Free energy asymptotics of the quantum Heisenberg spin chain Napiórkowski, Marcin M Seiringer, Robert ; https://orcid.org/0000-0002-6781-0521 ddc:510 We consider the ferromagnetic quantum Heisenberg model in one dimension, for any spin S≥1/2. We give upper and lower bounds on the free energy, proving that at low temperature it is asymptotically equal to the one of an ideal Bose gas of magnons, as predicted by the spin-wave approximation. The trial state used in the upper bound yields an analogous estimate also in the case of two spatial dimensions, which is believed to be sharp at low temperature. Springer Nature 2021 info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/9256 https://research-explorer.ista.ac.at/download/9256/9273 Napiórkowski MM, Seiringer R. Free energy asymptotics of the quantum Heisenberg spin chain. <i>Letters in Mathematical Physics</i>. 2021;111(2). doi:<a href="https://doi.org/10.1007/s11005-021-01375-4">10.1007/s11005-021-01375-4</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1007/s11005-021-01375-4 info:eu-repo/semantics/altIdentifier/issn/0377-9017 info:eu-repo/semantics/altIdentifier/e-issn/1573-0530 info:eu-repo/semantics/altIdentifier/wos/000626837400001 info:eu-repo/semantics/altIdentifier/pmid/33785980 info:eu-repo/semantics/openAccess