Local Galois theory in dimension two

This paper proves a generalization of Shafarevich's Conjecture, for fields of Laurent series in two variables over an arbitrary field. This result says that the absolute Galois group GK of such a field K is quasi-free of rank equal to the cardinality of K, i.e. every non-trivial finite split embedding problem for GK has exactly cardK proper solutions. We also strengthen a result of Pop and Haran–Jarden on the existence of proper regular solutions to split embedding problems for curves over large fields; our strengthening concerns integral models of curves, which are two-dimensional.

[1]  K. Gruenberg Projective Profinite Groups , 1967 .

[2]  Kenkichi Iwasawa,et al.  On Solvable Extentions of Algebraic Number Fields , 1953 .

[3]  M. Jarden,et al.  Regular split embedding problems over complete valued fields , 1998 .

[4]  David Harbater,et al.  FUNDAMENTAL GROUPS AND EMBEDDING PROBLEMS IN CHARACTERISTIC p , 2007 .

[5]  M. V. Dyke With an appendix by , 1969 .

[6]  A. Grothendieck,et al.  Théorie des Topos et Cohomologie Etale des Schémas , 1972 .

[7]  N. M. Katz Local-to-global extensions of representations of fundamental groups , 1986 .

[8]  I. Satake,et al.  On solvable extensions of algebraic number fields: Ann. of Math., (2) 58 (1953), 548–572 , 1953 .

[9]  D. Harbater,et al.  Abhyankar’s Local Conjecture on Fundamental Groups , 2004 .

[10]  S. Lang Algebraic Number Theory , 1971 .

[11]  D. Harbater,et al.  Patching and Thickening Problems , 1999 .

[12]  B. Deschamps,et al.  The regular inverse Galois problem over large fields , 1997 .

[13]  D. Harbater Patching and Galois Theory , 2003 .

[14]  A. Grothendieck,et al.  Éléments de géométrie algébrique , 1960 .

[15]  M. Jarden ON FREE PROFINITE GROUPS OF UNCOUNTABLE RANK , 2007 .

[16]  Florian Pop,et al.  Embedding problems over large fields , 1996 .

[17]  Tamara R. Lefcourt Galois groups and complete domains , 1999 .

[18]  B. Green,et al.  On valued function fields II. Regular functions and elements with the uniqueness property. , 1990 .

[19]  D. Harbater Galois coverings of the arithmetic line , 1987 .

[20]  S. Abhyankar,et al.  Recent Developments in the Inverse Galois Problem , 1995 .

[21]  Florian Pop,et al.  Étale Galois covers of affine smooth curves , 1995 .

[22]  Robin Hartshorne,et al.  Algebraic geometry , 1977, Graduate texts in mathematics.