Are there Other Universes?

This is one of the more controversial arguments out there. The theory is that there are an infinite number of universes, each which is governed by its own set of laws and physics. Many scientists dismiss this argument as nothing more than speculation, as there is no evidence or mathematical law that allows for the existence of other universes. However, believers in this theory have argued that there are none that disprove it either. This is one mystery which can only be solved if we were able to travel there, however, with the expansion of the universe, it is unlikely humanity will ever find the answer.