S-Matrix Theory - Wikipedia - wikipedia.org  ## Metadata - Author: **wikipedia.org** - Full Title: S-Matrix Theory - Wikipedia - Category: #articles - URL: https://en.wikipedia.org/wiki/Landau_principle ## Highlights - ***S*-matrix theory** was a proposal for replacing local [quantum field theory](https://en.wikipedia.org/wiki/Quantum_field_theory) as the basic principle of elementary [particle physics](https://en.wikipedia.org/wiki/Particle_physics). It avoided the notion of space and time by replacing it with abstract mathematical properties of the [*S*-matrix](https://en.wikipedia.org/wiki/S-matrix). In *S*-matrix theory, the *S*-matrix relates the infinite past to the infinite future in one step, without being decomposable into intermediate steps corresponding to time-slices. This program was very influential in the 1960s, because it was a plausible substitute for [quantum field theory](https://en.wikipedia.org/wiki/Quantum_field_theory), which was plagued with the [zero interaction phenomenon](https://en.wikipedia.org/wiki/Landau_pole) at strong coupling. Applied to the strong interaction, it led to the development of [string theory](https://en.wikipedia.org/wiki/String_theory). *S*-matrix theory was largely abandoned by physicists in the 1970s, as [quantum chromodynamics](https://en.wikipedia.org/wiki/Quantum_chromodynamics) was recognized to solve the problems of strong interactions within the framework of field theory. But in the guise of string theory, *S*-matrix theory is still a popular approach to the problem of quantum gravity. ([View Highlight](https://read.readwise.io/read/01jwaga6b1g4c7h73ekja9rhpq))