Fiol Núñez, BartomeuQuera Bofarull, Arnau2015-10-222015-10-222015-06https://hdl.handle.net/2445/67410Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Any: 2015, Tutor: Tomeu FiolWe present the Lee-Yang theory that links the study of phase transitions to the localization of zeros in the complex fugacity plane. We prove the Lee-Yang theorem using Asano's contraction method and we apply it for the one and two dimensional Ising model. We also show that the Lee-Yang formalism can shed some light on the di cult task of counting the number of ground states in supersymmetric theories.5 p.application/pdfengcc-by-nc-nd (c) Quera Bofarull, 2015http://creativecommons.org/licenses/by-nc-nd/3.0/es/Mecànica estadísticaTransformacions de fase (Física estadística)Treballs de fi de grauStatistical mechanicsPhase transformations (Statistical physics)Bachelor's thesesinfo:eu-repo/semantics/bachelorThesisinfo:eu-repo/semantics/openAccess