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M. Olshanetsky

Publications and source records attributed to M. Olshanetsky.

At least 37 records · Page 2Linked to original sources

Characteristic Classes of SL(N)-Bundles and Quantum Dynamical Elliptic R-Matrices

We discuss quantum dynamical elliptic R-matrices related to arbitrary complex simple Lie group G. They generalize the known vertex and dynamical R-matrices and play an intermediate role between these two types. The R-matrices are defined by the corresponding characteristic classes describing the underlying vector bundles. The latter are related to elements of the center Z(G) of G. While the known dynamical R-matrices are related to the bundles with trivial characteristic classes, the Baxter-Belavin-Drinfeld-Sklyanin vertex R-matrix corresponds to the generator of the center Z_N of SL(N). We construct the R-matrices related to SL(N)- bundles with an arbitrary characteristic class explicitly and discuss the corresponding IRF models.

math-ph↗

Characteristic Classes and Integrable Systems. General Construction

We consider topologically non-trivial Higgs bundles over elliptic curves with marked points and construct corresponding integrable systems. In the case of one marked point we call them the modified Calogero-Moser systems (MCM systems). Their phase space has the same dimension as the phase space of the standard CM systems with spin, but less number of particles and greater number of spin variables. Topology of the holomorphic bundles are defined by their characteristic classes. Such bundles occur if G has a non-trivial center, i.e. classical simply-connected groups, $E_6$ and $E_7$. We define the conformal version CG of G - an analog of GL(N) for SL(N), and relate the characteristic classes with degrees of CG-bundles. Starting with these bundles we construct Lax operators, quadratic Hamiltonians, define the phase spaces and the Poisson structure using dynamical r-matrices. To describe the systems we use a special basis in the Lie algebras that generalizes the basis of t'Hooft matrices for sl(N). We find that the MCM systems contain the standard CM systems related to some (unbroken) subalgebras. The configuration space of the CM particles is the moduli space of the holomorphic bundles with non-trivial characteristic classes.

math-ph↗

Characteristic Classes and Integrable Systems for Simple Lie Groups

This paper is a continuation of our previous paper \cite{LOSZ}. For simple complex Lie groups with non-trivial center, i.e. classical simply-connected groups, $E_6$ and $E_7$ we consider elliptic Modified Calogero-Moser systems corresponding to the Higgs bundles with an arbitrary characteristic class. These systems are generalization of the classical Calogero-Moser (CM) systems related to a simple Lie groups and contain CM systems related to some (unbroken) subalgebras. For all algebras we construct a special basis, corresponding to non-trivial characteristic classes, the explicit forms of Lax operators and Hamiltonians.

math-ph↗

Three lectures on classical integrable systems and gauge field theories

In these lectures I consider the Hitchin integrable systems and their relations with the self-duality equations and the twisted super-symmetric Yang-Mills theory in four dimension follow Hitchin and Kapustin-Witten. I define the Symplectic Hecke correspondence between different integrable systems. As an example I consider Elliptic Calogero-Moser system and integrable Euler-Arnold top on coadjoint orbits of the group GL(N,C) and explain the Symplectic Hecke correspondence for these systems.

hep-th↗

Lie Algebroids and generalized projective structures on Riemann surfaces

The space of generalized projective structures on a Riemann surface $Σ$ of genus g with n marked points is the affine space over the cotangent bundle to the space of SL(N)-opers. It is a phase space of $W_N$-gravity on $Σ\times\mathbb{R}$. This space is a generalization of the space of projective structures on the Riemann surface. We define the moduli space of $W_N$-gravity as a symplectic quotient with respect to the canonical action of a special class of Lie algebroids. This moduli space describes in particular the moduli space of deformations of complex structures on the Riemann surface by differential operators of finite order, or equivalently, by a quotient space of Volterra operators. We call these algebroids the Adler-Gelfand-Dikii (AGD) algebroids, because they are constructed by means of AGD bivector on the space of opers restricted on a circle. The AGD-algebroids are particular case of Lie algebroids related to a Poisson sigma-model. The moduli space of the generalized projective structure can be described by cohomology of a BRST-complex.

math.QA↗

Quadratic algebras related to elliptic curves

We construct quadratic finite-dimensional Poisson algebras and their quantum versions related to rank N and degree one vector bundles over elliptic curves with n marked points. The algebras are parameterized by the moduli of curves. For N=2 and n=1 they coincide with the Sklyanin algebras. We prove that the Poisson structure is compatible with the Lie-Poisson structure on the direct sum of n copies of sl(N). The derivation is based on the Poisson reduction from the canonical brackets on the affine space over the cotangent bundle to the groups of automorphisms of vector bundles.

nlin.SI↗

Painleve VI, Rigid Tops and Reflection Equation

We show that the Painlev{é} VI equation has an equivalent form of the non-autonomous Zhukovsky-Volterra gyrostat. This system is a generalization of the Euler top in $C^3$ and include the additional constant gyrostat momentum. The quantization of its autonomous version is achieved by the reflection equation. The corresponding quadratic algebra generalizes the Sklyanin algebra. As by product we define integrable XYZ spin chain on a finite lattice with new boundary conditions.

math.QA↗

Elliptic Schlesinger system and Painlev{é} VI

We construct an elliptic generalization of the Schlesinger system (ESS) with positions of marked points on an elliptic curve and its modular parameter as independent variables (the parameters in the moduli space of the complex structure). ESS is a non-autonomous Hamiltonian system with pair-wise commuting Hamiltonians. The system is bihamiltonian with respect to the linear and the quadratic Poisson brackets. The latter are the multi-color generalization of the Sklyanin-Feigin-Odeskii classical algebras. We give the Lax form of the ESS. The Lax matrix defines a connection of a flat bundle of degree one over the elliptic curve with first order poles at the marked points. The ESS is the monodromy independence condition on the complex structure for the linear systems related to the flat bundle. The case of four points for a special initial data is reduced to the Painlev{é} VI equation in the form of the Zhukovsky-Volterra gyrostat, proposed in our previous paper.

nlin.SI↗

dS-AdS structures in the non-commutative Minkowski spaces

We consider a family of non-commutative 4d Minkowski spaces with the signature (1,3) and two types of spaces with the signature (2,2). The Minkowski spaces are defined by the common reflection equation and differ in anti-involutions. There exist two Casimir elements and the fixing of one of them leads to non-commutative "homogeneous" spaces $H_3$, $dS_3$, $AdS_3$ and light-cones. We present the quasi-classical description of the Minkowski spaces. There are three compatible Poisson structures - quadratic, linear and canonical. The quantization of the former leads to the considered Minkowski spaces. We introduce the horospheric generators of the Minkowski spaces. They lead to the horospheric description of $H_3$, $dS_3$ and $AdS_3$. The irreducible representations of Minkowski spaces $H_3$ and $dS_3$ are constructed. We find the eigen-functions of the Klein-Gordon equation in the terms of the horospheric generators of the Minkowski spaces. They give rise to eigen-functions on the $H_3$, $dS_3$, $AdS_3$ and light-cones.

hep-th↗

Universality of Calogero-Moser model

In this review we explain interrelations between the Elliptic Calogero-Moser model, integrable Elliptic Euler-Arnold top, monodromy preserving equations and the Knizhnik-Zamolodchikov-Bernard equation on a torus.

nlin.SI↗

Bihamiltonian structures and quadratic algebras in hydrodynamics and on non-commutative torus

We demonstrate the common bihamiltonian nature of several integrable systems. The first one is an elliptic rotator that is an integrable Euler-Arnold top on the complex group GL(N) for any $N$, whose inertia ellipsiod is related to a choice of an elliptic curve. Its bihamiltonian structure is provided by the compatible linear and quadratic Poisson brackets, both of which are governed by the Belavin-Drinfeld classical elliptic $r$-matrix. We also generalize this bihamiltonian construction of integrable Euler-Arnold tops to several infinite-dimensional groups, appearing as certain large $N$ limits of GL(N). These are the group of a non-commutative torus (NCT) and the group of symplectomorphisms $SDiff(T^2)$ of the two-dimensional torus. The elliptic rotator on symplectomorphisms gives an elliptic version of an ideal 2D hydrodynamics, which turns out to be an integrable system. In particular, we define the quadratic Poisson algebra on the space of Hamiltonians on $T^2$ depending on two irrational numbers. In conclusion, we quantize the infinite-dimensional quadratic Poisson algebra in a fashion similar to the corresponding finite-dimensional case.

nlin.SI↗

Large $N$ limit of integrable models

We consider a large $N$ limit of the Hitchin type integrable systems. The first system is the elliptic rotator on $GL_N$ that corresponds to the Higgs bundle of degree one over an elliptic curve with a marked point. This system is gauge equivalent to the $N$-body elliptic Calogero-Moser system, that is derived from the Higgs bundle of degree zero over the same curve. The large $N$ limit of the former system is the integrable rotator on the group of the non-commutative torus. Its classical limit leads to the integrable modification of 2d hydrodynamics on the two-dimensional torus. We also consider the elliptic Calogero-Moser system on the group of the non-commutative torus and consider the systems that arise after the reduction to the loop group.

nlin.SI↗

Hamiltonian Algebroids and deformations of complex structures on Riemann curves

Starting with a Lie algebroid ${\cal A}$ over a space $M$ we lift its action to the canonical transformations on the affine bundle ${\cal R}$ over the cotangent bundle $T^*M$. Such lifts are classified by the first cohomology $H^1({\cal A})$. The resulting object is a Hamiltonian algebroid ${\cal A}^H$ over ${\cal R}$ with the anchor map from $\G({\cal A}^H)$ to Hamiltonians of canonical transformations. Hamiltonian algebroids generalize Lie algebras of canonical transformations. We prove that the BRST operator for ${\cal A}^H$ is cubic in the ghost fields as in the Lie algebra case. The Poisson sigma model is a natural example of this construction. Canonical transformations of its phase space define a Hamiltonian algebroid with the Lie brackets related to the Poisson structure on the target space. We apply this scheme to analyze the symmetries of generalized deformations of complex structures on Riemann curves $\Si_{g,n}$ of genus $g $with $n$ marked points .We endow the space of local $\GL$-opers with the Adler-Gelfand-Dikii (AGD) Poisson brackets. It allows us to define a Hamiltonian algebroid over the phase space of $W_N$-gravity on $\Si_{g,n}$. The sections of the algebroid are Volterra operators on $\Si_{g,n}$ with the Lie brackets coming from the AGD bivector. The symplectic reduction defines the finite-dimensional moduli space of $W_N$-gravity and in particular the moduli space of the complex structures $\bp$ on $\Si_{g,n}$ deformed by the Volterra operators.

hep-th↗

Integrable tops and non-commutative torus

We consider the hydrodynamics of the ideal fluid on a 2-torus and its Moyal deformations. The both type of equations have the form of the Euler-Arnold tops. The Laplace operator plays the role of the inertia-tensor. It is known that 2-d hydrodynamics is non-integrable. After replacing of the Laplace operator by a distinguish pseudo-differential operator the deformed system becomes integrable. It is an infinite rank Hitchin system over an elliptic curve with transition functions from the group of the non-commutative torus. In the classical limit we obtain an integrable analog of the hydrodynamics on a torus with the inertia-tensor operator $\bar\partial^2$ instead of the conventional Laplace operator $\partial\bar\partial$.

nlin.SI↗

Hamiltonian Algebroid Symmetries in W-gravity and Poisson sigma-model

Starting from a Lie algebroid ${\cal A}$ over a space V we lift its action to the canonical transformations on the principle affine bundle ${\cal R}$ over the cotangent bundle $T^*V$. Such lifts are classified by the first cohomology $H^1({\cal A})$. The resulting object is the Hamiltonian algebroid ${\cal A}^H$ over ${\cal R}$ with the anchor map from $\G({\cal A}^H)$ to Hamiltonians of canonical transformations. Hamiltonian algebroids generalize the Lie algebras of canonical transformations. We prove that the BRST operator for ${\cal A}^H$ is cubic in the ghost fields as in the Lie algebra case. To illustrate this construction we analyze two topological field theories. First, we define a Lie algebroid over the space $V_3$ of $\SL$-opers on a Riemann curve $\Si_{g,n}$ of genus g with n marked points. The sections of this algebroid are the second order differential operators on $\Si_{g,n}$. The algebroid is lifted to the Hamiltonian algebroid over the phase space of $W_3$-gravity. We describe the BRST operator leading to the moduli space of $W_3$-gravity. In accordance with the general construction the BRST operator is cubic in the ghost fields. We present the Chern-Simons explanation of our results. The second example is the Hamiltonian algebroid structure in the Poisson sigma-model invoked by Cattaneo and Felder to describe the Kontsevich deformation quantization formula. The hamiltonian description of the Poisson sigma-model leads to the Lie algebraic form of the BRST operator.

hep-th↗

W-geometry and Isomonodromic Deformations

We introduce new times in the monodromy preserving equations. While the usual times related to the moduli of complex structures of Riemann curves such as coordinates of marked points, we consider the moduli of generalized complex structures ($W$-structures) as the new times. We consider linear differential matrix equations depending on $W$-structures on an arbitrary Riemann curve. The monodromy preserving equations have a Hamiltonian form. They are derived via the symplectic reduction procedure from a free gauge theory as well as the associate linear problems. The quasi-classical limit of isomonodromy problem leads to integrable hierarchies of the Hitchin type. In this way the generalized complex structures parametrized the moduli of these hierarchies.

nlin.SI↗