‎On The Spectrum of Countable MV-algebras

‎In this paper we consider MV-algebras and their prime spectrum‎. ‎We show that there is an uncountable MV-algebra that has the same spectrum as the free MV-algebra over one element‎, ‎that is‎, ‎the MV-algebra $Free_1$ of McNaughton functions from $[0,1]$ to $[0,1]$‎, ‎the continuous‎, ‎piecewise l...

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Main Author: Giacomo Lenzi
Format: Article
Language:English
Published: Islamic Azad University, Bandar Abbas Branch 2023-11-01
Series:Transactions on Fuzzy Sets and Systems
Subjects:
Online Access:https://tfss.journals.iau.ir/article_706608_43e7251b9559c462e5024531565ff316.pdf
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author Giacomo Lenzi
author_facet Giacomo Lenzi
author_sort Giacomo Lenzi
collection DOAJ
description ‎In this paper we consider MV-algebras and their prime spectrum‎. ‎We show that there is an uncountable MV-algebra that has the same spectrum as the free MV-algebra over one element‎, ‎that is‎, ‎the MV-algebra $Free_1$ of McNaughton functions from $[0,1]$ to $[0,1]$‎, ‎the continuous‎, ‎piecewise linear functions with integer coefficients‎. ‎The construction is heavily based on Mundici equivalence between MV-algebras and lattice ordered abelian groups with the strong unit‎. ‎Also‎, ‎we heavily use the fact that two MV-algebras have the same spectrum if and only if their lattice of principal ideals is isomorphic‎.‎As an intermediate step we consider the MV-algebra $A_1$ of continuous‎, ‎piecewise linear functions with rational coefficients‎. ‎It is known that $A_1$ contains $Free_1$‎, ‎and that $A_1$ and $Free_1$ are equispectral‎. ‎However‎, ‎$A_1$ is in some sense easy to work with than $Free_1$‎. Now‎, ‎$A_1$ is still countable‎. ‎To build an equispectral uncountable MV-algebra $A_2$‎, ‎we consider certain ``almost rational'' functions on $[0,1]$‎, ‎which are rational in every initial segment of $[0,1]$‎, ‎but which can have an irrational limit in $1$‎.‎We exploit heavily‎, ‎via Mundici equivalence‎, ‎the properties of divisible lattice ordered abelian groups‎, ‎which have an additional structure of vector spaces over the rational field‎.
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spelling doaj.art-bc7ff7b2ab704451a5d108f17fe2cc5b2023-11-03T11:15:29ZengIslamic Azad University, Bandar Abbas BranchTransactions on Fuzzy Sets and Systems2821-01312023-11-012218419310.30495/tfss.2023.1991906.1082706608‎On The Spectrum of Countable MV-algebrasGiacomo Lenzi0Department of Mathematics, University of Salerno, Fisciano (SA), Italy.‎In this paper we consider MV-algebras and their prime spectrum‎. ‎We show that there is an uncountable MV-algebra that has the same spectrum as the free MV-algebra over one element‎, ‎that is‎, ‎the MV-algebra $Free_1$ of McNaughton functions from $[0,1]$ to $[0,1]$‎, ‎the continuous‎, ‎piecewise linear functions with integer coefficients‎. ‎The construction is heavily based on Mundici equivalence between MV-algebras and lattice ordered abelian groups with the strong unit‎. ‎Also‎, ‎we heavily use the fact that two MV-algebras have the same spectrum if and only if their lattice of principal ideals is isomorphic‎.‎As an intermediate step we consider the MV-algebra $A_1$ of continuous‎, ‎piecewise linear functions with rational coefficients‎. ‎It is known that $A_1$ contains $Free_1$‎, ‎and that $A_1$ and $Free_1$ are equispectral‎. ‎However‎, ‎$A_1$ is in some sense easy to work with than $Free_1$‎. Now‎, ‎$A_1$ is still countable‎. ‎To build an equispectral uncountable MV-algebra $A_2$‎, ‎we consider certain ``almost rational'' functions on $[0,1]$‎, ‎which are rational in every initial segment of $[0,1]$‎, ‎but which can have an irrational limit in $1$‎.‎We exploit heavily‎, ‎via Mundici equivalence‎, ‎the properties of divisible lattice ordered abelian groups‎, ‎which have an additional structure of vector spaces over the rational field‎.https://tfss.journals.iau.ir/article_706608_43e7251b9559c462e5024531565ff316.pdfmv-algebras‎prime spectrum‎lattice ordered abelian groups‎
spellingShingle Giacomo Lenzi
‎On The Spectrum of Countable MV-algebras
Transactions on Fuzzy Sets and Systems
mv-algebras‎
prime spectrum‎
lattice ordered abelian groups‎
title ‎On The Spectrum of Countable MV-algebras
title_full ‎On The Spectrum of Countable MV-algebras
title_fullStr ‎On The Spectrum of Countable MV-algebras
title_full_unstemmed ‎On The Spectrum of Countable MV-algebras
title_short ‎On The Spectrum of Countable MV-algebras
title_sort ‎on the spectrum of countable mv algebras
topic mv-algebras‎
prime spectrum‎
lattice ordered abelian groups‎
url https://tfss.journals.iau.ir/article_706608_43e7251b9559c462e5024531565ff316.pdf
work_keys_str_mv AT giacomolenzi onthespectrumofcountablemvalgebras