Secondary cohomology operations that detect homotopy classes
نویسندگان
چکیده
منابع مشابه
Robot Motion Planning, Weights of Cohomology Classes, and Cohomology Operations
The complexity of algorithms solving the motion planning problem is measured by a homotopy invariant TC(X) of the configuration space X of the system. Previously known lower bounds for TC(X) use the structure of the cohomology algebra of X. In this paper we show how cohomology operations can be used to sharpen these lower bounds for TC(X). As an application of this technique we calculate explic...
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I Lewin, J. C., Science, 112, 652 (1950). 2 In the experiments reported here, cultures were grown on minimal medium plus sodium acetate (0.2 gm per 100 ml). The minimal medium, described in Levine, R. P., and Ebersold, W. T., Zeit. Vererbungs., 89, 632 (1958), was altered by a fivefold increase in the concentration of Beijerinck's solution. 3 Arnon, D. I., Plant Physiol., 24, 1 (1949). 4The aut...
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ژورنال
عنوان ژورنال: Topology
سال: 1984
ISSN: 0040-9383
DOI: 10.1016/0040-9383(84)90038-7