In Tibetan Buddhism, the Kalacakra Tantra describes three different worlds – external, internal, and secret – and their connection to one another. The external is the universe, including the solar system, Milky Way, etc.; the internal is the physiology of the human body; the secret is the mind. It is explained that our spiritual world is a universe; the structure of our body is a universe; the universe outside is also a universe. All three are closely connected. To a certain degree, they affect one another.
~Depicted from ARE YOU READY FOR HAPPINESS -Suffering is just a Paper Tiger