Publications

We explore new infrared dualities in (2+1)-dimensional quantum field theories involving Majorana fermions. Building on the recently proposed operator-deformation approach to bosonization dualities, we incorporate the bosonization of neutral fermions into the established web of Dirac dualities. Starting from the decomposition of a Dirac fermion into two Majorana components, we derive a hierarchy of dual bosonic descriptions based on orthogonal Chern-Simons-matter theories. This construction leads to novel boson-boson dualities, including an explicit correspondence between an SO(N) theory with two real scalars and a U(1) theory with one complex scalar, and their generalizations to arbitrary numbers of Majorana flavours. We analyze boundary conditions preserving chirality and demonstrate their role in matching gravitational anomalies and chiral central charges. Additional deformations yield orthogonal analogues of Ising-Gross-Neveu and pairing transitions. The resulting framework provides a unified Majorana-based extension of the three-dimensional duality web and clarifies the infrared structure of non-Abelian bosonization.

We carry out a systematic study of the effective bosonic string describing confining flux tubes in SU(N) Yang-Mills theories in three spacetime dimensions. While their low-energy properties are known to be universal and are described well by the Nambu-Gotō action, a non-trivial dependence on the gauge group is encoded in a series of undetermined subleading corrections in an expansion around the limit of an arbitrarily long string. We quantify the first two of these corrections by means of high-precision Monte Carlo simulations of Polyakov-loop correlators in the lattice regularization. We compare novel lattice simulations for theories with N=3 and 6 color charges, and report an improved estimate for N=2, discussing the approach to the large-N limit. Our results are compatible with analytical bounds derived from the S-matrix bootstrap approach. We also present a new test of the Svetitsky-Yaffe conjecture for the SU(3) theory in three dimensions, finding excellent agreement between lattice results and conformal-perturbation predictions for the three-state Potts model in two dimensions.

We study the effective string describing the infrared dynamics of SU(2) Yang-Mills theory in three dimensions. By combining high-precision lattice simulations of Polyakov-loop correlators at temperatures near deconfinement with analytical constraints from renormalization-group arguments, exact integrability of the two-dimensional Ising model, conformal perturbation theory and Lorentz invariance, we derive tight quantitative bounds on corrections to the effective string action beyond the Nambu-Goto approximation. These corrections are compatible with predictions from a bootstrap analysis of the effective string theory, but their value does not allow the Axionic String Ansatz to be established for this model.

Near the deconfinement transition, the interquark potential can be predicted precisely using effective string theory. If the transition is continuous, effective-string results can be combined with conformal perturbation theory to detect corrections beyond the Nambu-Goto approximation. For SU(2) gauge theory in (2+1) dimensions we use high-precision simulations to show that the Polyakov-loop correlator is described by the spin-spin correlator of the two-dimensional Ising model from the critical point down to temperatures around 0.8 Tc. Exact integrability extends the comparison beyond the conformal-perturbation regime, allowing us to quantify the first effective-string correction beyond Nambu-Goto and show compatibility with bootstrap bounds.

We consider the three-dimensional Ising model perturbed by the energy operator coupled to a non-uniform harmonic potential acting as a trap, and show that the system satisfies trap-size scaling. We compute spin-spin, energy-energy and spin-energy correlators near the critical point using conformal perturbation theory. Combining these results with Monte Carlo simulations, we estimate several OPE coefficients and find good agreement with independently obtained values.

We study the accuracy and predictive power of conformal perturbation theory by comparing with lattice results near the finite-temperature deconfinement transition of SU(2) Yang-Mills theory, assuming its infrared properties near criticality are described by the Ising model. The comparison shows that conformal perturbation theory yields quantitatively accurate predictions over a broad temperature range. We discuss implications for the critical point in another strongly coupled, non-supersymmetric non-Abelian gauge theory: the critical endpoint in the QCD phase diagram at finite temperature and quark chemical potential.

Statistical systems near a classical critical point can be characterized through correlation functions, but computing physical quantities away from criticality requires information about the critical conformal theory. Recent progress in conformal-field-theory data, especially from the conformal bootstrap, motivates extending this information off criticality. We review and clarify how critical correlators can be used to calculate their behavior away from the critical point in a controlled way, requiring only scale invariance at criticality. The method is illustrated for different perturbations of the two-dimensional Ising model.