related to WKI-Type Eigenvalue Problems Abstract: Higher flows of the Heisenberg ferromagnet equation and the Wadati-Konno-Ichikawa equation are generalized into multi-component systems on the basis of the Lax formulation. It is shown that there is a correspondence between the multi-component systems through a gauge transformation. An integrable semi-discretization of the multi-component higher Heisenberg ferromagnet system is obtained. Journal: J. Phys. Soc. Jpn. 68 (1999) 2241-2245
Submitter: Liu Qing Ping Authors: Q.P. Liu Title: Miura Map between Lattice KP and its Modification is Canonical Abstract: We consider the Miura map between the lattice KP hierarchy and the lattice modified KP hierarchy and prove that the map is canonical not only between the first Hamiltonian structures, but also between the second Hamiltonian structures. Journal: None
Submitter: Goro Hatayama Authors: Goro Hatayama, Atsuo Kuniba, and Taichiro Takagi Title: Soliton Cellular Automata Associated With Crystal Bases Abstract: We introduce a class of cellular automata associated with crystals of irreducible finite dimensional representations of quantum affine algebras U'_q(\hat{\geh}_n). They have solitons labeled by crystals of the smaller algebra U'_q(\hat{\geh}_{n-1}). We prove stable propagation of one soliton for \hat{\geh}_n = A^{(2)}_{2n-1}, A^{(2)}_{2n}, B^{(1)}_n, C^{(1)}_n, D^{(1)}_n and D^{(2)}_{n+1}. For \gh_n = C^{(1)}_n, we also prove that the scattering matrices of two solitons coincide with the combinatorial R matrices of U'_q(C^{(1)}_{n-1})-crystals. Journal: Nuclear Physics B577[PM](2000) 619-645
Submitter: Olaf Lechtenfeld Authors: Olaf Lechtenfeld and Alexander Sorin Title: Supersymmetric KP hierarchy in N=1 superspace and its N=2 reductions Abstract: A wide class of N=2 reductions of the supersymmetric KP hierarchy in N=1 superspace is described. This class includes a new N=2 supersymmetric generalization of the Toda chain hierarchy. The Lax pair representations of the bosonic and fermionic flows, local and nonlocal Hamiltonians, finite and infinite discrete symmetries, first two Hamiltonian structures and the recursion operator of this hierarchy are constructed. Its secondary reduction to new N=2 supersymmetric modified KdV hierarchy is discussed. Journal: Nucl.Phys. B566 (2000) 489-510
Submitter: Ziad Maassarani Authors: Z. Maassarani (University of Virginia) Title: Non-additive fusion, Hubbard models and non-locality Abstract: In the framework of quantum groups and additive R-matrices, the fusion procedure allows to construct higher-dimensional solutions of the Yang-Baxter equation. These solutions lead to integrable one-dimensional spin-chain Hamiltonians. Here fusion is shown to generalize naturally to non-additive R-matrices, which therefore do not have a quantum group symmetry. This method is then applied to the generalized Hubbard models. Although the resulting integrable models are not as simple as the starting ones, the general structure is that of two spin-(s times s') sl(2) models coupled at the free-fermion point. An important issue is the probable lack of regular points which give local Hamiltonians. This problem is related to the existence of second order zeroes in the unitarity equation, and arises for the XX models of higher spins, the building blocks of the Hubbard models. A possible connection between some Lax operators L and R-matrices is noted. Journal: J. Phys. A 32 (1999) 8691-8703
Submitter: V. Kuznetsov Authors: V.B.Kuznetsov, M.Salerno and E.K.Sklyanin Title: Quantum Backlund transformation for the integrable DST model Abstract: For the integrable case of the discrete self-trapping (DST) model we construct a Backlund transformation. The dual Lax matrix and the corresponding dual Backlund transformation are also found and studied. The quantum analog of the Backlund transformation (Q-operator) is constructed as the trace of a monodromy matrix with an infinite-dimensional auxiliary space. We present the Q-operator as an explicit integral operator as well as describe its action on the monomial basis. As a result we obtain a family of integral equations for multivariable polynomial eigenfunctions of the quantum integrable DST model. These eigenfunctions are special functions of the Heun class which is beyond the hypergeometric class. The found integral equations are new and they shall provide a basis for efficient analytical and numerical studies of such complicated functions. Journal: J.Phys.A33:171-189,2000
Submitter: Konstantin Selivanov Authors: K.G. Selivanov (ITEP, Moscow) Title: Classical Solutions Generating Tree Form-Factors in Yang-Mills, Sin(h)-Gordon and Gravity Abstract: Classical solutions generating tree form-factors are defined and constructed in various models. Journal: None
Submitter: Alexander Mikhailov Authors: A. V. Mikhailov, V. V. Sokolov Title: Integrable ODEs on Associative Algebras Abstract: In this paper we give definitions of basic concepts such as symmetries, first integrals, Hamiltonian and recursion operators suitable for ordinary differential equations on associative algebras, and in particular for matrix differential equations. We choose existence of hierarchies of first integrals and/or symmetries as a criterion for integrability and justify it by examples. Using our componentless approach we have solved a number of classification problems for integrable equations on free associative algebras. Also, in the simplest case, we have listed all possible Hamiltonian operators of low order. Journal: None
Submitter: Wen-Xiu Ma Authors: Wen-Xiu Ma and Ruguang Zhou Title: A Coupled AKNS-Kaup-Newell Soliton Hierarchy Abstract: A coupled AKNS-Kaup-Newell hierarchy of systems of soliton equations is proposed in terms of hereditary symmetry operators resulted from Hamiltonian pairs. Zero curvature representations and tri-Hamiltonian structures are established for all coupled AKNS-Kaup-Newell systems in the hierarchy. Therefore all systems have infinitely many commuting symmetries and conservation laws. Two reductions of the systems lead to the AKNS hierarchy and the Kaup-Newell hierarchy, and thus those two soliton hierarchies also possess tri-Hamiltonian structures. Journal: None
Submitter: Takayuki Tsuchida Authors: Takayuki Tsuchida, Miki Wadati (University of Tokyo) Title: Complete integrability of derivative nonlinear Schr\"{o}dinger-type equations Abstract: We study matrix generalizations of derivative nonlinear Schr\"{o}dinger-type equations, which were shown by Olver and Sokolov to possess a higher symmetry. We prove that two of them are `C-integrable' and the rest of them are `S-integrable' in Calogero's terminology. Journal: Inverse Problems 15 (1999) 1363-1373
Submitter: Kenji Kajiwara Authors: Kenji Kajiwara(Doshisha Univ.), Tetsu Masuda(Doshisha Univ.), Masatoshi Noumi(Kobe Univ.), Yasuhiro Ohta(Hiroshima Univ.), Yasuhiko Yamada(Kobe Univ.) Title: Determinant Formulas for the Toda and Discrete Toda Equations Abstract: Determinant formulas for the general solutions of the Toda and discrete Toda equations are presented. Application to the $\tau$ functions for the Painlev\'e equations is also discussed. Journal: None
Submitter: Ladislav Hlavaty Authors: L. Hlavaty Title: Towards the Lax formulation of SU(2) principal models with nonconstant metric Abstract: The equations that define the Lax pairs for generalized principal chiral models can be solved for any constant nondegenerate bilinear form on SU(2). Necessary conditions for the nonconstant metric on SU(2) that define the integrable models are given. Journal: None
Submitter: Takeo Kojima Authors: H. Furutsu, T. Kojima, and Y.-H. Quano Title: Type II vertex operators for the $A_{n-1}^{(1)}$ face model Abstract: Presented is a free boson representation of the type II vertex operators for the $A_{n-1}^{(1)}$ face model. Using the bosonization, we derive some properties of the type II vertex operators, such as commutation, inversion and duality relations. Journal: Int.J.Mod.Phys. A15 (2000) 1533-1556
Submitter: Wen-Xiu Ma Authors: Wen-Xiu Ma and Si-Ming Zhu Title: Non-symmetry constraints of the AKNS system yielding integrable Hamiltonian systems Abstract: This paper aims to show that there exist non-symmetry constraints which yield integrable Hamiltonian systems through nonlinearization of spectral problems of soliton systems, like symmetry constraints. Taking the AKNS spectral problem as an illustrative example, a class of such non-symmetry constraints is introduced for the AKNS system, along with two-dimensional integrable Hamiltonian systems generated from the AKNS spectral problem. Journal: None
Submitter: Alexander I. Bobenko Authors: Sergey I. Agafonov, Alexander I. Bobenko Title: Discrete Z^a and Painleve equations Abstract: A discrete analogue of the holomorphic map z^a is studied. It is given by a Schramm's circle pattern with the combinatorics of the square grid. It is shown that the corresponding immersed circle patterns lead to special separatrix solutions of a discrete Painleve equation. Global properties of these solutions, as well as of the discrete $z^a$ are established. Journal: International Math. Research Notices 2000:4 165-193
Submitter: Metin Gurses Authors: Metin Gurses (Bilkent University), Atalay Karasu (METU), and Vladimir Sokolov (Landau Institue) Title: On Construction of Recursion Operators From Lax Representation Abstract: In this work we develop a general procedure for constructing the recursion operators fro non-linear integrable equations admitting Lax representation. Svereal new examples are given. In particular we find the recursion operators for some KdV-type of integrable equations. Journal: None
Submitter: Andrey Tsyganov User Authors: Andrey Tsiganov Title: On integrable deformations of the spherical top Abstract: The motion on the sphere $S^2$ with the potential $V= (x_1x_2x_3)^{-2/3}$ is considered. The Lax representation and the linearisation procedure for this two-dimensional integrable system are discussed. Journal: J. Phys. A, Math. Gen. 32, No.47, 8355-8363, (1999)
Submitter: Dmitry Demskoy Authors: D.K.Demskoy, A.G.Meshkov Title: New integrable string-like fields in 1+1 dimensions Abstract: The symmetry classification method is applied to the string-like scalar fields in two-dimensional space-time. When the configurational space is three-dimensional and reducible we present the complete list of the systems admiting higher polynomial symmetries of the 3rd, 4th and 5th-order. Journal: None
Submitter: Andrey V. Tsiganov Authors: Andrey Tsiganov Title: Canonical transformations of the extended phase space, Toda lattices and Stackel family of integrable systems Abstract: We consider compositions of the transformations of the time variable and canonical transformations of the other coordinates, which map completely integrable system into other completely integrable system. Change of the time gives rise to transformations of the integrals of motion and the Lax pairs, transformations of the corresponding spectral curves and R-matrices. As an example, we consider canonical transformations of the extended phase space for the Toda lattices and the Stackel systems. Journal: J. Phys. A, Math. Gen. 33, No.22, 4169-4182, (2000)
Submitter: Hans Jacobus Wospakrik Authors: Hans J. Wospakrik and Freddy P. Zen Title: CPT Symmetries and the Backlund Transformations Abstract: We show that the auto-Backlund transformations of the sine-Gordon, Korteweg-deVries, nonlinear Schrodinger, and Ernst equations are related to their respective CPT symmetries. This is shown by applying the CPT symmetries of these equations to the Riccati equations of the corresponding pseudopotential functions where the fields are allowed to transform into new solutions while the pseudopotential functions and the Backlund parameter are held fixed. Journal: None
Submitter: Andrey K. Svinin Authors: A.K. Svinin Title: Lie point symmetries of integrable evolution equations and invariant solutions Abstract: An integrable hierarchies connected with linear stationary Schr\"odinger equation with energy dependent potentials (in general case) are considered. Galilei-like and scaling invariance transformations are constructed. A symmetry method is applied to construct invariant solutions. Journal: None
Submitter: Yuri B. Suris Authors: Yuri B. Suris (TU Berlin) Title: The motion of a rigid body in a quadratic potential: an integrable discretization Abstract: The motion of a rigid body in a quadratic potential is an important example of an integrable Hamiltonian system on a dual to a semidirect product Lie algebra so(n) x Symm(n). We give a Lagrangian derivation of the corresponding equations of motion, and introduce a discrete time analog of this system. The construction is based on the discrete time Lagrangian mechanics on Lie groups, accompanied with the discrete time Lagrangian reduction. The resulting multi-valued map (correspondence) on the dual to so(n) x Symm(n) is Poisson with respect to the Lie-Poisson bracket, and is also completely integrable. We find a Lax representation based on matrix factorisations, in the spirit of Veselov-Moser. Journal: Intern. Math. Research Notices, 2000, No 12, p.643-663.
Submitter: Pierre van Moerbeke Authors: M. Adler, T. Shiota and P. van Moerbeke Title: Pfaff tau-functions Abstract: Consider the evolution $$ \frac{\pl m_\iy}{\pl t_n}=\Lb^n m_\iy, \frac{\pl m_\iy}{\pl s_n}=-m_\iy(\Lb^\top)^n, $$ on bi- or semi-infinite matrices $m_\iy=m_\iy(t,s)$, with skew-symmetric initial data $m_{\iy}(0,0)$. Then, $m_\iy(t,-t)$ is skew-symmetric, and so the determinants of the successive "upper-left corners" vanish or are squares of Pfaffians. In this paper, we investigate the rich nature of these Pfaffians, as functions of t. This problem is motivated by questions concerning the spectrum of symmetric and symplectic random matrix ensembles. Journal: None
Submitter: David Fairlie Authors: D.B. Fairlie and A.N. Leznov Title: The Complex Bateman Equation Abstract: The general solution to the Complex Bateman equation is constructed. It is given in implicit form in terms of a functional relationship for the unknown function. The known solution of the usual Bateman equation is recovered as a special case. Journal: None
Submitter: David Fairlie Authors: D.B. Fairlie and A.N. Leznov Title: The General Solution of the Complex Monge-Amp\`ere Equation in two dimensional space Abstract: The general solution to the Complex Monge-Amp\`ere equation in a two dimensional space is constructed. Journal: None
Submitter: David Fairlie Authors: D.B. Fairlie and A.N. Leznov Title: The Complex Bateman Equation in a space of arbitrary dimension Abstract: A general solution to the Complex Bateman equation in a space of arbitrary dimensions is constructed. Journal: None
Submitter: David Fairlie Authors: D.B. Fairlie and A.N. Leznov Title: The General Solution of the Complex Monge-Amp\`ere Equation in a space of arbitrary dimension Abstract: A general solution to the Complex Monge-Amp\`ere equation in a space of arbitrary dimensions is constructed. Journal: None
Submitter: Adam Doliwa Authors: Adam Doliwa (Warsaw University) Title: Discrete asymptotic nets and W-congruences in Plucker line geometry Abstract: The asymptotic lattices and their transformations are studied within the line geometry approach. It is shown that the discrete asymptotic nets are represented by isotropic congruences in the Plucker quadric. On the basis of the Lelieuvre-type representation of asymptotic lattices and of the discrete analog of the Moutard transformation, it is constructed the discrete analog of the W-congruences, which provide the Darboux-Backlund type transformation of asymptotic lattices.The permutability theorems for the discrete Moutard transformation and for the corresponding transformation of asymptotic lattices are established as well. Moreover, it is proven that the discrete W-congruences are represented by quadrilateral lattices in the quadric of Plucker. These results generalize to a discrete level the classical line-geometric approach to asymptotic nets and W-congruences, and incorporate the theory of asymptotic lattices into more general theory of quadrilateral lattices and their reductions. Journal: J. Geom. Phys. 39 (2001) 9-29
Submitter: Liu Qing Ping Authors: Q. P. Liu, Manuel Manas Title: Darboux Transformation for Supersymmetric KP Hierarchies Abstract: We construct Darboux transformations for the super-symmetric KP hierarchies of Manin--Radul and Jacobian types. We also consider the binary Darboux transformation for the hierarchies. The iterations of both type of Darboux transformations are briefly discussed. Journal: Phys.Lett.B485:293-300,2000
Submitter: Pilar G. Estevez Authors: P. G. Estevez and G. A. Hernaez (Universidad de Salamanca, Spain) Title: Darboux transformations for a Bogoyavlenskii equation in 2+1 dimensions Abstract: We use the singular manifold method to obtain the Lax pair, Darboux transformations and soliton solutions for a (2+1) dimensional integrable equation. Journal: None
Submitter: Roman Paunov Authors: H. Belich, G. Cuba and R. Paunov Title: Surfaces of Constant negative Scalar Curvature and the Correpondence between the Liouvulle and the sine-Gordon Equations Abstract: By studying the {\it internal} Riemannian geometry of the surfaces of constant negative scalar curvature, we obtain a natural map between the Liouville, and the sine-Gordon equations. First, considering isometric immersions into the Lobachevskian plane, we obtain an uniform expression for the general (locally defined) solution of both the equations. Second, we prove that there is a Lie-B\"acklund transformation interpolating between Liouville and sine-Gordon. Third, we use isometric immersions into the Lobachevskian plane to describe sine-Gordon N-solitons explicitly. Journal: None
Submitter: Kazuyasu Shigemoto Authors: M.Horibe and K.Shigemoto Title: The Structure of the Bazhanov-Baxter Model and a New Solution of the Tetrahedron Equation Abstract: We clarify the structure of the Bazhanov-Baxter model of the 3-dim N-state integrable model. There are two essential points, i) the cubic symmetries, and ii) the spherical trigonometry parametrization, to understand the structure of this model. We propose two approaches to find a candidate as a solution of the tetrahedron equation, and we find a new solution. Journal: Progr. Theor. Phys. 102 (1999), 221-236
Submitter: Vladimir Gerdjikov Authors: V. S. Gerdjikov (Institute for Nuclear Research and Nuclear Energy, Bulg. Acad. of Sci., Sofia,Bulgaria), E. G. Evstatiev (Department of Physics, University of Texas at Austin, Austin, Texas, USA), R. I. Ivanov (Department of Mathematical Physics National University of Ireland - Galway, Galway, Ireland) Title: The complex Toda chains and the simple Lie algebras - solutions and large time asymptotics -- II Abstract: We propose a compact and explicit expression for the solutions of the complex Toda chains related to the classical series of simple Lie algebras g. The solutions are parametrized by a minimal set of scattering data for the corresponding Lax matrix. They are expressed as sums over the weight systems of the fundamental representations of g and are explicitly covariant under the corresponding Weyl group action. In deriving these results we start from the Moser formula for the A_r series and obtain the results for the other classical series of Lie algebras by imposing appropriate involutions on the scattering data. Thus we also show how Moser's solution goes into the one of Olshanetsky and Perelomov. The results for the large-time asymptotics of the A_r -CTC solutions are extended to the other classical series B_r - D_r. We exhibit also some `irregular' solutions for the D_{2n+1} algebras whose asymptotic regimes at t ->\pm\infty are qualitatively different. Interesting examples of bounded and periodic solutions are presented and the relations between the solutions for the algebras D_4, B_3 and G_2 $ are analyzed. Journal: None
Submitter: Vladimir Marikhin Authors: M. Boiti, V.G. Marikhin, F. Pempinelli, A.B. Shabat Title: Self-similar solutions of NLS-type dynamical systems Abstract: We study self-similar solutions of NLS-type dynamical systems. Lagrangian approach is used to show that they can be reduced to three canonical forms, which are related by Miura transformations. The fourth Painleve equation (PIV) is central in our consideration - it connects Heisenberg model, Volterra model and Toda model to each other. The connection between the rational solutions of PIV and Coulomb gas in a parabolic potential is established. We discuss also the possibility to obtain an exact solution for optical soliton i.e. of the NLS equation with time-dependent dispersion. Journal: None
Submitter: Igor Loutsenko Authors: I.Loutsenko, V.Spiridonov Title: Self-similarity in Spectral Problems and q-special Functions Abstract: Similarity symmetries of the factorization chains for one-dimensional differential and finite-difference Schr\"odinger equations are discussed. Properties of the potentials defined by self-similar reductions of these chains are reviewed. In particular, their algebraic structure, relations to $q$-special functions, infinite soliton systems, supersymmetry, coherent states, orthogonal polynomials, one-dimensional Ising chains and random matrices are outlined. Journal: None
Submitter: Saburo Kakei Authors: Saburo Kakei Title: Orthogonal and symplectic matrix integrals and coupled KP hierarchy Abstract: Orthogonal and symplectic matrix integrals are investigated. It is shown that the matrix integrals can be considered as a $\tau$-function of the coupled KP hierarchy, whose solution can be expressed in terms of pfaffians. Journal: J.Phys.Soc.Jap. 68 (1999) 2875-2877
Submitter: Saburo Kakei Authors: Saburo Kakei Title: Dressing method and the coupled KP hierarchy Abstract: The coupled KP hierarchy, introduced by Hirota and Ohta, are investigated by using the dressing method. It is shown that the coupled KP hierarchy can be reformulated as a reduced case of the 2-component KP hierarchy. Journal: None
Submitter: Krzysztof Marciniak Authors: Stefan Rauch-Wojciechowski, Krzysztof Marciniak, Hans Lundmark Title: Quasi-Lagrangian Systems of Newton Equations Abstract: Systems of Newton equations of the form $\ddot{q}=-{1/2}A^{-1}(q)\nabla k$ with an integral of motion quadratic in velocities are studied. These equations generalize the potential case (when A=I, the identity matrix) and they admit a curious quasi-Lagrangian formulation which differs from the standard Lagrange equations by the plus sign between terms. A theory of such quasi-Lagrangian Newton (qLN) systems having two functionally independent integrals of motion is developed with focus on two-dimensional systems. Such systems admit a bi-Hamiltonian formulation and are proved to be completely integrable by embedding into five-dimensional integrable systems. They are characterized by a linear, second-order PDE which we call the fundamental equation. Fundamental equations are classified through linear pencils of matrices associated with qLN systems. The theory is illustrated by two classes of systems: separable potential systems and driven systems. New separation variables for driven systems are found. These variables are based on sets of non-confocal conics. An effective criterion for existence of a qLN formulation of a given system is formulated and applied to dynamical systems of the Henon-Heiles type. Journal: None
Submitter: Andrew Hone Authors: Frank Nijhoff (University of Leeds), Andrew Hone and Nalini Joshi (University of Adelaide) Title: On a Schwarzian PDE associated with the KdV Hierarchy Abstract: We present a novel integrable non-autonomous partial differential equation of the Schwarzian type, i.e. invariant under M\"obius transformations, that is related to the Korteweg-de Vries hierarchy. In fact, this PDE can be considered as the generating equation for the entire hierarchy of Schwarzian KdV equations. We present its Lax pair, establish its connection with the SKdV hierarchy, its Miura relations to similar generating PDEs for the modified and regular KdV hierarchies and its Lagrangian structure. Finally we demonstrate that its similarity reductions lead to the {\it full} Painlev\'e VI equation, i.e. with four arbitary parameters. Journal: None
Submitter: Sergei Sakovich Authors: Sergei Sakovich Title: On two aspects of the Painleve analysis Abstract: We use the Calogero equation to illustrate the following two aspects of the Painleve analysis of nonlinear PDEs. First, if a nonlinear equation passes the Painleve test for integrability, the singular expansions of its solutions around characteristic hypersurfaces can be neither single-valued functions of independent variables nor single-valued functionals of data. Second, if the truncation of singular expansions of solutions is consistent, the truncation not necessarily leads to the simplest, or elementary, auto-Backlund transformation related to the Lax pair. Journal: Int. J. Analysis 2013 (2013) 172813 (5 pages)