Abstract
Let A be a complex unital Banach algebra and let R ⊂ A be a non-empty set. This paper defines the property such that R is closed for idempotent decomposition (in short, (CID) property) to explore the spectral decomposition relation. Further, for an upper semiregularity R with (CID) property, RD is constructed as an extension of R to axiomatically study the accumulation of σR(a) for any a ∈A. At last, several illustrative examples on Banach algebra and operator algebra are provided.
| Original language | English |
|---|---|
| Pages (from-to) | 777-792 |
| Number of pages | 16 |
| Journal | Forum Mathematicum |
| Volume | 37 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 1 May 2025 |
Keywords
- Banach algebra
- Idempotent decomposition
- regularity
- spectrum