Is there a known mathematical foundation to the concept of emergence? I'm researching many topics including emergence and chaos theory, and I cannot for the life of me find strictly mathematical treatments of the idea of emergence. Is there any form or field of mathematics that can predict the emergence of one equation from another, or from a set of equations? A simple analogy would be the "emergence" of a velocity equation by differentiating the position equation, and an acceleration equation from a velocity equation. More aptly, for example, is there any known way in which the Navier-Stokes equation can "emerge" from the equations of Schrödinger, Pauli or Dirac (or even the equations of QCD)? Some relatively "simple" transformation based upon, perhaps, a single parameter (ideally, maybe scale, energy, etc), that can change an equation from one integrative level to an equation from a higher/lower integrative level?
I realize this seems to be a hotly debated topic in some ways, but I cannot seem to find what I am looking for. My intuition for some reason says this may involve, among other ideas, fractional differential equations, Galois theory, fractal geometry, nested matrices, Fourier/Laplace transformations, that kind of thing. Deep down (despite my lack of formal mathematical education), I truly feel there HAS to be a relatively simple way in which equations can be transformed from small-scale dynamics to larger, emergent phenomena. Imagine having a transformation that could transform the Schrödinger equation smoothly through the Pauli equation, then the Dirac equation, on up through the Navier-Stokes equation (finally?) arriving at the Einstein Field Equations, all based upon a few (maybe even a single) parameter(s).
 A: There is no known way of deriving the Navier-Stokes equation from the Bolzmann equations.
There are attempts at putting emergence on a firm mathematical foundation in very wide generality. While the following introduces it only in the context of cellular automata, it generalises well to other domains: 
Robert S. MacKay.Space-time phases, page 387–426. London Mathematical Society Lecture Note Series. Cambridge University Press, 2013.
See also this paper for another method for quantifying emergence using shannon entropy:
ROBIN C. BALL, MARINA DIAKONOVA, and ROBERT S. MACKAY.Quantifying emergence in terms of persistent mutual information.Advancesin Complex Systems, 13(03):327–338, 2010.
A: There is no method (known) in full generality.  The does exist a huge amount of literature, mainly in physics, on deriving the equations of continuous or "large" systems as a statistical mechanics limit of N-particle systems.
Emergence usually means something broader than reduction of macroscopic equations to microscopic ones.  The idea more is different is that phenomena and quantities that describe a large system can be qualitatively different than those useful for the description of its microscopic building blocks, and knowing the lower level completely is not always sufficient to understand the higher level.
A: I am reading https://arxiv.org/abs/1904.03424 "Emergence via non-existence of averages" and it mentions Berger's emergence and evelops a pointwise emergence and this article contains statement ([10] is reference to Berger article):

we note that “emergence” is one of the most important concepts in
complexity science [34], but had no rigorous formulation before [10]
appeared

that suggests that such mathematical theory of emergence has been made at last.
I will expand my answer a bit later after reading the article.
