One of the early concerns in quantum field theory was causality – can one ensure that measurements at spacelike separation do not interfere? General issues of this type were important in the days when little was understood about the underlying dynamics of particle interactions; the hope was to place constraints on the types of allowed dynamics and interactions on the basis of cherished tenets o...

We investigate the class of physical theories with the same local structure as quantum theory but potentially different global structure. It has previously been shown that any bipartite correlations generated by such a theory can be simulated in quantum theory but that this does not hold for tripartite correlations. Here we explore whether imposing an additional constraint on this space of theo...

This paper introduces a family of error-correcting codes called zigzag codes. A zigzag code is described by a highly structured zigzag graph. Due to the structural properties of the graph, very low-complexity soft-in/soft-out decoding rules can be implemented. We present a decoding rule, based on the Max-Log-APP (MLA) formulation, which requires a total of only 20 addition-equivalent operations...

Edge magnetism in zigzag transition metal dichalcogenide nanoribbons is studied using a three-band tight-binding model with local electron-electron interactions. Both mean field theory and the unbiased, numerically exact determinant quantum Monte Carlo method are applied. Depending on edge filling, predicts different phases: gapped spin dimer antiferromagnetic phases appear for two specific fil...

A vortex line passes through as many pinning centers as possible on its way from one extremety of the superconductor to the other at the expense of increasing its self-energy. In the framework of the Ginzburg-Landau theory we study the relative growth in length, with respect to the straight line, of a vortex near a zigzag of defects. The defects are insulating pinning spheres that form a three-...

The feasibility of creating atomic wires on vicinal silicon surfaces via pseudomorphic step-edge decoration has been analyzed for the case of Ga on Si(112). Scanning tunneling microscopy and density functional theory calculations indicate the formation of Ga zigzag chains intersected by quasiperiodic vacancy lines or "misfit dislocations." This structure strikes a balance between the system's d...

The stability of small fractal graphene models with two different symmetries and Fe atoms at their mixed edges is addressed by density functional theory (DFT) calculations. Four kinds edge configurations atom localizations are determined depending on the model. have configuration, zig-zag “intra-zig-zag” in symmetrical structures armchair type architectures rotational symmetry. symmetry exhibit...