We consider some problems of spectral analysis and spectral synthesis in the topological vector space M(G)\documentclass[12pt]{minimal}
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\begin{document}$${{\mathcal {M}}}(G)$$\end{document} of tempered functions on a discrete Abelian group G. It is proved that spectral analysis holds in the space M(G)\documentclass[12pt]{minimal}
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\begin{document}$${{\mathcal {M}}}(G)$$\end{document} on every Abelian group G, that is, every nonzero closed linear translation invariant subspace of M(G)\documentclass[12pt]{minimal}
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\begin{document}$${{\mathcal {M}}}(G)$$\end{document} contains an exponential. For any finitely generated Abelian group G it is proved, that spectral synthesis holds in M(G)\documentclass[12pt]{minimal}
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\begin{document}$${{\mathcal {M}}}(G)$$\end{document}, that is, every closed linear translation invariant subspace H\documentclass[12pt]{minimal}
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\begin{document}$${{\mathscr {H}}}$$\end{document} of M(G)\documentclass[12pt]{minimal}
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\begin{document}$${{\mathcal {M}}}(G)$$\end{document} coincides with the closed linear span of all exponential monomials belonging to H\documentclass[12pt]{minimal}
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\begin{document}$${{\mathscr {H}}}$$\end{document}. For any Abelian group G with infinite torsion free rank it is proved that spectral synthesis fails to hold in the space M(G)\documentclass[12pt]{minimal}
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\begin{document}$${{\mathcal {M}}}(G)$$\end{document}.