W sobotę 20 października 2007 roku odbyła się specjalna sesja PTLiFN z okazji
85-tych urodzin Profesora Andrzeja Grzegorczyka.
Referaty wygłosili:
1. Peter Hajek, „Mathematical fuzzy logic and natural numbers”.
Abstract: The basic fuzzy (predicate) logic BL\forall will be shortly presented. A weak variant of Robinson arithmetic with addition and multiplication as ternary relations (a fuzzy variant of a rather weak arithmetic investigated by Grzegorczyk) is investigated over the fuzzy logic BL\forall. Essential undecidability is proved by a careful analysis of the classical proof of essential undecidability of arithmetic.
2. BalderTen Cate, „Grzegorczyk with applications to XML”
Abstract: This talk is about a logic introduced by Grzegorczyk in the 1960s, commonly referred to in the modal logic literature as „Grzegorczyk’s logic” or Grz. This logic turns out to be relevant for XML applications: it is an elegant and surprisingly well behaved fragment of the XML path language XPath. I’ll discuss how some of the things we know about Grz tell us something new about XPath.
W czasie spotkania wręczono profesorowi Grzegorczykowi dedykowany mu tom specjalny Fundamenta Informaticae.
Jubilatowi składamy najserdeczniejsze życzenia zdrowia i dalszych sukcesów List_gratulacyjny.
