On the structure of the integral green ring of a cyclic group of order p2

1986 ◽  
pp. 98-108
Author(s):  
A. Jones ◽  
G. O. Michler
Keyword(s):  
Cyclic Group ◽  
Green Ring

scholarly journals A CRITERION FOR THE JACOBSON SEMISIMPLICITY OF THE GREEN RING OF A FINITE TENSOR CATEGORY

2017 ◽  
Vol 60 (1) ◽  
pp. 253-272 ◽  
Author(s):  
ZHIHUA WANG ◽  
LIBIN LI ◽  
YINHUO ZHANG
Keyword(s):  
Cyclic Group ◽  
Jacobson Radical ◽  
Tensor Category ◽  
Closed Field ◽  
Algebraically Closed Field ◽  
Green Ring ◽  
Isomorphism Classes

AbstractThis paper deals with the Green ring $\mathcal{G}(\mathcal{C})$ of a finite tensor category $\mathcal{C}$ with finitely many isomorphism classes of indecomposable objects over an algebraically closed field. The first part of this paper deals with the question of when the Green ring $\mathcal{G}(\mathcal{C})$, or the Green algebra $\mathcal{G}(\mathcal{C})\otimes_{\mathbb {Z}}$K over a field K, is Jacobson semisimple (namely, has zero Jacobson radical). It turns out that $\mathcal{G}(\mathcal{C})\otimes_{\mathbb {Z}}$K is Jacobson semisimple if and only if the Casimir number of $\mathcal{C}$ is not zero in K. For the Green ring $\mathcal{G}(\mathcal{C})$ itself, $\mathcal{G}(\mathcal{C})$ is Jacobson semisimple if and only if the Casimir number of $\mathcal{C}$ is not zero. The second part of this paper focuses on the case where $\mathcal{C}=\text{Rep}(\mathbb {k}G)$ for a cyclic group G of order p over a field $\mathbb {k}$ of characteristic p. In this case, the Casimir number of $\mathcal{C}$ is computable and is shown to be 2p2. This leads to a complete description of the Jacobson radical of the Green algebra $\mathcal{G}(\mathcal{C})\otimes_{\mathbb {Z}}$K over any field K.

scholarly journals Commutative semigroups whose endomorphisms are power functions

2021 ◽  
Author(s):  
Ryszard Mazurek
Keyword(s):  
Positive Integer ◽  
Power Function ◽  
Cyclic Group ◽  
Commutative Semigroup ◽  
Commutative Monoid ◽  
Power Functions ◽  
Commutative Semigroups ◽  
Finite Cyclic Group

AbstractFor any commutative semigroup S and positive integer m the power function $$f: S \rightarrow S$$ f : S → S defined by $$f(x) = x^m$$ f ( x ) = x m is an endomorphism of S. We partly solve the Lesokhin–Oman problem of characterizing the commutative semigroups whose all endomorphisms are power functions. Namely, we prove that every endomorphism of a commutative monoid S is a power function if and only if S is a finite cyclic group, and that every endomorphism of a commutative ACCP-semigroup S with an idempotent is a power function if and only if S is a finite cyclic semigroup. Furthermore, we prove that every endomorphism of a nontrivial commutative atomic monoid S with 0, preserving 0 and 1, is a power function if and only if either S is a finite cyclic group with zero adjoined or S is a cyclic nilsemigroup with identity adjoined. We also prove that every endomorphism of a 2-generated commutative semigroup S without idempotents is a power function if and only if S is a subsemigroup of the infinite cyclic semigroup.

On the Uniqueness of the Cyclic Group of Order n

1992 ◽  
Vol 99 (6) ◽  
pp. 545-547 ◽  
Author(s):  
Dieter Jungnickel
Keyword(s):  
Cyclic Group

scholarly journals A note on frame starters

1996 ◽  
Vol 53 (2) ◽  
pp. 293-297
Author(s):  
Cheng-De Wang
Keyword(s):  
Cyclic Group ◽  
Unique Element ◽  
Left Frame

We construct frame starters in Z2n − {0, n}, for n ≡ 0, 1 mod 4, where Z2n denotes the cyclic group of order 2n. We also construct left frame starters in Q2n − {e, αn}, where Q2n is the dicyclic group of order 4n and αn is the unique element of order 2 in Q2n.

Groups with a Cyclic Group as Lattice-Homomorph

1948 ◽  
Vol 49 (2) ◽  
pp. 347
Author(s):  
Philip M. Whitman
Keyword(s):  
Cyclic Group
Sign in / Sign up

Export Citation Format

Share Document