Contents

# Contents

## Idea

In the plain minimally supersymmetric standard model (MSSM), baryon/lepton number would not need to be preserved. Since however experimental observation indicates that these quantum observables are preserved to high accuracy, a common ad hoc solution in bottom-up model-building is to impose a certain Z/2-action on the MSSM as a global symmetry, called R-parity, which does enforce baryon/lepton number conservation.

From a top-down model building-perspective there is the rough idea that R-parity may be thought of as a discrete remnant of R-symmetry (e.g. Chamseddine-Dreiner 96, p. 2, Frugiuele-Gregoire 11)

There remain speculations that even if MSSM-like models are realistic, R-parity might in fact be violated in nature after all, such as as possibly indicated by the apparent flavour anomalies (Wang-Yang-Yuan 19).

## References

The original articles are

Discussion of possible relation to R-symmetry:

• Ali Chamseddine, Herbi Dreiner, Anomaly-Free Gauged R-Symmetry in Local Supersymmetry, Nucl.Phys. B458 (1996) 65-89 (arXiv:hep-ph/9504337)

• Claudia Frugiuele, Thomas Gregoire, Making the Sneutrino a Higgs with a $U(1)_R$ Lepton Number, PhysRev D.85.015016 (arXiv:1107.4634)

• Saul Ramos-Sanchez, Section 5.4 of Towards Low Energy Physics from the Heterotic String, Fortsch. Phys. 10:907-1036, 2009 (arXiv:0812.3560)

Suggestion that the MSSM with R-parity violation could explain the flavour anomalies:

• Dong-Yang Wang, Ya-Dong Yang, Xing-Bo Yuan, $b \to c \tau \bar \nu$ decays in supersymmetry with R-parity violation (arXiv:1905.08784)

Last revised on July 28, 2019 at 17:33:01. See the history of this page for a list of all contributions to it.