Studies in Rings generalised Unique Factorisation Rings
Studies in Rings generalised Unique Factorisation Rings
Studies in Rings generalised Unique Factorisation Rings
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Def<strong>in</strong>ition 1 054.<br />
Let A be a" right R-module and B a submodule of A.<br />
B is said to be an essential submodule of A if B ne 1= o.<br />
for every non zero submodule C of A.<br />
Def<strong>in</strong>ition 1.55 ..<br />
Let Q be a r<strong>in</strong>g. A right order <strong>in</strong> Q is any subr<strong>in</strong>g<br />
R ~ Q such that<br />
(a)<br />
(b)<br />
Every regular element of R is <strong>in</strong>vertible <strong>in</strong> Q<br />
-1<br />
Every element of Q has the form ab for some<br />
a ~ R and some regular element b <strong>in</strong> R.<br />
It is clear that the r<strong>in</strong>g Q <strong>in</strong> the def<strong>in</strong>ition 1055<br />
and the localization of the r<strong>in</strong>g R at the multiplicative<br />
set CR(O)<br />
are same.<br />
Remark 1.56.<br />
A right Goldie r<strong>in</strong>g is any r<strong>in</strong>g R,<br />
such that R has<br />
f<strong>in</strong>ite right rank and ACe on right annihilators. Thus<br />
every righ.t Noe the r i an 4I'hg is righ t Goldie.<br />
Remark 1057.<br />
Goldie ha s proved that <strong>in</strong> a semiprime right Goldie r<strong>in</strong>g<br />
every essential. right ideal conta<strong>in</strong>s a<br />
regular element and