Combining space and time into four dimensions demonstrates invariance under Lorentz transformation.
Space-time being so fundamental an attribute of our universe, there must be numerous analogues. What invariances apply to them, if any?
This is a corollary to the question: https://www.researchgate.net/post/Apart_from_space-time_are_there_any_other_mathematical_models_of_physical_phenomena_using_a_fourth_dimension
And:
Preprint Size, scaling, and invariant ratios