Local zeta regularization and the Casimir effect
  
  
  
      
    Davide Fermi, Livio Pizzocchero
  
  
  
  
  
  
                
    
  April 21, 2011  
  
    In this paper, whose aims are mainly pedagogical, we illustrate how to use
the local zeta regularization to compute the stress-energy tensor of the
Casimir effect. Our attention is devoted to the case of a neutral, massless
scalar field in flat space-time, on a space domain with suitable (e.g.,
Dirichlet) boundary conditions. After a simple outline of the local zeta
method, we exemplify it in the typical case of a field between two parallel
plates, or outside them. The results are shown to agree with the ones obtained
by more popular methods, such as point splitting regularization. In comparison
with these alternative methods, local zeta regularization has the advantage to
give directly finite results via analitic continuation, with no need to remove
or subtract divergent quantities.
  
  
    
  
  Keywords: 
Zeta regularization, Casimir effect