## Banach Journal of Mathematical Analysis

### Maximal ideal space of some Banach algebras and related problems

#### Abstract

Let $C_{A}^{\left( n\right) }:=C_{A}^{\left( n\right) }\left( \mathbb{D}\times\mathbb{D}\right)$ denote the subspace of functions in the Banach space $C^{\left( n\right) }\left( \overline{\mathbb{D}% \times\mathbb{D}}\right)$ which are analytic in the bi-disc $\mathbb{D}% \times\mathbb{D}$. We consider the subspace $B_{zw}$ consisting from the functions $f\in C_{A}^{\left( n\right) }$ which can be represented in the form $f\left( z,w\right) =g\left( zw\right) ,$ where $g$ is a single variable function from the disc algebra $C_{A}\left( \mathbb{D}\right)$. We prove that $B_{zw}$ is a Banach algebra under the Duhamel multiplication $\left( f\circledast g\right) \left( zw\right) =\frac{\partial^{2}% }{\partial z\partial w}\underset{0}{\overset{z}{\int}}\underset{0}{\overset {w}{\int}}f\left( \left( z-u\right) \left( w-v\right) \right) g\left( uv\right) dvdu$ and describe its maximal ideal space. We also consider the Hardy type operator $f\rightarrow xy\underset{0}{\overset{x}{\int}}\underset{0}{\overset{y}{\int}% }f\left( t\tau\right) d\tau dt$ and discuss its some properties.

#### Article information

Source
Banach J. Math. Anal., Volume 8, Number 2 (2014), 16-29.

Dates
First available in Project Euclid: 4 April 2014

https://projecteuclid.org/euclid.bjma/1396640048

Digital Object Identifier
doi:10.15352/bjma/1396640048

Mathematical Reviews number (MathSciNet)
MR3189535

Zentralblatt MATH identifier
1308.47045

#### Citation

Saltan, Suna; Özel, Yasem. Maximal ideal space of some Banach algebras and related problems. Banach J. Math. Anal. 8 (2014), no. 2, 16--29. doi:10.15352/bjma/1396640048. https://projecteuclid.org/euclid.bjma/1396640048

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