Introduction to Group Theory by Ledermann and Weir

Introduction to Group Theory by Ledermann and Weir

Ledermann and Weir take a slightly unique approach in the theory of groups. Their text is slightly difficult to follow in a lot of places as they tend to group things together in non-standard ways. The biggest difference I found with his use of symbols is when talking about homomorphisms. In particular most texts will look at a homomorphism: $$\theta : G \rightarrow G^{\prime}$$ and when going from $$G$$ to $$G^{\prime}$$ they apply a function such as $$\theta (g)$$; Ledermann and Weird on the other hand choose to use the notation of $$g\theta$$. Although this format might be more concise, it can at times be a little confusing as to what each symbol is supposed to stand for. My assumption is that he’s trying to show that a homomorphism is similar to group actions with the action being the map $$\theta$$, but for an introductory piece, it can be particularly confusing.