ELI5: Explain Like I'm 5

Apollonian circles

Apollonian circles are like a game where we take a circle and then draw a tangent line to it. This creates a new circle that touches the original circle at the point where we drew the tangent line. We can keep playing this game as many times as we want, drawing tangent lines to the previous circles and creating new circles.

Now the cool thing about Apollonian circles is that if we keep playing this game forever, the circles created will eventually get smaller and smaller and fill up all the space inside the original circle. This means that every single point in the circle can be touched by one of the Apollonian circles we created.

In math, we use special equations to describe these circles, but we don't need to worry about that right now. The important thing to remember is that Apollonian circles are like a fun game where we use circles and tangent lines to fill up all the space inside the circle.
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