170292 20260410165451.0 doi 10.1016/j.jfa.2026.111492 sideral 148821 ART-2026-148821 eng Oliva-Maza, J. Universidad de Zaragoza (orcid)0000-0001-8546-5883 On similarity to contraction semigroups and tensor products, I 2026 In the context of finite tensor products of Hilbert spaces, we prove that similarity of a tensor product of operator semigroups to a contraction semigroup is equivalent to the corresponding similarity for each factor, after an appropriate rescaling. A similar result holds with contractivity replaced by quasi-contractivity. This splitting phenomenon allows us to construct new and, in a sense, the strongest possible examples of C_0-semigroups not similar to contractions, thus completing an important chapter of the theory. We also address the discrete setting and relate it to our results. info:eu-repo/grantAgreement/ES/AEI/AEI PID2022-137294NB-I00 info:eu-repo/grantAgreement/ES/DGA/E48-23R info:eu-repo/semantics/closedAccess All rights reserved http://www.europeana.eu/rights/rr-f/ info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Tomilov, Y. 2006 015 Universidad de Zaragoza Dpto. Matemáticas Área Análisis Matemático (2026), 111492 [37 pp.] J. funct. anal. JOURNAL OF FUNCTIONAL ANALYSIS 0022-1236 968668 http://zaguan.unizar.es/record/170292/files/texto_completo.pdf Versión publicada info:eu-repo/date/embargoEnd/2028-03-31 1003105 http://zaguan.unizar.es/record/170292/files/texto_completo.jpg?subformat=icon icon Versión publicada info:eu-repo/date/embargoEnd/2028-03-31 oai:zaguan.unizar.es:170292 articulos driver 2026-04-10-13:45:59 ARTICLE