Characterizing co-NL by a group action

Clément Aubert (1) , Thomas Seiller (2)

1 LIPN - Laboratoire d'Informatique de Paris-Nord
2 IHES - Institut des Hautes Études Scientifiques

In a recent paper, Girard proposes to use his recent construction of a geometry of interaction in the hyperfinite factor in an innovative way to characterize complexity classes. We begin by giving a detailed explanation of both the choices and the motivations of Girard's definitions. We then provide a complete proof that the complexity class co-NL can be characterized using this new approach. We introduce as a technical tool the non-deterministic pointer machine, a concrete model to computes algorithms.

Domaines: Logique en informatique [cs.LO]; Complexité [cs.CC]; Logique [math.LO]; Algèbres d'opérateurs [math.OA]

Clément Aubert, Thomas Seiller. Characterizing co-NL by a group action. Mathematical Structures in Computer Science, 2014, First View, pp.1--33. ⟨10.1017/S0960129514000267⟩. ⟨hal-01005705⟩