[kisoron-ml] JAIST Logic Seminar Series

[Hajime Ishihara]

皆様

ジーゲン大学のDieter Spreen先生の講演のお知らせです。
どうぞふるってご参加ください。

問合せ先：
石原　哉
北陸先端科学技術大学院大学 情報科学研究科
e-mail: ishihara at jaist.ac.jp

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* JAIST Logic Seminar Series *

* This seminar is held as a part of JSPS Core-to-Core Program,
A. Advanced Research Networks, and EU FP7 Marie Curie Actions
IRSES project COMPUTAL (http://computal.uni-trier.de/).

Date: Thursday 7 May, 2015, 13:30-15:00

Place: JAIST, Collaboration room 6 (I-57g)
(Access: http://www.jaist.ac.jp/english/location/access.html)

Speaker: Dieter Spreen (University of Siegen)

Title:  Digit Spaces - Topological Foundations
Abstract:
Digit spaces have been introduced by Ulrich Berger as a framework for 
extracting programs that deal with continuous data from formal proofs.
The essential idea was to represent objects as streams of unary 
contractions on a complete metric space and to use coinduction on the 
logical side.
In recent joint work on an extension of this approach to hyperspaces 
like the space of nonempty compact subsets of a digit space,
it turned out that compact cannot be represented by such streams in 
general: instead one has to deal with infinite trees the nodes of which 
are labeled by
contraction similar to the stream case.
It was realized, however, that one will obtain a uniform theory, if the 
contractions, also called digits, are allowed to be multi-ary.