ALEXANDER INVARIANTS OF ARRANGEMENTS 3 Our results
نویسندگان
چکیده
Let A be an arrangement of n complex hyperplanes. The fundamental group of the complement of A is determined by a braid monodromy homomorphism, : Fs ! Pn. Using the Gassner representation of the pure braid group, we nd an explicit presentation for the Alexander invariant of A. From this presentation, we obtain combinatorial lower bounds for the ranks of the Chen groups of A. We also provide a combinatorial criterion for when these lower bounds are attained.
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