The Riemann Integral in Weak Systems of Analysis
            
            
               Fernando Ferreira (Universidade de Lisboa, Portugal)  
              
             
            
            
               Gilda Ferreira (CMAF-Universidade de Lisboa, Portugal)  
              
             
                    
            
              Abstract: Taking as a starting point (a modification of) a   weak theory of arithmetic of Jan Johannsen and Chris Pollett   (connected with the hierarchy of counting   functions), we introduce successively stronger theories of   bounded arithmetic in order to set up a system   for analysis (TCA2). The   extended theories preserve the connection with the counting   hierarchy in the sense that the algorithms which the   systems prove to halt are exactly the ones in the hierarchy. We show   that TCA2 has the exact   strength to develop Riemannian integration for functions with a   modulus of uniform continuity. 
             
            
              Keywords: Riemann integral, counting hierarchy, weak analysis 
             
            Categories: F.1.3, F.4.1  
           |