ELI5: Explain Like I'm 5

Reflexive space

So, you know how when you look in a mirror, you can see yourself? That's kind of like what a reflexive space is. It's a space, but with a fancy name, where points can look at themselves in a way - but instead of a mirror, they use a special mathematical tool called a map.

Here's an example: imagine you're standing on a big flat field. You want to figure out how far away a tree is from you. You could use a measuring tape to measure the distance between you and the tree, right? But what if you didn't have a measuring tape? What if you only had a map that showed the field, and a way to measure angles between things?

That's where reflexive spaces come in. They're spaces where you can use a special kind of map called a norm, which tells you how long things are within the space. Using this norm, you can figure out how far away things are from each other without actually having to measure the distance. And the cool thing is that each point in the space can "look at" itself in the map and figure out how far away it is from other points.

So, a reflexive space is kind of like a big field where all the points have a special tool that lets them "see" themselves and know how far away they are from other points without having to measure it with a tape. Pretty neat, right?
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