Biomedical subjects

Robert Shrock

Publications and source records attributed to Robert Shrock.

3 recordsLinked to original sources

PubMed2004

Exact results for average cluster numbers in bond percolation on lattice strips.

We present exact calculations of the average number of connected clusters per site, , as a function of bond occupation probability p, for the bond percolation problem on infinite-length strips of finite width Ly, of the square, triangular, honeycomb, and kagomé lattices Lambda with various boundary conditions. These are used to study the approach of , for a given p and Lambda, to its value on the two-dimensional lattice as the strip width increases. We investigate the singularities of in the complex p plane and their influence on the radii of convergence of the Taylor series expansions of about p=0 and p=1 .

Journal Article↗

PubMed2003

Dynamical symmetry breaking of extended gauge symmetries.

We construct asymptotically free gauge theories exhibiting dynamical breaking of the left-right gauge group G(LR)=SU(3)(c) x SU(2)(L) x SU(2)(R) x U(1)(B-L), and its extension to the Pati-Salam gauge group G(422)=SU(4)(PS) x SU(2)(L) x SU(2)(R). The models incorporate technicolor for electroweak breaking, and extended technicolor for the breaking of G(LR) and G422 and the generation of fermion masses. They include a seesaw mechanism for neutrino masses, without a grand unified theory (GUT) scale. These models explain why G(LR) and G422 break to SU(3)(c) x SU(2)(L) x U(1)(Y), and why this takes place at a scale (approximately 10(3) TeV) large compared to the electroweak scale, but much smaller than a GUT scale.

Journal Article↗

PubMed2002

n-n* oscillations in models with large extra dimensions.

We analyze n-n* oscillations in generic models with large extra dimensions in which standard-model fields propagate and fermion wave functions have strong localization. We find that in these models n-n* oscillations might occur at levels not too far below the current limit.

Journal Article↗