ELI5: Explain Like I'm 5

Arrow information paradox

Imagine you are playing a game where you shoot arrows at a target. While you are shooting, you notice that every time you shoot the arrow, it moves a little bit closer to the target. You keep shooting until the arrow finally hits the target.

Now, let's say that you want to figure out where the arrow is at any given moment as it moves toward the target. You might think that you can simply look at the arrow and see its position. However, the arrow is constantly moving, so its position is always changing.

This is where the arrow information paradox comes in. The paradox is that even though the arrow is always moving, and its position is always changing, we still have a sense of where the arrow is at any given moment.

So, how is it possible to know where the arrow is at any given moment, even though its position is always changing? The answer lies in the fact that we can calculate the arrow's position by using the information we have about where it was and how fast it was moving in the past.

For example, if we know that the arrow was at a particular position one second ago and was moving at a certain speed, we can estimate where it is now based on that information. By continuously updating our calculations with new information about the arrow's past movements, we can create a picture of where the arrow is at any given moment.

In summary, the arrow information paradox is the paradoxical idea that we can know the position of a constantly moving object, like an arrow, by using information about where it was and how fast it was moving in the past.