Stefano Piemonte

The light bound states of supersymmetric SU(2) Yang-Mills theory

A bstractSupersymmetry provides a well-established theoretical framework for extensions of the standard model of particle physics and the general understanding of quantum field theories. We summarise here our investigations of N=1

Phase structure of the \( \mathcal{N}=1 \) supersymmetric Yang-Mills theory at finite temperature

\mathcal{N}=1

Perturbative calculation of the clover term for Wilson fermions in any representation of the gauge group SU(N)

supersymmetric Yang-Mills theory with SU(2) gauge symmetry using the non-perturbative first-principles method of numerical lattice simulations. The strong interactions of gluons and their superpartners, the gluinos, lead to confinement, and a spectrum of bound states including glueballs, mesons, and gluino-glueballs emerges at low energies. For unbroken supersymmetry these particles have to be arranged in supermultiplets of equal masses. In lattice simulations supersymmetry can only be recovered in the continuum limit since it is explicitly broken by the discretisation. We present the first continuum extrapolation of the mass spectrum of supersymmetric Yang-Mills theory. The results are consistent with the formation of super-multiplets and the absence of non-perturbative sources of supersymmetry breaking. Our investigations also indicate that numerical lattice simulations can be applied to non-trivial supersymmetric theories.

Simulations of N=1 supersymmetric Yang-Mills theory with three colours

A bstractFermion boundary conditions play a relevant role in revealing the confinement mechanism of N=1

The light bound states of \( \mathcal{N}=1 \) supersymmetric SU(3) Yang-Mills theory on the lattice

\mathcal{N}=1

Ward identities in N = 1 supersymmetric SU(3) Yang-Mills theory on the lattice

supersymmetric Yang-Mills theory with one compactified space-time dimension. A deconfinement phase transition occurs for a sufficiently small compactification radius, equivalent to a high temperature in the thermal theory where antiperiodic fermion boundary conditions are applied. Periodic fermion boundary conditions, on the other hand, are related to the Witten index and confinement is expected to persist independently of the length of the compactified dimension. We study this aspect with lattice Monte Carlo simulations for different values of the fermion mass parameter that breaks supersymmetry softly. We find a deconfined region that shrinks when the fermion mass is lowered. Deconfinement takes place between two confined regions at large and small compactification radii, that would correspond to low and high temperatures in the thermal theory. At the smallest fermion masses we find no indication of a deconfinement transition. These results are a first signal for the predicted continuity in the compactification of supersymmetric Yang-Mills theory.