So I am not a physicist or have any background in physics but I enjoy thought experiments and thinking about the nature of our universe and I was thinking about the idea that we live in a multiverse where every possible decision is made in all of it's possible variations and I'm confused how this correlates with the law of conservation of energy.
Since it's easy to assume this type of multiverse branches out and grows at an exponential rate then shouldn't we observe a matching exponential loss of energy from our universe? Either the energy for this new universe had to be created from nothing which is in violation of the law or the energy from the previously existing universe would need to be divided between the newly created universe and the existing universe resulting in an observable loss of energy.
One thought that I have is that if time is in fact the 4th dimension then the future must be as concrete as the past (any point in time just an index along a dimensional axis) which would mean that the future is predetermined and all possible multiverses existed at the moment of the big bang and all of the energy was divided at that time. That would mean while we like the perceive that we made a decision and that decision branched out a new universe that perception is false. While in reality we always made that same "decision" and what we perceived to be a new universe always existed because our decision was predetermined and nothing was ever variable.
This all started with me doing a thought experiment into if we have free will or not which leads me here. Now I'm thinking that for everything to make sense 1) we don't have free will (not that it changes anything) 2) The multiverse exists as a immutable entity where every branch of the multiverse was created in all the infinite variations simultaneously.