The isomorphism theorem of measure theory for atomic measures.

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There is the famous isomorphism theorem for measure spaces:

All separable nonatomic normalized measure algebras are mutually isomorphic.

what about an atomic normalized measure algebras?

Is it possible to establish an isomorphism or a measure-preserving transformation from an atomic normalized measure algebra into the measure algebra of the unit interval?

These theorems would be helpful in understanding my qeustion. enter image description here enter image description here Any help would be appreciated.

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$\def\ed{\stackrel{\text{def}}{=}}$ Suggestion

Let $\ (\mathscr{A},\mu)\ $ be a normalised atomic measure algebra with atoms $\ a_1,a_2,\dots\ $ of weights $\ w_1\ed\mu\big(a_1\big),w_2\ed\mu\big(a_2\big),\dots $ respectively, $\ (\mathbf{T},\nu)\ $ the measure algebra of the unit interval, $\ w_0\ed0\ $, and for each $\ i\ $ $\ \alpha_i\in\mathbf{T}\ $ be the class of Lebesgue measurable sets equivalent to the interval $\ \left[\sum_\limits{j=0}^{i-1}w_j,\sum_\limits{j=0}^iw_j\right]\ $. Then $\ \nu\big(\alpha_i\big)=w_i=\mu\big(a_i\big)\ $, and it looks to me like the measure algebra generated by $\ \alpha_1, \alpha_2,\dots\ $ should be isomorphic to $\ \mathscr{A}\ $ (but I haven't done all the i-dotting and t-crossing necessary to prove it.)

Reply to query from OP in comments below

On rereading this comment, it looks like I initially misunderstood it. It now appears to me to be asking how to construct the isomorphism referred to in my answer above.

Since $\ (\mathscr{A},\mu)\ $ is an atomic normalised measure algebra, any element $\ a\ $ of $\ \mathscr{A}\ $ can be expressed uniquely as a countable join $$ a=\bigvee_{\big\{i\in\mathbb{N}\,\big|\,\mu\big(a\wedge a_i\big)>0\big\}}a_i $$ of atoms of $\ (\mathscr{A},\mu)\ $. The assignment $$ a\mapsto \bigvee_{\big\{i\in\mathbb{N}\,\big|\,\mu\big(a\wedge a_i\big)>0\big\}}\alpha_i $$ will then give an isomorphism of $\ (\mathscr{A},\mu)\ $ to the subalgebra of $\ (\mathbf{T},\nu)\ $ generated by $\ \alpha_1, \alpha_2,\dots\ $.