What the study found
The study finds that a 1+1-dimensional SU(N) gauge theory with an adjoint Majorana fermion, called adjoint QCD2, exhibits supersymmetry when the fermion mass is set to a specific value. It also identifies related models in which a supersymmetric massive sector coexists with a non-supersymmetric conformal field theory (CFT, a theory describing scale-invariant behavior).
Why the authors say this matters
The authors say their construction gives a deeper insight into how supersymmetry works in adjoint QCD2. They also conclude that the same framework can be generalized to other gauge theories, and in some cases both the massive and gapless sectors are supersymmetric.
What the researchers tested
The researchers constructed a gauge-invariant, Lorentz-covariant supercurrent, which is a conserved current associated with supersymmetry. They extended this construction to a class of gauge theories that include an adjoint Majorana fermion of appropriate mass together with additional massless fermions, and they noted that SU(N) can be replaced by a more general gauge group.
What worked and what didn't
The supercurrent construction worked for adjoint QCD2, and its conservation depended crucially on a quantum anomaly. In the generalized models, the authors report a supersymmetric massive sector together with a non-supersymmetric CFT sector in general, but they also identify cases in which both sectors are supersymmetric; one example is SU(N) gauge theory with three adjoint Majorana fermions, two massless and one with a specific mass.
What to keep in mind
The abstract does not describe experimental data or numerical tests, so the summary is limited to the theory construction and stated examples. It also does not provide detailed limitations beyond noting that the generalized models are not always fully supersymmetric.
Key points
- Adjoint QCD2 shows supersymmetry at a specific adjoint fermion mass.
- The authors construct a gauge-invariant, Lorentz-covariant supercurrent.
- The supercurrent conservation relies on a quantum anomaly.
- Generalized gauge theories can have a supersymmetric massive sector and a non-supersymmetric CFT sector.
- A fully supersymmetric gapless example is SU(N) gauge theory with three adjoint Majorana fermions.
Disclosure
- Research title:
- Adjoint QCD2 can exhibit supersymmetry at specific fermion masses
- Authors:
- Igor R. Klebanov, Silviu S. Pufu, Benjamin T. Søgaard, Edward Witten
- Institutions:
- Princeton University, Princeton University, Princeton University
- Publication date:
- 2026-04-27
- OpenAlex record:
- View
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