Derivatives at the boundary for analytic Lipschitz functions
    
    
  
  
  
      
      
      
        
Sbornik. Mathematics, Tome 207 (2016) no. 10, pp. 1471-1490
    
  
  
  
  
  
    
      
      
        
      
      
      
    Voir la notice de l'article provenant de la source Math-Net.Ru
            
              			We consider the behaviour of holomorphic functions on a bounded open subset of the plane, satisfying a Lipschitz condition with exponent $\alpha$, with $0\alpha1$, in the vicinity of an exceptional boundary point where all such functions exhibit some kind of smoothness. Specifically, we consider the relation between the abstract idea of a bounded point derivation on the algebra of such functions and the classical complex derivative evaluated as a limit of difference quotients. We show that whenever such a bounded point derivation exists at a boundary point $b$, it may be evaluated by taking a limit of classical difference quotients, approaching from a set having full area density at $b$.
Bibliography: 13 titles.
			
            
            
            
          
        
      
                  
                    
                    
                    
                        
Keywords: 
analytic function, boundary, Lipschitz condition, point derivation, difference quotient, capacity
Mots-clés : Hausdorff content.
                    
                  
                
                
                Mots-clés : Hausdorff content.
@article{SM_2016_207_10_a7,
     author = {A. G. O'Farrell},
     title = {Derivatives at the boundary for analytic {Lipschitz} functions},
     journal = {Sbornik. Mathematics},
     pages = {1471--1490},
     publisher = {mathdoc},
     volume = {207},
     number = {10},
     year = {2016},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2016_207_10_a7/}
}
                      
                      
                    A. G. O'Farrell. Derivatives at the boundary for analytic Lipschitz functions. Sbornik. Mathematics, Tome 207 (2016) no. 10, pp. 1471-1490. http://geodesic.mathdoc.fr/item/SM_2016_207_10_a7/
