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Category Archives: Infinite Group Theory
Infinite Commutativity (Part I)
The EckmannHilton Principle is a classical argument in algebraic topology/algebra. This argument allows you to conclude that an operation which may be expressed in two different ways (imagine that it may be applied both horizontally and vertically when written) is … Continue reading
What is an infinite word?
In this post, we’ll explore the idea of noncommutative infinitary operations on groups, that is, multiplying together infinitely many elements in a group. This idea arises very naturally in “wild” or “infinitary” algebraic topology. In fact, lately, this has been … Continue reading
The BaerSpecker Group
One of the infinite abelian groups that is important to infinite abelian group theory and which has shown up naturally in previous posts on infinitary fundamental groups is the BaerSpecker group, often just called the Specker group. This post isn’t … Continue reading