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arXiv · 1804.02366

Integrable coupled Li$\acute{e}$nard-type systems with balanced loss and gain

Debdeep Sinha·Pijush K. Ghosh
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Abstract

A Hamiltonian formulation of generic many-particle systems with space-dependent balanced loss and gain coefficients is presented. It is shown that the balancing of loss and gain necessarily occurs in a pair-wise fashion. Further, using a suitable choice of co-ordinates, the Hamiltonian can always be reformulated as a many-particle system in the background of a pseudo-Euclidean metric and subjected to an analogous inhomogeneous magnetic field with a functional form that is identical with space-dependent loss/gain co-efficient.The resulting equations of motion from the Hamiltonian are a system of coupled Li$\acute{e}$nard-type differential equations. Partially integrable systems are obtained for two distinct cases, namely, systems with (i) translational symmetry or (ii) rotational invariance in a pseudo-Euclidean space. A total number of $m+1$ integrals of motion are constructed for a system of $2m$ particles, which are in involution, implying that two-particle systems are completely integrable. A few exact solutions for both the cases are presented for specific choices of the potential and space-dependent gain/loss co-efficients, which include periodic stable solutions. Quantization of the system is discussed with the construction of the integrals of motion for specific choices of the potential and gain-loss coefficients. A few quasi-exactly solvable models admitting bound states in appropriate Stoke wedges are presented.

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Debdeep Sinha, Pijush K. Ghosh. 2018-04-06. Integrable coupled Li$\acute{e}$nard-type systems with balanced loss and gain. https://doi.org/10.1016/j.aop.2018.11.013

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