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20212025
most citedQuantum Statistical Mechanics via Boundary Conditions. A Groupoid Approach to Quantum Spin Systems

2 citations · 3 across the 6 of their papers we have counts for

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6 papers

math-ph2025

Cluster Expansion and Decay of Correlations for Multidimensional Long-Range Ising Models

Lucas Affonso, Rodrigo Bissacot, João Maia +2

We develop the cluster expansion for the multidimensional multiscaled contours defined by three of us. These contours are suitable for long-range Ising models with interaction $J_{…

math-ph2024

Phase Transitions on 1d Long-Range Ising Models with Decaying Fields: A Direct Proof via Contours

Lucas Affonso, Rodrigo Bissacot, Henrique Corsini +1

Following seminal work by J. Fröhlich and T. Spencer on the critical exponent , we give a proof via contours of phase transition in the one-dimensional long-range ferromagneti…

math-ph2024

Phase Transition in Long-Range state Models via Contours. Clock and Potts Models with Fields

Lucas Affonso, Rodrigo Bissacot, Gilberto Faria +1

Using the group structure of the state space of state models, a new definition of contour for long-range spin-systems in (), and a multidimensional version of F…

math-ph2023

Phase Transitions in Multidimensional Long-Range Random Field Ising Models

Lucas Affonso, Rodrigo Bissacot, João Maia

We extend a recent argument by Ding and Zhuang from nearest-neighbor to long-range interactions and prove the phase transition in a class of ferromagnetic random field Ising models…

math-ph2022★ 2 cited

Quantum Statistical Mechanics via Boundary Conditions. A Groupoid Approach to Quantum Spin Systems

Lucas Affonso, Rodrigo Bissacot, Marcelo Laca

We use a groupoid model for the spin algebra to introduce boundary conditions on quantum spin systems via a Poisson point process representation. We can describe KMS states of quan…

math-ph2021★ 1 cited

Long-Range Ising Models: Contours, Phase Transitions and Decaying Fields

Lucas Affonso, Rodrigo Bissacot, Eric O. Endo +1

Inspired by Fröhlich-Spencer and subsequent authors who introduced the notion of contour for long-range systems, we provide a definition of contour and a direct proof for the phase…