2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/184328We study an exactly marginal deformation of N=4 SUSY Yang-Mills with gauge group U(N) using field theory and string theory methods. The classical theory has a Higgs branch for rational values of the deformation parameter. We argue that the quantum theory also has an S-dual confining branch which cannot be seen classically. The low-energy effective theory on these branches is a six-dimensional non-commutative gauge theory with sixteen supercharges. Confinement of magnetic and electric charges, on the Higgs and confining branches respectively, occurs due to the formation of BPS-saturated strings in the low energy theory. The results also suggest a new way of deconstructing Little String Theory as a large-N limit of a confining gauge theory in four dimensions.LaTeX file, 59 pages, no figures. Minor improvements, references addedHigh Energy Physics - TheoryS-Duality, Deconstruction and Confinement for a Marginal Deformation of N=4 SUSY Yang-Millstext