$\mathrm{Op}^*$ and $\mathrm{C}^*$ dynamical systems.
    
    
  
  
  
      
      
      
        
Teoretičeskaâ i matematičeskaâ fizika, Tome 82 (1990) no. 3, pp. 323-330
    
  
  
  
  
  
    
      
      
        
      
      
      
    Voir la notice de l'article provenant de la source Math-Net.Ru
            
              			According to the results of Part I [1], the only nontrivial difference between the vacuum struclures of $\mathrm{Op}^*$ and $\mathrm{C}^*$ dynamical systems is the effect of the infinite vacuum degeneracy in irreducible $\mathrm{Op}^*$ systems. For brevity, this effect is referred to as the “Borchers anomaly”, and is analyzed in detail by means of new mathematical tools – the recently introduced unbounded commutants of $\mathrm{Op}^*$ operators. A simple representation is obtained for the vacuum subspace of any field theory with cyclic vacuum in terms of the unbounded commutant of the field algebra, and from this representation a new necessary and sufficient condition for uniqueness of the vacuum is obtained. Some conditions for absence of the Borchers anomaly are derived, and a comparison which shows how these conditions improve the ones previously known is made.
			
            
            
            
          
        
      @article{TMF_1990_82_3_a0,
     author = {A. V. Voronin and S. S. Horuzhy},
     title = {$\mathrm{Op}^*$ and $\mathrm{C}^*$ dynamical systems.},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {323--330},
     publisher = {mathdoc},
     volume = {82},
     number = {3},
     year = {1990},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1990_82_3_a0/}
}
                      
                      
                    A. V. Voronin; S. S. Horuzhy. $\mathrm{Op}^*$ and $\mathrm{C}^*$ dynamical systems.. Teoretičeskaâ i matematičeskaâ fizika, Tome 82 (1990) no. 3, pp. 323-330. http://geodesic.mathdoc.fr/item/TMF_1990_82_3_a0/
                  
                