The theoretical study and recent experimental realization of long-range interacting systems unveiled new striking phenomena, overcoming usual paradigms of the short-range physics.
In my talk I exploit a simple long-range generalization of the common Ising model in a transverse field to illustrate some of these phenomena, as:
i) the occurrence of nonlocal effects, like the lack of a maximum propagation velocity for a signal or the algebraic decay for correlation functions in gapped regimes,
ii) the breakdown of conformal symmetry for continuous critical points,
iii) the appearance of continuous phase transitions with nonvanishing mass gap,
leading to new phases and new edge excitations,
iv) the necessity to consider non standard decoupling hierachies in the RG approaches.
In spite of the simplicity of the assumed toy-model, the described properties are inferred to be general for long-range systems.
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Luca Lepori
Padova University