Subsymmetric sequences and minimal spaces

نویسنده

  • Anna Maria Pelczar
چکیده

W.T.Gowers proved in [G1] the celebrated dichotomy concerning unconditional sequences and hereditarily indecomposable spaces using Ramsey-type argumentation. In [G2] he generalized the reasoning and showed, as an application, a dichotomy concerning quasiminimal spaces, ie. in which any two infinitely dimensional subspaces contain further two infinitely dimensional subspaces which are isomorphic. Putting these results together he obtained the following ”classification” theorem [G2]:

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تاریخ انتشار 2008