Dimensions

In fiction a Dimension (also known as a parallel or alternate universe) is a realm that is larger than a planet and often runs on alien physics from the mainstream universe, beings from such Dimensions are thus often extremely powerful and don't have to obey the laws of nature as we know them.

The concept can also go further than simple metaphysics and encompass spiritual realms and afterlives, which have been central in many mythologies and religions since prehistory.