Dehn twist
Imagine you have a rubber band in your hand. Now imagine you twist your wrist while holding the rubber band. This is kind of like what a dehn twist is.
But instead of a rubber band, we're talking about a shape called a "loop" or "circle" that's drawn on a piece of paper. A dehn twist is when you imagine grabbing one part of the circle and twisting it, like you're twisting the rubber band.
But here's the tricky part - this twisted circle is actually in a really special 3-dimensional shape called a "manifold". This means that the shape is kind of like spaghetti noodles all twisted up and connected in different ways.
By doing a dehn twist on this circle in the manifold, we can change the way the noodles are twisted and connected. This can tell us some really interesting things about the structure of the manifold!
But instead of a rubber band, we're talking about a shape called a "loop" or "circle" that's drawn on a piece of paper. A dehn twist is when you imagine grabbing one part of the circle and twisting it, like you're twisting the rubber band.
But here's the tricky part - this twisted circle is actually in a really special 3-dimensional shape called a "manifold". This means that the shape is kind of like spaghetti noodles all twisted up and connected in different ways.
By doing a dehn twist on this circle in the manifold, we can change the way the noodles are twisted and connected. This can tell us some really interesting things about the structure of the manifold!
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