Another level, "Ultimate Ensemble" explains that all models coexist, described by mathematical structures.
The observable universe is about 90 billion light years across but it is hard to tell how much further the universe expands from there
We continue to work on expanding our views on the universe that we can see and try to reach out further
We also run into the problem called the "anthropic principle" which means that our universe is specialized for human life, most likely unlike other parallel universes.
The name "multiverse" was made up by William James in 1895 to describe the complexities of natural phenomena
1952, Erwin Schrödinger's equations pointed towards multiple histories that happened simultaneously
But as long as we're stuck in this universe, let's just hope that 2020 can get a little better!
Works CitedAguirre, A. (2019, November 28). Multiverse. Retrieved from https://www.britannica.com/science/multiverseMinute Physics. [minutephysics]. (2013, Apr 2). The True Science of Parallel Universes [Video]. Youtube. https://www.youtube.com/watch?v=Ywn2Lz5zmYgMultiverse. (2020, June 3). Retrieved from https://en.wikipedia.org/wiki/MultiverseSiegel, E. (2019, March 15). This Is Why The Multiverse Must Exist. Retrieved June 7, 2020, from https://www.forbes.com/sites/startswithabang/2019/03/15/this-is-why-the-multiverse-must-exist/#12934ac66d08The Economist. [The Economist]. (2015, Aug 14). Do we live in a multiverse? [Video]. Youtube. https://www.youtube.com/watch?v=Rx7erWZ8TjA