According to Hugh Everett's interpretation of the quantum-mechanical "Schrödinger's cat" paradox, (when does a quantum system stop existing as a superposition of states and become one or the other?) every event is a branch point.
Before you open the box cat is both alive and dead. When you open the box you experience one or the other outcome.
Irrespective of when the box is opened, both the "alive" and "dead" cats exist but due to "many-worlds" are in different branches of the universe, exist in parallel worlds. Both of which are equally real, but which cannot interact with each other.
You are stuck in the box.
You need to stop trying to experience all possible alternative histories and futures and decide on one course of action.
