arXiv subjects

Stam Nicolis

Publications and source records attributed to Stam Nicolis.

39 records · Page 3Linked to original sources

arXiv2010

Second Order Phase Transition in Anisotropic Lattice Gauge Theories with Extra Dimensions

Field theories with extra dimensions live in a limbo. While their classical solutions have been the subject of considerable study, their quantum aspects are difficult to control. A special class of such theories are anisotropic gauge theories. The anisotropy was originally introduced to localize chiral fermions. Their continuum limit is of practical interest and it will be shown that the anisotropy of the gauge couplings plays a crucial role in opening the phase diagram of the theory to a new phase, that is separated from the others by a second order phase transition. The mechanism behind this is generic for a certain class of models, that can be studied with lattice techniques. This leads to new perspectives for the study of quantum effects of extra dimensions.

hep-lat↗

arXiv2010

Anomaly cancellation for anisotropic lattice fields with extra dimensions

The current flow from the bulk is due to the anomaly on the brane-but the absence of current flow is not, necessarily, due to anomaly cancellation, but to the absence of the chiral zero modes themselves, due to the existence of the layered phase. This can be understood in terms of the difference between the Chern-Simons terms in three and five dimensions. Thus the anomaly cancellation in four dimensions, which is essential for shielding the boundary from quantum effects within the bulk, makes sense only along the transition line between the layered and the Coulomb phase, which, in turn, requires the presence of a compact U(1) factor for the gauge group.

hep-lat↗

arXiv1994

Critical Properties of Stochastic Cellular Automata}

We study the effect of mixing two rules on the dynamics of one-dimensional cellular automata by large scale numerical simulations. We calculate the decay of the magnetization for the Domany-Kinzel automaton (XOR/AND mixing) to its equilibrium value in the three phases. This requires system sizes in excess of 1 million sites. We also find severe finite size effects near the new critical points recently proposed on the basis of transfer matrix arguments.

cond-mat↗