ELI5: Explain Like I'm 5

Locally cyclic group

Okay, so let's start with a group. A group is kind of like a club where all members follow some rules. There are many rules that can be followed, but one important rule is that every member in the club should have a friend. And when I say every member, I mean every single one!

Now let's talk about a locally cyclic group. Imagine you have a group of friends, but not all of them follow the rule of having a friend. Some members have friends, while others don't. However, if you zoom in on any one person who doesn't have a friend, you can still find a small group of friends around them who follow that rule.

A locally cyclic group is kind of like that. It's a group where not all members follow a certain rule, but if you zoom in on any one member, you can find a small group of members who do follow that rule. And the rule that a locally cyclic group follows is that every member has a special "number" that they can use to do some math.

So if you have a group that is locally cyclic, it means that not all members can use their special numbers to do math in the same way, but if you zoom in on any one member, you can find a small group of members who can use their special numbers in a similar way. And that's pretty cool, don't you think?