The idea that you have a personal universe is not something you’ll see in the scientific literature. There is no part of your brain that cognitive scientists can point to and say “this houses your personal universe.”
“Personal universe” is a frame. A metaphor. It connects two realms that seem very distant: you as an individual person and the cosmos. It says that you are responsible for your tiny part of the universe.
It’s also a way to look at who you are in terms of something you possess, have control over and are responsible for. It disentangles who you are from how you feel right now and what you think you should be. It allows you to look at yourself more objectively. It puts you in control.
Maybe you believe that you can’t change who you are. Maybe you’ve been told that you can’t change your worldview.
But you can make your personal universe more flexible, accurate, expansive and integrated. You can strengthen your personal universe, and that process will change you.