scholarly journals A characterization of locally finite varieties that satisfy a nontrivial congruence identity

1999 ◽  
Vol 42 (3) ◽  
pp. 195-204 ◽  
Author(s):  
Keith A. Kearnes
1996 ◽  
Vol 39 (3) ◽  
pp. 308-315 ◽  
Author(s):  
Paolo Lipparini

AbstractWe characterize, by means of congruence identities, all varieties having a weak difference term, and all neutral varieties. Our characterization of varieties with a difference term is new even in the particular case of locally finite varieties.


1997 ◽  
Vol 349 (5) ◽  
pp. 1749-1768 ◽  
Author(s):  
Keith A. Kearnes ◽  
Ágnes Szendrei

2018 ◽  
Vol 79 (3) ◽  
Author(s):  
Nemanja Draganić ◽  
Petar Marković ◽  
Vlado Uljarević ◽  
Samir Zahirović

1991 ◽  
Vol 140 (2) ◽  
pp. 362-369 ◽  
Author(s):  
Matthew A. Valeriote ◽  
Ross Willard

2016 ◽  
Vol 15 (08) ◽  
pp. 1650149 ◽  
Author(s):  
Said El Baghdadi ◽  
Marco Fontana ◽  
Muhammad Zafrullah

Let [Formula: see text] be an integral domain with quotient field [Formula: see text]. Call an overring [Formula: see text] of [Formula: see text] a subring of [Formula: see text] containing [Formula: see text] as a subring. A family [Formula: see text] of overrings of [Formula: see text] is called a defining family of [Formula: see text], if [Formula: see text]. Call an overring [Formula: see text] a sublocalization of [Formula: see text], if [Formula: see text] has a defining family consisting of rings of fractions of [Formula: see text]. Sublocalizations and their intersections exhibit interesting examples of semistar or star operations [D. D. Anderson, Star operations induced by overrings, Comm. Algebra 16 (1988) 2535–2553]. We show as a consequence of our work that domains that are locally finite intersections of Prüfer [Formula: see text]-multiplication (respectively, Mori) sublocalizations turn out to be Prüfer [Formula: see text]-multiplication domains (PvMDs) (respectively, Mori); in particular, for the Mori domain case, we reobtain a special case of Théorème 1 of [J. Querré, Intersections d’anneaux intègers, J. Algebra 43 (1976) 55–60] and Proposition 3.2 of [N. Dessagnes, Intersections d’anneaux de Mori — exemples, Port. Math. 44 (1987) 379–392]. We also show that, more than the finite character of the defining family, it is the finite character of the star operation induced by the defining family that causes the interesting results. As a particular case of this theory, we provide a purely algebraic approach for characterizing P vMDs as a subclass of the class of essential domains (see also Theorem 2.4 of [C. A. Finocchiaro and F. Tartarone, On a topological characterization of Prüfer [Formula: see text]-multiplication domains among essential domains, preprint (2014), arXiv:1410.4037]).


2020 ◽  
Vol 57 (3) ◽  
pp. 284-289
Author(s):  
Paolo Lipparini

AbstractWe provide a Maltsev characterization of congruence distributive varieties by showing that a variety 𝓥 is congruence distributive if and only if the congruence identity … (k factors) holds in 𝓥, for some natural number k.


2021 ◽  
Vol 38 (1) ◽  
pp. 223-230
Author(s):  
MIHAIL URSUL ◽  
◽  
JOHN LANTA ◽  

We study in this paper conditions under which nilradicals of totally disconnected locally compact rings are closed. In the paper is given a characterization of locally finite compact rings via identities.


Sign in / Sign up

Export Citation Format

Share Document