Let a setC be given. Two subsets S,T ⊆ C are said to be orthogonal, written S ⊥ T, if S ∩ T is ∅ or a singleton. For a family of C-sets (i.e., F ⊆ ℘(C)), the dual of F, written F⊥, is defined as the set of all C-sets S such that for every T ∈ F, S ⊥ T. A coherent spaceF over C is a family C-sets for which F = (F⊥) ⊥.
References
Girard J-Y, Lafont Y, Taylor P, Proofs and types, Cambridge Press 1989
Girard J-Y, Between logic and quantic: a tract (http://iml.univ-mrs.fr/~girard/Articles.html), manuscript December 2003
In mathematics, especially in algebraic geometry and the theory of complex manifolds, a coherent sheaf F on a locally ringed space X is a sheaf isomorphic with the cokernel of a morphism of O
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Space is an area where the added value of a joint and coherent policy on the European level is very clear.
The European space programme, to be defined in concept by the end of 2005, will constitute a common, inclusive and flexible platform encompassing all activities and measures to be undertaken by the EC, ESA and other stakeholders (e.g.
To this end, a second "Space Council" meeting is planned for Spring 2005 to define general governance principles, identify priorities as well as the roles and responsibilities of all stakeholders and establish industrial policy principles.
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