Intersection cohomology of $S\sp 1$-actions
نویسندگان
چکیده
منابع مشابه
Intersection Cohomology of S1-actions on Pseudomanifolds
For any smooth free action of the unit circle S in a manifold M ; the Gysin sequence of M is a long exact sequence relating the DeRham cohomologies of M and its orbit space M/S. If the action is not free then M/S is not a manifold but a stratified pseudomanifold and there is a Gysin sequence relating the DeRham cohomology of M with the intersection cohomology of M/S. In this work we extend the ...
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A classical result says that a free action of the circle S on a topological space X is geometrically classified by the orbit space B and by a cohomological class e ∈ H 2 (B,Z), the Euler class. When the action is not free we have a difficult open question: Π : “Is the space X determined by the orbit space B and the Euler class?” The main result of this work is a step towards the understanding o...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1993
ISSN: 0002-9947,1088-6850
DOI: 10.1090/s0002-9947-1993-1116314-7