Idempotents in an ultrametric Banach algebra
نویسندگان
چکیده
Let IK be a complete ultrametric field and let A unital commutative Banach IK-algebra. Suppose that the multiplicative spectrum admits partition in two open closed subsets. Then there exist unique idempotents u, v ϵ such Ï (u) = 1, (v) 0 â U, 1 V . is algebraically closed. If an element x has empty annulus r < |ξ â a| s its sp(x), then 1; whenever (x a) ⤠0; ⥠s.
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ژورنال
عنوان ژورنال: Cubo
سال: 2021
ISSN: ['0716-7776', '0719-0646']
DOI: https://doi.org/10.4067/s0719-06462021000100161