Complements of Curves in Closed Surfaces: Homeomorphic?

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SUMMARY

The discussion centers on the homeomorphism of surfaces after the removal of non-isotopic curves in a compact, oriented surface S. It is established that removing a disk and a meridian from S does not yield homeomorphic surfaces, contradicting the initial claim. The corrected result is referenced from Farb and Margalit's "Primer on Mapping Class Groups," specifically regarding the change of coordinates principle, which states that an orientation-preserving homeomorphism exists if the corresponding cut surfaces are homeomorphic.

PREREQUISITES
  • Understanding of compact, oriented surfaces in topology
  • Familiarity with simple closed curves (s.c.c) and their properties
  • Knowledge of homeomorphism concepts in topology
  • Basic understanding of homology groups, particularly H^1 (T^2)
NEXT STEPS
  • Study Farb and Margalit's "Primer on Mapping Class Groups" for in-depth knowledge on the change of coordinates principle
  • Explore the properties of simple closed curves in compact surfaces
  • Research the implications of homology in topology, focusing on H^1 groups
  • Investigate the concept of isotopy and its role in determining homeomorphism
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Mathematicians, topologists, and students studying algebraic topology, particularly those interested in the properties of surfaces and mapping class groups.

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Hi, let ## \alpha, \gamma ## be non-isotopic curves in a compact, oriented surface S. There is a result to the effect that ## S-\alpha## is homeo. to ## S- \gamma ## . This is not true as stated; we can , e.g., remove a disk (trivial class) in a copy of S and then remove a meridian ( a generator of ## H^1 (T^2) ##). Does anyone know the corrected result? This is not true either if we only remove essential curves. It seems like if ##\alpha, \gamma## actually _were_ isotopic , then this would be true. Or maybe if they were homologous?
Thanks.
 
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I seem to remember coming across the result you are looking for in Farb and Margalit's Primer on Mapping Class Groups, in chapter 1, if I am not mistaken. I think maybe they call it the change of coordinates principle.
 
http://www.math.ethz.ch/~bgabi/Farb%20Magalit%20January%202011%20version.pdf
 
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Thanks; in case anyone else is interested, here it is, towards the bottom of p.39:

There is an orientation-preserving homeo. of a surface S taking one s.c.c * ## \gamma## to ## \beta## iff the
corresponding cut surfaces ##S -\gamma ## , ##S- \beta ## are homeomorphic.

*s.c.c: Simple-Closed Curve.
 

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