Sh:1142

• Corson, S. M., & Shelah, S. (2019). Deeply concatenable subgroups might never be free. J. Math. Soc. Japan, 71(4), 1123–1136. arXiv: 1804.05538 DOI: 10.2969/jmsj/80498049 MR: 4023299
• Abstract:
  We show that certain algebraic structures lack freeness in the absence of the axiom of choice. These include some subgroups of the Baer-Spevcker group \mathbb{Z}^\omega and the Hawaiian earring group. Applications to slenderness, completely metrizable topological groups, length functions and strongly bounded groups are also presented.
• published version (14p)

@article{Sh:1142,
 author = {Corson, Samuel M. and Shelah, Saharon},
 title = {{Deeply concatenable subgroups might never be free}},
 journal = {J. Math. Soc. Japan},
 fjournal = {Journal of the Mathematical Society of Japan},
 volume = {71},
 number = {4},
 year = {2019},
 pages = {1123--1136},
 issn = {0025-5645},
 mrnumber = {4023299},
 mrclass = {20K20 (03E25 03E35 03E75)},
 doi = {10.2969/jmsj/80498049},
 note = {\href{https://arxiv.org/abs/1804.05538}{arXiv: 1804.05538}},
 arxiv_number = {1804.05538}
}