Invariant manifolds and Lax pairs for integrable nonlinear chains
    
    
  
  
  
      
      
      
        
Teoretičeskaâ i matematičeskaâ fizika, Tome 191 (2017) no. 3, pp. 369-388
    
  
  
  
  
  
    
      
      
        
      
      
      
    Voir la notice de l'article provenant de la source Math-Net.Ru
            
              			We continue the previously started study of the development of a direct method for constructing the Lax pair for a given integrable equation. This approach does not require any addition assumptions about the properties of the equation. As one equation of the Lax pair, we take the linearization of the considered nonlinear equation, and the second equation of the pair is related to its generalized invariant manifold. The problem of seeking the second equation reduces to simple but rather cumbersome calculations and, as examples show, is effectively solvable. It is remarkable that the second equation of this pair allows easily finding a recursion operator describing the hierarchy of higher symmetries of the equation. At first glance, the Lax pairs thus obtained differ from usual ones in having a higher order or a higher matrix dimensionality. We show with examples that they reduce to the usual pairs by reducing their order. As an example, we consider an integrable double discrete system of exponential type and its higher symmetry for which we give the Lax pair and construct the conservation laws.
			
            
            
            
          
        
      
                  
                    
                    
                    
                    
                    
                      
Mots-clés : 
Lax pair
Keywords: integrable chain, higher symmetry, invariant manifold, recursion operator.
                    
                  
                
                
                Keywords: integrable chain, higher symmetry, invariant manifold, recursion operator.
@article{TMF_2017_191_3_a0,
     author = {I. T. Habibullin and A. R. Khakimova},
     title = {Invariant manifolds and {Lax} pairs for integrable nonlinear chains},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {369--388},
     publisher = {mathdoc},
     volume = {191},
     number = {3},
     year = {2017},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_2017_191_3_a0/}
}
                      
                      
                    TY - JOUR AU - I. T. Habibullin AU - A. R. Khakimova TI - Invariant manifolds and Lax pairs for integrable nonlinear chains JO - Teoretičeskaâ i matematičeskaâ fizika PY - 2017 SP - 369 EP - 388 VL - 191 IS - 3 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/TMF_2017_191_3_a0/ LA - ru ID - TMF_2017_191_3_a0 ER -
I. T. Habibullin; A. R. Khakimova. Invariant manifolds and Lax pairs for integrable nonlinear chains. Teoretičeskaâ i matematičeskaâ fizika, Tome 191 (2017) no. 3, pp. 369-388. http://geodesic.mathdoc.fr/item/TMF_2017_191_3_a0/
