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Reduced Wu and generalized Simon invariants for spatial graphs

Published online by Cambridge University Press:  20 February 2014

ERICA FLAPAN
Affiliation:
Department of Mathematics, Pomona College, Claremont, CA 91711, U.S.A. e-mail: [email protected]
WILL FLETCHER
Affiliation:
Biophysics Program, Stanford University, Stanford, CA 94305, U.S.A. e-mail: [email protected]
RYO NIKKUNI
Affiliation:
Department of Mathematics, Tokyo Woman's Christian University, 2-6-1 Zempukuji, Suginami-ku, Tokyo 167-8585, Japan. e-mail: [email protected]

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
Copyright
Copyright © Cambridge Philosophical Society 2014 

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References

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