Reconstructing under Group Actions
نویسندگان
چکیده
منابع مشابه
Reconstructing under Group Actions
We give a bound on the reconstructibility of an action G X in terms of the reconstructibility of a the action N X, where N is a normal subgroup of G, and the reconstructibility of the quotient G/N . We also show that if the action G X is locally finite, in the sense that every point is either in an orbit by itself or has finite stabilizer, then the reconstructibility of G X is at most t...
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We give a general structure theory for reconstructing group actions on sets without any assumptions on the group, the action, or the set on which the group acts. Using certain ‘local data’ D from the action we build a group G(D) of the data and a space X (D) with an action of G(D) on X (D) that arise naturally from the data D. We use these to obtain an approximation to the original group G, the...
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Let G be a simple primitive subgroup of Sn, speciied in terms of a set of generating permutations. If jGj n 5 , eecient algorithms are presented that nd \the most natural permutation representation" of G. For example, if G is a classical group then we nd a suitable projective space underlying G. A number of related questions are considered. Our notion of \eeciency" takes into account many exist...
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ژورنال
عنوان ژورنال: Graphs and Combinatorics
سال: 2006
ISSN: 0911-0119,1435-5914
DOI: 10.1007/s00373-006-0675-y