## Functiones et Approximatio Commentarii Mathematici

### When does a closed ideal of a commutative unital Banach algebra contain a dense subideal?

Wiesław Żelazko

#### Abstract

The question formulated in the title is answered in the case of a separable algebra. The necessary and sufficient condition in this case is that the ideal in question is not finitely (algebraically) generated. We conjecture that this result is true in the general case.

#### Article information

Source
Funct. Approx. Comment. Math., Volume 44, Number 2 (2011), 285-287.

Dates
First available in Project Euclid: 22 June 2011

https://projecteuclid.org/euclid.facm/1308749132

Digital Object Identifier
doi:10.7169/facm/1308749132

Mathematical Reviews number (MathSciNet)
MR2841187

Zentralblatt MATH identifier
1230.46047

Subjects
Primary: 46J20: Ideals, maximal ideals, boundaries

Keywords
Banach algebra dense subideal

#### Citation

Żelazko, Wiesław. When does a closed ideal of a commutative unital Banach algebra contain a dense subideal?. Funct. Approx. Comment. Math. 44 (2011), no. 2, 285--287. doi:10.7169/facm/1308749132. https://projecteuclid.org/euclid.facm/1308749132

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