Borsboom, Silvester G.A. and Dupont, José P. (2026) Symmetry Breaking through Superselection by Boundary Conditions. [Preprint]
![[img]](https://philsci-archive.pitt.edu/style/images/fileicons/text.png) |
Text
SB_superselection_boundaries.pdf Download (481kB) |
Abstract
Spontaneous symmetry breaking (SSB) is central to modern physics but is conventionally defined only for infinite systems, raising challenges for its interpretation in finite, real-world setups. This paper argues that the key to resolving this issue lies in the underappreciated role of boundary conditions in quantum systems. Inspired by both the relational approach to symmetries and the physical mechanism behind symmetry breaking, we formulate a relational interpretation of SSB: a finite system exhibits SSB relative to a reference environment which can induce perturbations across the boundary. This eliminates the need for the thermodynamic limit, offering a more physical picture of SSB that emphasizes the observable consequences of the interactions that real-life systems inevitably have with their environment. We show how, in this relational interpretation, SSB for both lattice systems and (gauge) field theories should be understood as subtle, rather than spontaneous, symmetry breaking, still in contrast to explicit symmetry breaking. We also explain how algebraic definitions of SSB for infinite systems relate to the intuitive picture of SSB in finite systems and illustrate how asymptotic boundary conditions push the environment "to infinity". In this way, our relational interpretation of SSB provides a unified conceptual framework applicable to symmetry-breaking in systems of any size.
| Export/Citation: | EndNote | BibTeX | Dublin Core | ASCII/Text Citation (Chicago) | HTML Citation | OpenURL |
| Social Networking: |
| Item Type: | Preprint | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Creators: |
|
|||||||||
| Keywords: | symmetry breaking, superselection, gauge symmetry, boundary conditions, Ising model, quantum reference frames | |||||||||
| Subjects: | Specific Sciences > Physics > Condensed Matter Specific Sciences > Physics > Quantum Field Theory Specific Sciences > Physics > Quantum Mechanics Specific Sciences > Physics > Symmetries/Invariances |
|||||||||
| Depositing User: | Mr. Silvester G.A. Borsboom | |||||||||
| Date Deposited: | 13 Jun 2026 12:46 | |||||||||
| Last Modified: | 13 Jun 2026 12:46 | |||||||||
| Item ID: | 30103 | |||||||||
| Subjects: | Specific Sciences > Physics > Condensed Matter Specific Sciences > Physics > Quantum Field Theory Specific Sciences > Physics > Quantum Mechanics Specific Sciences > Physics > Symmetries/Invariances |
|||||||||
| Date: | 13 June 2026 | |||||||||
| URI: | https://philsci-archive.pitt.edu/id/eprint/30103 |
Monthly Views for the past 3 years
Monthly Downloads for the past 3 years
Plum Analytics
Actions (login required)
 |
View Item |
![[feed]](http://philsci-archive.pitt.edu/style/images/feed-icon-32x32.png){kind=icon}