## Publicacions Matemàtiques

### Conjugacy classes of left ideals of a finite dimensional algebra

#### Abstract

Let $A$ be a finite dimensional unital algebra over a field $K$ and let $C(A)$ denote the set of conjugacy classes of left ideals in $A$. It is shown that $C(A)$ is finite if and only if the number of conjugacy classes of nilpotent left ideals in $A$ is finite. The set~$C(A)$ can be considered as a semigroup under the natural operation induced from the multiplication in $A$. If $K$ is algebraically closed, the square of the radical of~$A$ is zero and $C(A)$ is finite, then for every $K$-algebra $B$ such that $C(B)\cong C(A)$ it is shown that $B\cong A$.

#### Article information

Source
Publ. Mat., Volume 57, Number 2 (2013), 477-496.

Dates
First available in Project Euclid: 12 December 2013

https://projecteuclid.org/euclid.pm/1386857705

Mathematical Reviews number (MathSciNet)
MR3114779

Zentralblatt MATH identifier
1292.16013

#### Citation

Mȩcel, Arkadiusz; Okniński, Jan. Conjugacy classes of left ideals of a finite dimensional algebra. Publ. Mat. 57 (2013), no. 2, 477--496. https://projecteuclid.org/euclid.pm/1386857705

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