3 research outputs found
Gonihedric Ising Actions
We discuss a generalized Ising action containing nearest neighbour, next to
nearest neighbour and plaquette terms that has been suggested as a potential
string worldsheet discretization on cubic lattices by Savvidy and Wegner. This
displays both first and second order transitions depending on the value of a
``self-intersection'' coupling as well as possessing a novel semi-global
symmetry.Comment: Latex + 2 postscript figures. Poster session contribution to
"Lattice96" conference, Washington University, StLoui
Gonihedric 3D Ising Actions
We investigate a generalized Ising action containing nearest neighbour, next
to nearest neighbour and plaquette terms that has been suggested as a potential
string worldsheet discretization on cubic lattices by Savvidy and Wegner. We
use both mean field techniques and Monte-Carlo simulations to sketch out the
phase diagram.
The Gonihedric (Savvidy-Wegner) model has a symmetry that allows any plane of
spins to be flipped with zero energy cost, which gives a highly degenerate
vacuum state. We choose boundary conditions in the simulations that eliminate
this degeneracy and allow the definition of a simple ferromagnetic order
parameter. This in turn allows us to extract the magnetic critical exponents of
the system.Comment: Latex plus 6 postscript figures bundled together with uufiles. The
paper has been completely revised: a judicious choice of boundary conditions
now allows the extraction of magnetic critical exponents. All the exponents,
and even the critical temperature, appear close to those of the standard
two-dimensional Ising mode