No : 6 Title : ‘ E * - Dense E - Semigroups ’ Author ( S )
نویسندگان
چکیده
We obtain a covering theorem for E∗-dense E-semigroups showing that such a semigroup has an E∗-dense, strongly E∗-unitary E-semigroup as a cover and describe the structure of the latter semigroups.
منابع مشابه
On strongly dense submodules
The submodules with the property of the title ( a submodule $N$ of an $R$-module $M$ is called strongly dense in $M$, denoted by $Nleq_{sd}M$, if for any index set $I$, $prod _{I}Nleq_{d}prod _{I}M$) are introduced and fully investigated. It is shown that for each submodule $N$ of $M$ there exists the smallest subset $D'subseteq M$ such that $N+D'$ is a strongly dense submodule of $M$ and $D'bi...
متن کاملSemigroups with inverse skeletons and Zappa-Sz$acute{rm e}$p products
The aim of this paper is to study semigroups possessing $E$-regular elements, where an element $a$ of a semigroup $S$ is {em $E$-regular} if $a$ has an inverse $a^circ$ such that $aa^circ,a^circ a$ lie in $ Esubseteq E(S)$. Where $S$ possesses `enough' (in a precisely defined way) $E$-regular elements, analogues of Green's lemmas and even of Green's theorem hold, where Green's relations ${mathc...
متن کاملRees Matrix Covers and Semidirect Products of Regular Semigroups
In a recent paper, P.G. Trotter and the author introduced a \regular" semidirect product UV of e-varieties U and V. Among several speciic situations investigated there was the case V = RZ, the e-variety of right zero semigroups. Applying a covering theorem of McAlister, it was shown there that in several important cases (for instance for the e-variety of inverse semigroups), U RZ is precisely t...
متن کاملSemigroups whose idempotents form a subsemigroup ∗
We prove that every semigroup S in which the idempotents form a sub-semigroup has an E-unitary cover with the same property. Furthermore, if S is E-dense or orthodox, then its cover can be chosen with the same property. Then we describe the structure of E-unitary dense semigroups. Our results generalize Fountain's results on semigroups in which the idempotents commute, and are analogous to thos...
متن کاملNo : 11 Title : ‘ Primitive Inverse Semigroups of Left I - Quotients ’ Author ( S ) :
A subsemigroup S of an inverse semigroup Q is a left I-order in Q, if every element in Q can be written as a−1b where a, b ∈ S and a−1 is the inverse of a in the sense of inverse semigroup theory. We study a characterisation of semigroups which have a primitive inverse semigroup of left I-quotients.
متن کامل