In 1988 I got interested in theoretical physics and read up on the pop sources, assisted by my brother who was going for his doctorate in the field. I was intrigued by the mystery of the missing element needed for a grand unified theory, and felt that it was supplied by P.D. Ouspensky in his book A New Model of the Universe. I applied his theory of a six-dimensional cosmos to the speculations springing from quantum and relativity physics, and came up with my own model: The Cosmic Apple. At that link is the complete text & graphics, newly restored to my website.
The pivotal notion is strikingly simple, if you can wrap your head around it: time does not flow just in a straight line, but sideways as well. If the length of time is the fourth dimension of the continuum, then the width of time is a literal fifth dimension in a geometrical sense. The abstraction is fleshed out with the idea that this dimension is comprised of an infinite series of parallel worlds, and that the ones closest to our own are populated by ourselves, leading alternative lives. Each “alternity” is a little bit different from life in the universe next door, a little better or a little worse. Is it possible to hop from one reality to another intentionally? I’ve explored this idea in fictional writings: The Wedding of Star and Shadow and Christführer.
If the length and width of time added to the three dimensions of space makes a five-dimensional continuum, then the breadth or depth of time, equivalent to the third dimension of a physical solid, creates a six-dimensional cosmos modeled by our apple. Feel free to take a bite!