Existence of supercritical pasting arcs for two sheeted spheres
Nakai, Mitsuru
Kodai Math. J., Tome 29 (2006) no. 1, p. 163-169 / Harvested from Project Euclid
Take e.g. two disjoint nondegenerate compact continua A and B in the complex plane C with connected complements and pick a simple arc γ in the complex sphere Ĉ disjoint from A ∪ B, which we call a pasting arc for A and B. Construct a covering Riemann surface Ĉγ over Ĉ by pasting two copies of $\widehat{\Bbb C}\setminus\gamma$ crosswise along γ. We embed A in one sheet and B in another sheet of two sheets of Ĉγ which are copies of $\widehat{\Bbb C}\setminus\gamma$ so that $\widehat{\Bbb C}_{\gamma}\setminus A \cup B$ is understood as being obtained by pasting $($\widehat{\Bbb C}\setminus A)\setminus \gamma$ with $($\widehat{\Bbb C}\setminus B)\setminus \gamma$ crosswise along γ. In the comparison of the variational 2 capacity cup(A, $\widehat{\Bbb C}_{\gamma}\setminus B$ ) of the compact set A considered in the open set $\widehat{\Bbb C}_{\gamma}\setminus B$ with the corresponding cap(A, $\widehat{\Bbb C}\setminus B$ ), we say that the pasting arc γ for A and B is subcritical, critical, or supercritical according as cap(A, $\widehat{\Bbb C}_{\gamma}\setminus B$ ) is less than, equal to, or greater than cap(A, $\widehat{\Bbb C}\setminus B$ ), respectively. We have shown in our former paper [4] the existence of pasting arc γ of any one of the above three types but that of supercritical and critical type was only shown under the additional requirment on A and B that A and B are symmetric about a common straight line simultaneously. The purpose of the present paper is to show that in the above mentioned result the additional symmetry assumption is redundant: we will show the existence of supercritical and hence of critical arc γ starting from an arbitrarily given point in $\widehat{\Bbb C}\setminus A \cup B$ for any general admissible pair of A and B without any further requirment whatsoever.
Publié le : 2006-06-14
Classification: 
@article{1151936433,
     author = {Nakai, Mitsuru},
     title = {Existence of supercritical pasting arcs for two sheeted spheres},
     journal = {Kodai Math. J.},
     volume = {29},
     number = {1},
     year = {2006},
     pages = { 163-169},
     language = {en},
     url = {http://dml.mathdoc.fr/item/1151936433}
}
Nakai, Mitsuru. Existence of supercritical pasting arcs for two sheeted spheres. Kodai Math. J., Tome 29 (2006) no. 1, pp.  163-169. http://gdmltest.u-ga.fr/item/1151936433/