Postnikov sections of formal and hyperformal spaces
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- by Samuel B. Smith PDF
- Proc. Amer. Math. Soc. 122 (1994), 893-903 Request permission
Abstract:
Let X be a simply connected CW complex and ${X_n}$ its nth Postnikov section. We prove that X is formal provided ${H^q}({X_n},\mathbb {Q})$ is additively generated by decomposables for all q and n with $q > n$. Recall from [4] that a space X is said to be hyperformal if its rational cohomology algebra is the quotient of a free graded algebra by an ideal generated by a regular sequence. Using the main result of Felix and Halperin’s paper (Trans. Amer. Math. Soc. 270 (1982), 575-588) we show our sufficient condition for formality is actually equivalent to hyperformality.References
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Additional Information
- © Copyright 1994 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 122 (1994), 893-903
- MSC: Primary 55P62; Secondary 55S45
- DOI: https://doi.org/10.1090/S0002-9939-1994-1204385-5
- MathSciNet review: 1204385