Many characters in my novel already have access to the hyperuniverse that encloses the physical universe in which we live, so it doesn’t make sense for them to discuss its shape or its size, all because they have seen and measured it, pretty much the same way we see our planet Earth today. Therefore, I expect my readers to understand that Shu was teasing those who had not seen the physical universe from outside. Plus, I allow my characters to get drunk, to lie, to brag, to tease and to say whatever they want, so it becomes confusing for my readers to see what physical reality I conceive in my novel. This is why I am dedicating this small post to clarify a few hypothetical “physical facts”. My physical theory is not designed to be easily and cheaply falsifiable, but rather just consistent enough with our present observation, closer to string theory than to loop quantum gravity in spirit simply because I am just writing a novel, no more and no less. So, please do not take it as a serious scientific theory. Furthermore, I want to keep all “physical facts” simple, clear and natural, like all physical theories should. This way, I make sure I can even entertain 5th-graders who want to enjoy my novel by asking them to picture everything in 3-D analogies.
- The physical universe is a 3-sphere, hence a 3-manifold that expands in a 4-manifold hyperuniverse because the Big Bang explodes in all directions with equal force, which explains why there is no observable center of explosion because it lies outside of the 3-manifold in which we live. The reason why it sounds different from a 4-manifold spacetime that most physicists talk about is that time is not a topological dimension in which we can go back and forth and that time is not cumulative from the initial explosion, either, just as mass is not, which is independent of age anyway. The 4-manifold spacetime is useful for them because they work with 4-vectors and consider the chronology of the universe as a whole, where the entire past coexists with the present time, cumulatively. Unfortunately, I only consider the universe at its present time, as the universe-now instead of its spacetime continuum, just as the planet Earth now is 3-D while its spacetime continuum is 4-D. The beauty of having a 3-sphere as the physical model of the universe is the fact that particles do not leak without special mechanisms while traveling in their 3-manifold.
- The physical universe is either completely opaque or completely transparent for each particle, because we do not observe them traveling through from higher dimensions. Hence, they either don’t get in at all or don’t interact with the known particles confined in the 3-manifold universe. The probability is very high that the 3-sphere is opaque because particles don’t pass through other particles just like that. They hit, and when they hit, they hit hard.
- The dimensionality of the gravitational force is a lot higher than that of the electromagnetic force, which explains why it is relatively weak, why gravitons leak like crazy unlike most other particles and why spacetime acts as a perfect background of quantum mechanics, participating in all theoretical dimensions, subatomic or macroscopic.
- The velocitational field exists, probably linked to the Higgs field, together dictating the relativistic behavior of inertia, independent of the expansion of the universe, a possibility that assumes 3 different types of mass: invariant mass, inertial mass and gravitational mass.
- The relativistic effect is a lot weaker in higher dimensions, obviously, by following the surface area formulae for n-spheres, which probably implies that universal speed limits would be a lot higher in higher dimensions as well, likely as an exponential function of dimensionality. Of course, we assume that the relativistic effect literally disappears at one point, as we do not want to assume that nature has infinitely many physical dimensions. Higher universal speed limits can be approximated by matching the behaviors of acceleration predicted by both the velocitational field and the gravitational field, plus some degree of freedom, without contradicting with our observation in spacetime.
The above assumptions make my novel difficult to falsify for the next few centuries, if not millennia. I hope you like them.