Rational summand in Hawaiian earring homology
ID: rational-summand-in-hawaiian-earring-homology
The first integral singular homology of the Hawaiian earring has a direct summand isomorphic to . This consequence of its structural homology theorem suffices, through the universal coefficient theorem for cohomology and nonzero Ext of the rationals with integer coefficients, to show that its integral is nonzero. The precise structural theorem is Theorem 3.1 of www.sas.rochester.edu/mth/sites/doug-ravenel/otherpapers/eda-kawamura2.pdf.
New to topics? Read the docs here!