{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T14:24:09Z","timestamp":1780064649493,"version":"3.54.0"},"reference-count":35,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2016,7,8]],"date-time":"2016-07-08T00:00:00Z","timestamp":1467936000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>We derive a Hamiltonian version of the    PT   -symmetric discrete nonlinear Schr\u00f6dinger equation that describes synchronized dynamics of coupled pendula driven by a periodic movement of their common strings. In the limit of weak coupling between the pendula, we classify the existence and spectral stability of breathers (time-periodic solutions localized in the lattice) supported near one pair of coupled pendula. Orbital stability or instability of breathers is proved in a subset of the existence region.<\/jats:p>","DOI":"10.3390\/sym8070059","type":"journal-article","created":{"date-parts":[[2016,7,8]],"date-time":"2016-07-08T09:46:07Z","timestamp":1467971167000},"page":"59","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Breathers in Hamiltonian                                        PT                                 -Symmetric Chains of Coupled Pendula under a Resonant Periodic Force"],"prefix":"10.3390","volume":"8","author":[{"given":"Alexander","family":"Chernyavsky","sequence":"first","affiliation":[{"name":"Department of Mathematics, McMaster University, Hamilton, ON L8S 4K1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dmitry","family":"Pelinovsky","sequence":"additional","affiliation":[{"name":"Department of Mathematics, McMaster University, Hamilton, ON L8S 4K1, Canada"},{"name":"Department of Applied Mathematics, Nizhny Novgorod State Technical University, Nizhny Novgorod, 603950, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,7,8]]},"reference":[{"key":"ref_1","unstructured":"Huygens, C. 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