A metric graph satisfying w(4)(1)=1 that cannot be lifted to a curve satisfying dim(W-4(1))=1

作者：Coppens Marc^*

来源：Open Mathematics, 2016, 14(1): 1-12.

DOI：10.1515/math-2016-0001

• Metric graphs
• Curves
• Lifting problems
• Special divisors
• Clifford index
• Dimension theorems

For all integers g >= 6 we prove the existence of a metric graph G with w(4)(1) = 1 such that G has Clifford index 2 and there is no tropical modification G' of G such that there exists a finite harmonic morphism of degree 2 from G' to a metric graph of genus 1. Those examples show that not all dimension theorems on the space classifying special linear systems for curves have immediate translation to the theory of divisors on metric graphs.

• 出版日期2016-2-9