@techreport{TR-IC-09-34,
   number = {IC-09-34},
   author = {Igor Carboni Oliveira and Arnaldo Vieira Moura and Walter
                   Carnielli},
   title  =  {On  an  Abstract  Theory of Computational Models and the
                   Converse of {R}ice's Theorem},
   month = {September},
   year = {2009},
   institution = {Institute of Computing, University of Campinas},
   note = {In English, 13 pages.
    \par\selectlanguage{english}\textbf{Abstract}
       In  this  paper  we  put  forward  an  abstract  definition  of 
       computational   model  and  provide  a  negative  answer  to  a 
       conjecture   involving  the  converse  of  Rice's  theorem.  In 
       particular, any reasonable formal system in which the notion of
       computation  is  involved should satisfy our general definition
       of computational model. Furthermore, in order to give a natural
       counter-example   to   our   conjecture   we   present   a  new 
       interpretation   to   a   result   of  Bernardi  [1]  involving 
       undecidability in sufficiently strong formal theories. Finally,
       we  raise  the  question if an abstract theory of computational
       models  can  lead  to  new  problems and interesting results in
       theoretical computer science.
  }
}