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Reduced Wu and generalized Simon invariants for spatial graphs

Published online by Cambridge University Press:  20 February 2014

ERICA FLAPAN ,
WILL FLETCHER  and
RYO NIKKUNI
ERICA FLAPAN
Affiliation:
Department of Mathematics, Pomona College, Claremont, CA 91711, U.S.A. e-mail: eflapan@pomona.edu
WILL FLETCHER
Affiliation:
Biophysics Program, Stanford University, Stanford, CA 94305, U.S.A. e-mail: willf@stanford.edu
RYO NIKKUNI
Affiliation:
Department of Mathematics, Tokyo Woman's Christian University, 2-6-1 Zempukuji, Suginami-ku, Tokyo 167-8585, Japan. e-mail: nick@lab.twcu.ac.jp
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Abstract

We introduce invariants of graphs embedded in S3 which are related to the Wu invariant and the Simon invariant. Then we use our invariants to prove that certain graphs are intrinsically chiral, and to obtain lower bounds for the minimal crossing number of particular embeddings of graphs in S3.

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 156 , Issue 3 , May 2014 , pp. 521 - 544
Copyright
Copyright © Cambridge Philosophical Society 2014 

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