What does that mean and where does the idea come from?
I recently (Feb 2024) came across the mathematical conjectures of Marco Pereira which he calls Lightspeed Expanding Hyperspherical Universe Topology or LEHU for short. As I am not a mathematician I am not able to critique his extensive (no pun intended) examinations and adaptations/adjustments of the formulae of General and Special Relativity. I do not immediately dismiss his ideas is because
- they seem to be expressed in very rigorously constructed mathematics, and
- he applies his principals to several diverse sets of astronomical data created by numerous projects run by official government and other research orgainisations world wide.
I am disappointed to see that nobody in the mainstream astronomical/astrophysical communities has taken the time to make a principled review of his underlying hypothesis or its mathematical underpinnings. It may well be that his overly assertive and/or aggressive language has put potential reviewers off. (I intend to ask him about this.)
Meanwhile, his basic thesis is that our universe is four dimensional but the fourth dimension is not “time” as such but a spacial dimension which is expanding at the speed of light. To be clear: this dimension is definitely orthogonal (at right angles) to our “normal” 3D directions (x, y, and z) and commenced its expansion at what is called the Big Bang (BB).
In looking at his diagrammatic representations I understand that his thesis allows changes over time to the space-time distance between two separated points in space to be represented as what happens to locations on the circumference of a circle which is expanding. The difference in radius of the two circles denoting the start and end of the time period is proportionate to how far a photon of light would have travelled in that time. But note that this is a calculational tool of the thesis, and that actual distances will change based on (more or less ) Euclidian geometry and the extent to which this is affected by the expansion of the hypershpere.
From this fundamentally different description of space-time Marco Pereira deduces that many of the currently accepted mathematical descriptions used by physics need to be modified in certain ways and that, furthermore, certain features of our universe, such as gravity, are epoch dependent, ie have really changed during the evolution of our universe so far.
I cannot say more about that, and hopefully I have not misrepresented his thesis with even that short description.
Marco Pereira has placed much of his descriptions and explanations on Quora:
https://hypergeometricaluniverse.quora.com
Why this interests me: what it might mean for MOPECCA
What I like about Marco Pereira’s thesis is how it removes “time” as an ontological thing and lets it be a method if you like, which we construct and use as a means for describing changes amongst things which permanently exist in their own right. That is how the MOPECCA construes time.
Another thing is that, even if Marco P’s mathematical schema turns out to be the Earth shattering breakthrough that modern physics and astronomy both need, it will still be true that mathematics is not ontology. However the ontological implications of this idea are that it very likely reconfigures the constraints around MOPECCA and possibly allows for an explanation of anti-electrons which were not falling easily out of constrains made of 3D + “time”. I am ‘working’ on that now in my spare moments.
Optimistic realism 