I was puzzled when I read "Precise measurements find a crack in universal physics by Ingrid Fadelli" (Phys.org, Jan. 15, 2020). The article has some vague statements in the opening paragraphs about "universal physics":
The concept of universal physics is intriguing, as it enables researchers to relate physical phenomena in a variety of systems, irrespective of their varying characteristics and complexities. Ultracold atomic systems are often perceived as ideal platforms for exploring universal physics, owing to the precise control of experimental parameters (such as the interaction strength, temperature, density, quantum states, dimensionality, and the trapping potential) that might be harder to tune in more conventional systems. In fact, ultracold atomic systems have been used to better understand a myriad of complex physical behavior, including those topics in cosmology, particle, nuclear, molecular physics, and most notably, in condensed matter physics, where the complexities of many-body quantum phenomena are more difficult to investigate using more traditional approaches.
Understanding the applicability and the robustness of universal physics is thus of great interest. Researchers at the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder have carried out a study, recently featured in Physical Review Letters, aimed at testing the limits to universality in an ultracold system.
A Web search for the (seemingly redundant) phrase "universal physics" turns up a mix of things. Some stuff appears to be unrelated. Some stuff that turned up was some pseudoscience nonsense rejecting relativity and quantum mechanics in favor of continued belief in Newtonian physics. An occasional result did appear to be related to the Efimov trimer state stuff described in the PRL paper the article discusses.
("Precision Test of the Limits to Universality in Few-Body Physics" Roman Chapurin, Xin Xie, Michael J. Van de Graaff, Jared S. Popowski, José P. D’Incao, Paul S. Julienne, Jun Ye, and Eric A. Cornell Phys. Rev. Lett. 123, 233402 – Published 2 December 2019 -- arXiv preprint here, synopsis here.)
The PRL paper the article is about does not itself include the term "universal physics". However, one of the co-authors of the journal paper is quoted in the phys.org article as saying "Universal behavior is independent of the microscopic details. Understanding the limitations of universal phenomenon is of great interest." And the paper does discuss things like "van der Waals universality".
So what is a decent definition of "universal physics" in this context? (If possible, in terms that might make at least a little sense to a layman.)