Abstract
The variational problem of minimizing the energy functional that results in a second- order nonlinear differential equation of pendulum type on a finite interval with natural boundary conditions is analyzed. It is shown that the number of solutions of the boundary-value problem depends on the length \(L\) of the interval and unboundedly increases as \(L\to\infty\). The solutions on which the energy minimum is realized converge as \(L\to\infty\) to the solution of a variational problem in the class of periodic functions.
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Notes
Such conditions are usually said to be natural in contrast to the external conditions (sometimes called the principal conditions) which are imposed outside the variational problem, for example, by specifying the boundary values of the sought function.
They are small compared to the sample dimensions.
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Translated from Matematicheskie Zametki, 2021, Vol. 110, pp. 688–703 https://doi.org/10.4213/mzm12723.
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Kalyakin, L.A. Asymptotics of the Solution of a Variational Problem on a Large Interval. Math Notes 110, 687–699 (2021). https://doi.org/10.1134/S0001434621110055
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DOI: https://doi.org/10.1134/S0001434621110055