I haven't read the contents of these references.
So, I can't comment on them.
I have merely tracked down what appear to be relevant references on the topic....
possibly what the OP "read somewhere".
Olivier Costa de Beauregard's
"Isomorphisme de la dynamique relativiste des systèmes de points et de la statique classique des systèmes de fils" - Cahiers de physique, 80, avril 1957, pp. 137-148
http://www.costa-de-beauregard.com/fr/wp-content/uploads/2012/09/OCB-1957-10.pdf
Here is the abstract:
Sommaire: On met en evidence l'isomorphisme entre la dynamique relativiste du point et la statique classique du fil (voir tableau de correspondancecorrespondances 1) entre la dynamique relativiste des systèmes de charges electrisees de Wheeler-Feynman [11] et la statique classique des systemes de fils en interaction. Accessoirement, l'on discute de la définition covariante relativiste du barycentre [9, 12] et de l'énoncé relativiste des théorèmes généraux de la dynamique [12] puis de la relation entre l’irréversibilité macroscopique du rayonnement et celle de la thermodynamique.
which Google Translate translatestry to translate as
"Isomorphism of relativistic dynamics of point systems and classical static of wire systems"
Summary: The isomorphism between the relativistic momentum of the point and the classical static of the yarn (see correlation table 1) is revealed between the relativistic dynamics of the Wheeler-Feynman [11] electric charge systems and the classical static of the wires. in interaction. Incidentally, we discuss the relativistic covariant definition of the centroid [9, 12] and the relativistic statement of the general theorems of dynamics [12] and then the relation between the macroscopic irreversibility of radiation and that of thermodynamics.
Summary: The isomorphism between the relativistic momentum of the point and the classical static of the yarn (see correlation table 1) between the relativistic dynamics of Wheeler-Feynman's electrified charge systems [11] and the classical static of the systems is demonstrated. son in interaction. Incidentally, we discuss the relativistic covariant definition of the centroid [9, 12] and the relativistic statement of the general theorems of dynamics [12] and then the relation between the macroscopic irreversibility of radiation and that of thermodynamics.
I found that reference from this article at
https://arxiv.org/abs/1711.03568
Calin Galeriu's
"Relativistic Point Particles and Classical Elastic Strings"
whose abstract reads
We extend the previous work of Olivier Costa de Beauregard regarding the isomorphism between the equation describing the motion of relativistic point particles and the equation describing the static equilibrium of classical elastic strings, by comparing the Lagrangians of these two systems.