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Gomis, Jaume

Publications and source records attributed to Gomis, Jaume.

Phases Of Adjoint QCD$_3$ And Dualities

We study 2+1 dimensional gauge theories with a Chern-Simons term and a fermion in the adjoint representation. We apply general considerations of symmetries, anomalies, and renormalization group flows to determine the possible phases of the theory as a function of the gauge group, the Chern-Simons level k k , and the fermion mass. We propose an inherently quantum mechanical phase of adjoint QCD with small enough k k , where the infrared is described by a certain Topological Quantum Field Theory (TQFT). For a special choice of the mass, the theory has {\cal N}=1 supersymmetry. There this TQFT is accompanied by a massless Majorana fermion – a Goldstino signaling spontaneous supersymmetry breaking. Our analysis leads us to conjecture a number of new infrared fermion-fermion dualities involving SU S U , SO S O , and Sp S p gauge theories. It also leads us to suggest a phase diagram of SO/Sp S O / S p gauge theories with a fermion in the traceless symmetric/antisymmetric tensor representation of the gauge group.

Gomis, Jaume↗

Shortening anomalies in supersymmetric theories

We present new anomalies in two-dimensional N = (2, 2) superconformal theories. They obstruct the shortening conditions of chiral and twisted chiral multiplets at coincident points. This implies that marginal couplings cannot be promoted to background superfields in short representations. Therefore, standard results that follow from N = (2, 2) spurion analysis are invalidated. These anomalies appear only if supersymmetry is enhanced beyond N = (2; 2). These anomalies explain why the conformal manifolds of the K 3 and T 4 sigma models are not Kähler and do not factorize into chiral and twisted chiral moduli spaces and why there are no N = (2, 2) gauged linear sigma models that cover these conformal manifolds. We also present these results from the point of view of the Riemann curvature of conformal manifolds.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Anomalies, conformal manifolds, and spheres

The two-point function of exactly marginal operators leads to a universal contribution to the trace anomaly in even dimensions. We study aspects of this trace anomaly, emphasizing its interpretation as a sigma model, whose target space $M$ is the space of conformal field theories (a.k.a. the conformal manifold). When the underlying quantum field theory is supersymmetric, this sigma model has to be appropriately supersymmetrized. As examples, we consider in some detail $N$ = (2; 2) and $N$ = (0; 2) supersymmetric theories in d = 2 and $N$ = 2 supersymmetric theories in d = 4. This reasoning leads to new information about the conformal manifolds of these theories, for example, we show that the manifold is K ahler-Hodge and we further argue that it has vanishing K ahler class. For $N$ = (2; 2) theories in d = 2 and N = 2 theories in d = 4 we also show that the relation between the sphere partition function and the K ahler potential of $M$ follows immediately from the appropriate sigma models that we construct. Ultimately, along the way we find several examples of potential trace anomalies that obey the Wess-Zumino consistency conditions, but can be ruled out by a more detailed analysis.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗