=ADD= =reftype= 14 =number= 00-10 =url= ftp://ftp.risc.uni-linz.ac.at/pub/techreports/2000/00-10.ps.gz =year= 2000 =month= 04 =author= Stadelmeyer; Peter =title= Algebraic Extensions in the Resolution of Curve-Singularities =abstract= Let $\acurveC$ be an irreducible algebraic curve in the affine plane and let $\cbranch$ be a curve-branch of $\curveC$. In this paper we compare the algebraic extensions necessary to resolve $\cbranch$ either by quadratic transformations or Puiseux-series expansions. It is well known that the residual field of $\cbranch$ is isomorphic to the coefficient field of a rational Puiseux-expansion of $\cbranch$. We will show, that this is also true for the coefficient field of quadratic transformations of $\cbranch$. This allows us to give an a-priory bound for the degree of the field extension necessary to resolve $\cbranch$. We will also present an alternative definition of rational Puiseux-expansions based on the implicit function theorem and quadratic transformations. =sponsor= FWF project number P11160-TEC ``HySaX'' =keywords= algebraic geometry, plane curves, algebraic extensions, resolution, Puiseux series, quadratic transformations, singularities