Sciweavers

LOGCOM
2007
72views more  LOGCOM 2007»
13 years 11 months ago
Post's Programme for the Ershov Hierarchy
This paper extends Post’s programme to finite levels of the Ershov hierarchy of ∆2 sets. Our initial characterisation, in the spirit of Post [27], of the degrees of the immune...
Bahareh Afshari, George Barmpalias, S. Barry Coope...
LOGCOM
2007
59views more  LOGCOM 2007»
13 years 11 months ago
Forgetting Literals with Varying Propositional Symbols
Recently, the old logical notion of forgetting propositional symbols (or reducing the logical vocabulary) has been generalized to a new notion: forgetting literals. The aim was to...
Yves Moinard
LOGCOM
2007
75views more  LOGCOM 2007»
13 years 11 months ago
The Extent of Constructive Game Labellings
We define a notion of combinatorial labellings, and show that ∆0 2 is the largest boldface pointclass in which every set admits a combinatorial labelling.
Benedikt Löwe, Brian Semmes
LOGCOM
2007
89views more  LOGCOM 2007»
13 years 11 months ago
Anytime Approximations of Classical Logic from Above
In this paper we present s1, a family of logics that is useful to disprove propositional formulas by means of an anytime approximation process. The systems follows the paradigm of...
Marcelo Finger, Renata Wassermann
LOGCOM
2007
130views more  LOGCOM 2007»
13 years 11 months ago
A Logic for Concepts and Similarity
Categorisation of objects into classes is currently supported by (at least) two ‘orthogonal’ methods. In logic-based approaches, classifications are defined through ontologi...
Mikhail Sheremet, Dmitry Tishkovsky, Frank Wolter,...
LOGCOM
2007
91views more  LOGCOM 2007»
13 years 11 months ago
Generalized Strong Preservation by Abstract Interpretation
Francesco Ranzato, Francesco Tapparo
LOGCOM
2007
115views more  LOGCOM 2007»
13 years 11 months ago
The Dynamics of Syntactic Knowledge
The syntactic approach to epistemic logic avoids the logical omniscience problem by taking knowledge as primary rather than as defined in terms of possible worlds. In this study, ...
Thomas Ågotnes, Natasha Alechina
LOGCOM
2007
125views more  LOGCOM 2007»
13 years 11 months ago
Epistemic Actions as Resources
We provide algebraic semantics together with a sound and complete sequent calculus for information update due to epistemic actions. This semantics is flexible enough to accommoda...
Alexandru Baltag, Bob Coecke, Mehrnoosh Sadrzadeh
LOGCOM
2007
74views more  LOGCOM 2007»
13 years 11 months ago
On Independence of Variants of the Weak Pigeonhole Principle
The principle sPHPa b (PV (α)) states that no oracle circuit can compute a surjection of a onto b. We show that sPHP (a) P (a)(PV (α)) is independent of PV1(α)+sPHP π(a) Π(a)...
Emil Jerábek
LOGCOM
2007
91views more  LOGCOM 2007»
13 years 11 months ago
A New Modal Approach to the Logic of Intervals
In Artificial Intelligence there is a need for reasoning about continuous processes, where assertions refer to time intervals rather than time points. Taking our lead from van Ben...
Altaf Hussain