Nambu monopoles in lattice Electroweak theory  Journal of
Physics G Nuclear and Particle Physics (Impact Factor: 5.33).
07/2007; DOI:10.1088/0954-3899/36/7/075008 Source: arXiv
ABSTRACT We considered the lattice electroweak theory at
realistic values of $\alpha$ and $\theta_W$ and for large values
of the Higgs mass. We investigated numerically the properties of
topological objects that are identified with quantum Nambu
monopoles. We have found that the action density near the Nambu
monopole worldlines exceeds the density averaged over the
lattice in the physical region of the phase diagram. Moreover,
their percolation probability is found to be an order parameter
for the transition between the symmetric and the broken phases.
Therefore, these monopoles indeed appear as real physical
objects. However, we have found that their density on the
lattice increases with increasing ultraviolet cutoff. Thus we
conclude, that the conventional lattice electroweak theory is
not able to predict the density of Nambu monopo