Vertex operatorの"vertex" の由来を調べていた
はっきりしなかったが
Regge theory(1960年代)→"Triple Pomeron Vertex"(Ramamurti Rajaraman)(1970年代)→string theory(1970年代)
という流れで、だれかが、"Vertex operator（algebra）"を命名したようだ
"vertex" の元々の意味も判然としないが、レッジェ・ポールあるいはレッジェ極（特異点）と関連しているのだろう
取りあえず、調べたところまで貼る

(参考)
https://handwiki.org/wiki/Physics:History_of_string_theory
Physics:History of string theory
Contents
1 1943?1959: S-matrix theory
2 1959?1968: Regge theory and bootstrap models
3 1968?1974: Dual resonance model
4 1974?1984: Bosonic string theory and superstring theory
5 1984?1994: First superstring revolution
6 1994?2003: Second superstring revolution
7 2003?present

https://en.wikipedia.org/wiki/Regge_theory
Regge theory
In quantum physics, Regge theory (/?r?d?e?/) is the study of the analytic properties of scattering as a function of angular momentum, where the angular momentum is not restricted to be an integer multiple of ? but is allowed to take any complex value. The nonrelativistic theory was developed by Tullio Regge in 1959.[1]

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