RT Journal Article T1 On homogeneous manifolds whose isotropy actions are polar A1 Díaz Ramos, José Carlos A1 Domínguez Vázquez, Miguel A1 Kollross, Andreas AB We show that simply connected Riemannian homogeneous spaces of compact semisimple Lie groups with polar isotropy actions are symmetric, generalizing results of Fabio Podestà and the third named author. Without assuming compactness, we give a classification of Riemannian homogeneous spaces of semisimple Lie groups whose linear isotropy representations are polar. We show for various such spaces that they do not have polar isotropy actions. Moreover, we prove that Heisenberg groups and non-symmetric Damek-Ricci spaces have non-polar isotropy actions. PB Springer YR 2018 FD 2018 LK http://hdl.handle.net/10347/35013 UL http://hdl.handle.net/10347/35013 LA eng NO Díaz-Ramos, J.C., Domínguez-Vázquez, M. & Kollross, A. On homogeneous manifolds whose isotropy actions are polar. manuscripta math. 161, 15–34 (2020) NO This version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature’s AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: http://dx.doi.org/10.1007/s00229-018-1077-1 NO The first and second authors have been supported by projects MTM2016-75897-P (AEI/FEDER, UE) and ED431F 2017/03 (Xunta de Galicia, Spain). The second author has received funding from the ICMAT Severo Ochoa project SEV-2015-0554 (MINECO, Spain), and from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 745722. DS Minerva RD 22 abr 2026