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تسجيل مستخدم جديدThe rotor-routing torsor and the Bernardi torsor disagree for every non-planar ribbon graph
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Changxin Ding
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Let $G$ be a ribbon graph. Matthew Baker and Yao Wang proved that the rotor-routing torsor and the Bernardi torsor for $G$, which are two torsor structures on the set of spanning trees for the Picard group of $G$, coincide when $G$ is planar. We prove the conjecture raised by them that the two torsors disagree when $G$ is non-planar.
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