Searcharxiv⌕ Search

arXiv subjects

Partha Guha

Publications and source records attributed to Partha Guha.

At least 73 records · Page 4Linked to original sources

First integrals of Generalized Darboux-Halphen systems and Membrane Paradigm

The Darboux-Halphen system of equations have common or individual additive terms depending on the matrices defining Yang-Mills gauge potential fields. Tod (Phys. Lett. A 190 (1994) 221-224), described a conserved quantity for the classical systems with no additive terms. We show that the conserved quantity apply even for the generalized cases with common additive terms. A theory has been presented, with an example, of how to formulate conserved quantities for equation with individual additive terms. We also briefly shed some light on the issues of surface motions of fluids in conncetion to Nahm`s equation and the self-duality and integrability of membrane dynamics.

hep-th↗

Generalized damped Milne-Pinney equation and Chiellini method

We adopt the Chiellini integrability method to find the solutions of various generalizations of the damped Milne-Pinney equations. In particular, we find the solution of the damped Ermakov-Painlevé II equation and generalized dissipative Milne-Pinney equation.

nlin.SI↗

Bianchi-IX, Darboux-Halphen and Chazy-Ramanujan

Bianchi-IX four metrics are $SU(2)$ invariant solutions of vacuum Einstein equation, for which the connection-wise self-dual case describes the Euler Top, while the curvature-wise self-dual case yields the Ricci flat classical Darboux-Halphen system. It is possible to see such a solution exhibiting Ricci flow. The classical Darboux-Halphen system is a special case of the generalized one that arises from a reduction of the self-dual Yang-Mills equation and the solutions to the related homogeneous quadratic differential equations provide the desired metric. A few integrable and near-integrable dynamical systems related to the Darboux-Halphen system and occurring in the study of Bianchi IX gravitational instanton have been listed as well. We explore in details whether self-duality implies integrability.

hep-th↗

Bi-Hamiltonian Structures of Chaotic Dynamical Systems in 3D

We study Poisson structures of dynamical systems with three degrees of freedom which are known for their chaotic properties, namely Lü, modified Lü, Chen, $T$ and Qi systems. We show that all these flows admit bi-Hamiltonian structures depending on the values of their parameters.

math-ph↗

Superintegrable Cases of Four Dimensional Dynamical Systems

Degenerate tri-Hamiltonian structures of Shivamoggi and generalized Raychaudhuri equations are exhibited. For certain specific values of the parameters, it is shown that hyperchaotic Lü and Qi systems are superintegrable and admit tri-Hamiltonian structures.

math.DS↗

Generalized Virasoro algebra: left-symmetry and related algebraic and hydrodynamic properties

Motivated by the work of Kupershmidt (J. Nonlin. Math. Phys. 6 (1998), 222 --245) we discuss the occurrence of left symmetry in a generalized Virasoro algebra. The multiplication rule is defined, which is necessary and sufficient for this algebra to be quasi-associative. Its link to geometry and nonlinear systems of hydrodynamic type is also recalled. Further, the criteria of skew-symmetry, derivation and Jacobi identity making this algebra into a Lie algebra are derived. The coboundary operators are defined and discussed. We deduce the hereditary operator and its generalization to the corresponding $3-$ary bracket. Further, we derive the so-called $ρ-$compatibility equation and perform a phase-space extension. Finally, concrete relevant particular cases are investigated.

math-ph↗

Geometrical and Dynamical Aspects of Nonlinear Higher-Order Riccati Systems

We study a geometrical formulation of the nonlinear second-order Riccati equation (SORE) in terms of the projective vector field equation on $S^1$, whichn in turn is related to the stability algebra of Virasoro orbit. Using Darboux integrability method we obtain the first-integral of SORE and the results are applied to the study of its Lagrangian and Hamiltonian description. We unveil the relation between the Darboux polynomials and master symmetries associated to second-order Riccati. Using these results we show the existence of a Lagrangian description for the related system, and the Painlevé II equation is analysed.

math-ph↗

Fradkin-Bacry-Ruegg-Souriau vector in kappa-deformed space-time

We study presence of an additional symmetry of a generic central potential in the $κ$-space-time. An explicit construction of Fradkin and Bacry, Ruegg, Souriau (FBRS) for a central potential is carried out and the piece-wise conserved nature of the vector is established. We also extend the study to Kepler systems with a drag term, particularly Gorringe-Leach equation is generalized to the $κ$-deformed space. The possibility of mapping Gorringe-Leach equation to an equation with out drag term is exploited in associating a similar conserved vector to system with a drag term. An extension of duality between two class of central potential is introduced in the $κ$-deformed space and is used to investigate the duality existing between two class of Gorringe-Leach equations. All the results obtained can be retraced to the correct commutative limit as we let $a \rightarrow 0$.

hep-th↗

Noncommutative Classical Dynamics on Velocity Phase Space and Souriau Formalism

We consider Feynman-Dyson's proof of Maxwell's equations using the Jacobi identities on the velocity phase space. In this paper we generalize the Feynman-Dyson's scheme by incorporating the non-commutativity between various spatial coordinates along with the velocity coordinates. This allows us to study a generalized class of Hamiltonian systems. We explore various dynamical flows associated to the Souriau form associated to this generalized Feynman-Dyson's scheme. Moreover, using the Souriau form we show that these new classes of generalized systems are volume preserving mechanical systems.

math-ph↗

MICZ Kepler Systems in Noncommutative Space and Duality of Force Laws

In this paper, we analyze the modification of integrable models in the $κ$-deformed space-time. We show that two dimensional isotropic oscillator problem, Kepler problem and MICZ-Kepler problem in $κ$-deformed space-time admit integrals of motion as in the commutative space. We also show that the duality equivalence between $κ$-deformed Kepler problem and $κ$-deformed two-dimensional isotropic oscillator explicitly, by deriving Bohlin-Sundman transformation which maps these two systems. These results are valid to all orders the the deformation parameter.

hep-th↗

Study of the family of Nonlinear Schrodinger equations by using the Adler-Kosant-Symes framework and the Tu methodology and their Non-holonomic deformation

The objective of this work is to explore the class of equations of the Non-linear Schrodinger type by employing the Adler-Kostant-Symes theorem and the Tu methodology.In the first part of the work, the AKS theory is discussed in detail showing how to obtain the non-linear equations starting from a suitably chosen spectral problem.Equations derived by this method include different members of the NLS family like the NLS, the coupled KdV type NLS, the generalized NLS, the vector NLS, the Derivative NLS, the Chen-Lee-Liu and the Kundu-Eckhaus equations. In the second part of the paper, the steps in the Tu methodology that are used to formulate the hierarchy of non-linear evolution equations starting from a spectral problem, are outlined. The AKNS, Kaup-Newell, and generalized DNLS hierarchies are obtained by using this algorithm. Several reductions of the hierarchies are illustrated. The famous trace identity is then applied to obtain the Hamiltonian structure of these hierarchies and establish their complete integrability. In the last part of the paper, the non-holonomic deformation of the class of integrable systems belonging to the NLS family is studied. Equations examined include the NLS, coupled KdV-type NLS and Derivative NLS (both Kaup-Newell and Chen-Lee-Liu equations). NHD is also applied to the hierarchy of equations in the AKNS system and the KN system obtained through application of the Tu methodology.Finally, we discuss the connection between the two formalisms and indicate the directions of our future endeavour in this area.

nlin.SI↗

A study of two new generalized negative KdV type equations

We give a simple geometric interpretation of the mapping of the negative KdV equation as proposed by Qiao and Li {arXiv:1101.1605 [math-ph], Europhys. Lett.,94 (2011) 50003} and the Fuchssteiner equation using geometry of projective connection on S1 or stabilizer set of the Virasoro orbit. We propose a similar connection between with the higher-order negative KdV equations of Fuchssteiner type described as and respectively. We study the Painleve and symmetry analyses of these newly found equations and show that they yield soliton solutions.

math-ph↗

A Quasi-Lie Schemes Approach to Second-Order Gambier Equations

A quasi-Lie scheme is a geometric structure that provides t-dependent changes of variables transforming members of an associated family of systems of first-order differential equations into members of the same family. In this note we introduce two quasi-Lie schemes for studying second-order Gambier equations in a geometric way. This allows us to study the transformation of these equations into simpler canonical forms, which solves a gap in the previous literature, and other relevant differential equations, which leads to derive new constants of motion for families of second-order Gambier equations. Additionally, we describe general solutions of certain second-order Gambier equations in terms of particular solutions of Riccati equations, linear systems, and t-dependent frequency harmonic oscillators.

math-ph↗

A generalized non-Hermitian Pais-Uhlenbeck quantum Hamiltonian, its Hermitian equivalence and position-dependent mass correspondence

We explore the Jacobi Last Multiplier as a means for deriving the Lagrangian of a fourth-order differential equation. In particular we consider the classical problem of the Pais-Uhlenbeck oscillator and write down the accompanying Hamiltonian. We then compare such an expression with an alternative derivation of the Hamiltonian that makes use of the Ostrogradski's method and show that a mapping from the one to the other is achievable by variable transformations. Assuming canonical quantization procedure to be valid we go for the operator version of the Hamiltonian that represents a pair of uncoupled oscillators. This motivates us to propose a generalized Pais-Uhlenbeck Hamiltonian in terms of the usual harmonic oscillator creation and annihilation operators by including terms quadratic and linear in them. Such a Hamiltonian turns out to be essentially non-Hermitian but has an equivalent Hermitian representation which is reducible to a typically position-dependent reduced mass form.

math-ph↗

A Lagrangian Description of the Higher-Order Painlevé Equations

We derive the Lagrangians of the higher-order Painlevé equations using Jacobi's last multiplier technique. Some of these higher-order differential equations display certain remarkable properties like passing the Painlevé test and satisfy the conditions stated by Jurá$\check{s}$, (Acta Appl. Math. 66 (2001) 25--39), thus allowing for a Lagrangian description.

nlin.SI↗

Dynamical Studies of Equations from the Gambier Family

We consider the hierarchy of higher-order Riccati equations and establish their connection with the Gambier equation. Moreover we investigate the relation of equations of the Gambier family to other nonlinear differential systems. In particular we explore their connection to the generalized Ermakov-Pinney and Milne-Pinney equations. In addition we investigate the consequence of introducing Okamoto's folding transformation which maps the reduced Gambier equation to a Liénard type equation. Finally the conjugate Hamiltonian aspects of certain equations belonging to this family and their connection with superintegrability are explored.

nlin.SI↗

Higher-order Abel equations: Lagrangian formalism, first integrals and Darboux polynomials

A geometric approach is used to study a family of higher-order nonlinear Abel equations. The inverse problem of the Lagrangian dynamics is studied in the particular case of the second-order Abel equation and the existence of two alternative Lagrangian formulations is proved, both Lagrangians being of a non-natural class (neither potential nor kinetic term). These higher-order Abel equations are studied by means of their Darboux polynomials and Jacobi multipliers. In all the cases a family of constants of the motion is explicitly obtained. The general n-dimensional case is also studied.

math-ph↗