Abstract
The full symmetric Toda system is a generalization of the open Toda chain, for which the Lax operator is a symmetric matrix of general form. This system is Liouville integrable and even superintegrable. Deift, Lee, Nando, and Tomei (DLNT) proposed the chopping method for constructing integrals of such a system. In the paper, a solution of Hamiltonian equations for the entire family of DLNT integrals is constructed by using the generalized QR factorization method. For this purpose, certain tensor operations on the space of Lax operators and special differential operators on the Lie algebra are introduced. Both tools can be interpreted in terms of the representation theory of the Lie algebra \(\mathfrak{sl}_n\) and are expected to generalize to arbitrary real semisimple Lie algebras. As is known, the full Toda system can be interpreted in terms of a compact Lie group and a flag space. Hopefully, the results on the trajectories of this system obtained in the paper will be useful in studying the geometry of flag spaces.
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Funding
The work on Sections 1, 2.1, 2.3, 3.1, 2.2, and Appendix was performed by Yu. B. Chernyakov, the work on Sections 2.4, 3.3, 4.1, and 4.2 was performed by D. V. Talalaev, and the work on Sections 3.2, 4.1, and 5 was performed by G. I. Sharygin. The work of G. I. Sharygin was supported by the Russian Science Foundation under grant no. 22-11-00272, https://rscf.ru/project/22-11-00272/, and carried out at Lomonosov Moscow State University, National Research Centre “Kurchatov Institute,” and Moscow Institute of Physics and Technology (National Research University). The work of D. V. Talalaev was carried out within the framework of a development program for Regional Scientific and Educational Mathematical Center of P. G. Demidov Yaroslavl State University under the support of the Ministry of Science and Higher Education of the Russian Federation (agreement no. 075-02-2022-886 on the provision of subsidy from the federal budget) and was partially supported by the Russian Foundation for Basic Research under grant no. 20-01-00157.
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Translated from Funktsional'nyi Analiz i ego Prilozheniya, 2023, Vol. 57, pp. 100–122 https://doi.org/10.4213/faa4105.
To I. M. Gel’fand, whose influence on mathematics cannot be overestimated
Translated by O. V. Sipacheva
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Talalaev, D.V., Chernyakov, Y.B. & Sharygin, G.I. Full Symmetric Toda System: Solution via QR-Decomposition. Funct Anal Its Appl 57, 346–363 (2023). https://doi.org/10.1134/S0016266323040081
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DOI: https://doi.org/10.1134/S0016266323040081