What is definition of isotopy of pants decomposition in the following paper ?
when two pants decompositions is isotopic? Also why we say cut system what is definition of system ?
In Hatcher, Allen; Lochak, Pierre; Schneps, Leila, On the Teichmüller tower of mapping class groups, J. Reine Angew. Math. 521, 1-24 (2000). ZBL0953.20030..