Fixed points and unfounded chains
β Scribed by Claudio Bernardi
- Book ID
- 104307094
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 143 KB
- Volume
- 109
- Category
- Article
- ISSN
- 0168-0072
No coin nor oath required. For personal study only.
β¦ Synopsis
By an unfounded chain for a function f : X β X we mean a sequence (xn)nβ! of elements of X s.t. fxn+1 = xn for every n. Unfounded chains can be regarded as a generalization of ΓΏxed points, but on the other hand are linked with concepts concerning non-well-founded situations, as ungrounded sentences and the hypergame. In this paper, among other things, we prove a lemma in general topology, we exhibit an extensional recursive function from the set of sentences of PA into itself without an unfounded chain, and we prove that every term in a Magari algebra (or diagonalizable algebra) has an unfounded chain.
π SIMILAR VOLUMES
Our purpose is to present some connections between modal incompleteness and modal logics related to the GΓΆdel-LΓΆb logic GL. One of our goals is to prove that for all is incomplete and does not have the fixed point property. As a consequence we shall obtain that the Boolos logic KH does not have the