Could each Calabi-Yau space describe a different set of laws in each of those universes?
Yes, each isolated universe can be modeled by a different Calabi-Yau space. But some of my colleagues have also studied a beautiful concept called mirror symmetry, in which each space has a mirror image with the same quantum field theory and the same physics. How many Calabi-Yau spaces are there? Using a computer program, Philip Candelas at the University of Texas at Austin found up to 10,000 Calabi-Yau spaces, with almost half of them mirror partners of each other. Each member of a pair is topologically distinct but still conforms to the other algebraically and gives rise to the same forces, the same particles, the same rules. The resulting geometric structure can be used to determine physical quantities associated with each space, like particle mass. String theory is often described as a mathematically elegant way to explain all of physics. But how can we know that it describes the real universe? We cannot know for sure, but the mathematics inspired by string theory solves some old,
