article epub_ahead yes Viacheslav Goncharov author 8a0e2993-7114-11f0-b60e-f50e633649d8 GradSch department For Hamiltonian actions of semidirect products G = FxH, we study 2-cocycles arising from residual Hamiltonian actions of F on Hamiltonian reductions for H. The motivation comes from the study of Teichmüller spaces for surfaces with boundary, which carry Hamiltonian actions of the Virasoro algebra. In this paper, we give a general setup for the problem, and we suggest an easier way to obtain the Gelfand-Fuchs 2-cocycles for Hamiltonian actions on Teichmüller spaces. Elsevier2026 eng 0393-0440 1879-1662 2509.1616910.1016/j.geomphys.2026.105878 227 Goncharov, V. (2026). An easier way to compute 2-cocycles coming from a reduction for semidirect products. <i>Journal of Geometry and Physics</i>. Elsevier. <a href="https://doi.org/10.1016/j.geomphys.2026.105878">https://doi.org/10.1016/j.geomphys.2026.105878</a> V. Goncharov, Journal of Geometry and Physics 227 (2026). V. Goncharov, “An easier way to compute 2-cocycles coming from a reduction for semidirect products,” <i>Journal of Geometry and Physics</i>, vol. 227. Elsevier, 2026. Goncharov, Viacheslav. “An Easier Way to Compute 2-Cocycles Coming from a Reduction for Semidirect Products.” <i>Journal of Geometry and Physics</i>. Elsevier, 2026. <a href="https://doi.org/10.1016/j.geomphys.2026.105878">https://doi.org/10.1016/j.geomphys.2026.105878</a>. Goncharov, Viacheslav. “An Easier Way to Compute 2-Cocycles Coming from a Reduction for Semidirect Products.” <i>Journal of Geometry and Physics</i>, vol. 227, 105878, Elsevier, 2026, doi:<a href="https://doi.org/10.1016/j.geomphys.2026.105878">10.1016/j.geomphys.2026.105878</a>. Goncharov V. An easier way to compute 2-cocycles coming from a reduction for semidirect products. <i>Journal of Geometry and Physics</i>. 2026;227. doi:<a href="https://doi.org/10.1016/j.geomphys.2026.105878">10.1016/j.geomphys.2026.105878</a> Goncharov V. 2026. An easier way to compute 2-cocycles coming from a reduction for semidirect products. Journal of Geometry and Physics. 227, 105878. 219812026-06-10T07:29:13Z2026-06-16T09:23:39Z