Some problems in the theory of approximation of functions on compact homogeneous manifolds
    
    
  
  
  
      
      
      
        
Sbornik. Mathematics, Tome 200 (2009) no. 6, pp. 845-885
    
  
  
  
  
  
    
      
      
        
      
      
      
    Voir la notice de l'article provenant de la source Math-Net.Ru
            
              			Problems in the theory of approximation of functions on an arbitrary compact rank-one symmetric space $M$
in the metric of $L_p$, $1\le p\le\infty$, are investigated. The approximating functions are generalized spherical polynomials, that is, linear combinations of eigenfunctions of the Beltrami-Laplace operator on $M$.
Analogues of the direct Jackson theorems are proved for the modulus of smoothness (of arbitrary order) constructed by using the operator of spherical averaging. It is established that the modulus of smoothness and the $K$-functional constructed from the  Sobolev-type space corresponding to the Beltrami-Laplace differential operator are equivalent.
Bibliography: 35 titles.
			
            
            
            
          
        
      
                  
                    
                    
                    
                        
Keywords: 
approximation of functions, compact symmetric space, Jacobi polynomials, moduli of smoothness, Jackson's theorems.
                    
                    
                    
                  
                
                
                @article{SM_2009_200_6_a2,
     author = {S. S. Platonov},
     title = {Some problems in the theory of approximation of functions on compact homogeneous manifolds},
     journal = {Sbornik. Mathematics},
     pages = {845--885},
     publisher = {mathdoc},
     volume = {200},
     number = {6},
     year = {2009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2009_200_6_a2/}
}
                      
                      
                    S. S. Platonov. Some problems in the theory of approximation of functions on compact homogeneous manifolds. Sbornik. Mathematics, Tome 200 (2009) no. 6, pp. 845-885. http://geodesic.mathdoc.fr/item/SM_2009_200_6_a2/
