Supersymmetric Proximity

TL;DR

The paper explores a perturbative proximity between supersymmetric and non-supersymmetric theories, using deformations of super-Yang-Mills to gain insights into non-supersymmetric gluodynamics and related models.

Contribution

It introduces a method to relate supersymmetric theories to non-supersymmetric ones via deformations, providing new insights into their beta functions and dynamics.

Findings

Exact results in deformed theories reveal beta function splitting.

Proximity between pure gluodynamics and adjQCD with two flavors.

Application of ideas to 2D CP(1) sigma model with supersymmetry.

Abstract

I argue that a certain perturbative proximity exists between some supersymmetric and non-supersymmetric theories (namely, pure Yang-Mills and adjoint QCD with two flavors, adjQCD$_{N_f=2}$). I start with ${\mathcal N}=2$ super-Yang-Mills theory built of two ${\mathcal N}=1$ superfields: vector and chiral. In ${\mathcal N}=1$ language the latter presents matter in the adjoint representation of SU$(N). $ Then I convert the matter superfield into a "{\em phantom}" one (in analogy with ghosts), breaking ${\mathcal N}=2$ down to ${\mathcal N}=1$. The global SU(2) acting between two gluinos in the original theory becomes graded. Exact results in thus deformed theory allows one to obtain insights in certain aspects of non-supersymmetric gluodynamics. In particular, it becomes clear how the splitting of the $\beta$ function coefficients in pure gluodynamics, $\beta_1 =(4 -\frac 13 )N$ and $\beta_2= (6-\frac 13)N^2$, occurs. Here the first terms in the braces (4 and 6, always integers) are geometry-related while the second terms ($-\frac 13$ in both cases) are {\it bona fide} quantum effects. In the same sense adjQCD$_{N_f=2}$ is close to ${\mathcal N}=2$ SYM. Thus, I establish a certain proximity between pure gluodynamics and adjQCD$_{N_f=2}$ with supersymmetric theories. (Of course, in both cases we loose all features related to flat directions and Higgs/Coulomb branches in ${\mathcal N}=2$.) As a warmup exercise I use this idea in 2D CP(1) sigma model with ${\mathcal N}=(2,2)$ supersymmetry, through the minimal heterotic ${\mathcal N}=(0,2) \to$ bosonic CP(1).