In a recent cosmology discussion group, a paper by Jean-Luc Lehners and Jerome Quintin titled “A small Universe” was explored. The prevailing assumption in many cosmological models is that the universe is infinite or incredibly vast. However, the authors argue that the universe could actually be relatively small, not much larger than its currently observed size. They propose the “no-boundary proposal” combined with a plateau-shaped inflationary potential as a concrete implementation of this idea. This theory aligns with the concept of “swampland conjectures” and also addresses the dark dimension scenario. While the paper is speculative in nature, it highlights the possibility of a smaller universe, emphasizing the importance of testable predictions in theoretical cosmology.
https://telescoper.blog/2023/10/05/the-return-of-a-small-universe/