| Title:
             | 
Adjoint Semilattice and Minimal Brouwerian Extensions of a Hilbert Algebra (English) | 
| Author:
             | 
Cīrulis, Jānis | 
| Language:
             | 
English | 
| Journal:
             | 
Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica | 
| ISSN:
             | 
0231-9721 | 
| Volume:
             | 
51 | 
| Issue:
             | 
2 | 
| Year:
             | 
2012 | 
| Pages:
             | 
41-51 | 
| Summary lang:
             | 
English | 
| . | 
| Category:
             | 
math | 
| . | 
| Summary:
             | 
Let $A := (A,\rightarrow ,1)$ be a Hilbert algebra. The monoid of all unary operations on $A$ generated by operations $\alpha _p\colon x \mapsto (p \rightarrow x)$, which is actually an upper semilattice w.r.t. the pointwise ordering, is called the adjoint semilattice of $A$. This semilattice is isomorphic to the semilattice of finitely generated filters of $A$, it is subtractive (i.e., dually implicative), and its ideal lattice is isomorphic to the filter lattice of $A$. Moreover, the order dual of the adjoint semilattice is a minimal Brouwerian extension of $A$, and the embedding of $A$ into this extension preserves all existing joins and certain “compatible” meets. (English) | 
| Keyword:
             | 
adjoint semilattice | 
| Keyword:
             | 
Brouwerian extension | 
| Keyword:
             | 
closure endomorphism | 
| Keyword:
             | 
compatible meet | 
| Keyword:
             | 
filter | 
| Keyword:
             | 
Hilbert algebra | 
| Keyword:
             | 
implicative semilattice | 
| Keyword:
             | 
subtraction | 
| MSC:
             | 
03G25 | 
| MSC:
             | 
06A12 | 
| MSC:
             | 
06A15 | 
| MSC:
             | 
08A35 | 
| idZBL:
             | 
Zbl 06204929 | 
| idMR:
             | 
MR3058872 | 
| . | 
| Date available:
             | 
2012-11-26T10:16:42Z | 
| Last updated:
             | 
2014-03-12 | 
| Stable URL:
             | 
http://hdl.handle.net/10338.dmlcz/143066 | 
| . | 
| Reference:
             | 
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| Reference:
             | 
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| Reference:
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