Superconnections: an Interpretation of the Standard Model

The mathematical framework of superbundles suggests that one considers the Higgs field as a natural constituent of a superconnection. I propose to take as superbundle the exterior algebra obtained from a Hermitian vector bundle of rank 5 for the Standard Model.Comment: 10 pages, LaTeX2e, AMS fonts. To appear in Electr.J.Diff. E

Superconnections and the Higgs Field

Within the mathematical framework of Quillen, one interprets the Higgs field as part of the superconnection on a superbundle. We propose to take as superbundle the exterior algebra obtained from a Hermitian bundle with structure group U(n). Spontaneous symmetry breaking appears as a consequence of a non-vanishing scalar curvature. The U(1) Higgs model reformulates the Ginzburg-Landau theory, while the U(2) model relates to the electroweak theory with the relation $g^2=3g4^2$ for the gauge coupling constants, the formula $\sin^2\theta=1/4$ for the Weinberg angle, and the ratio $m_W^2 : m_Z^2 : m_H^2 = 3 : 4 : 12$ for the masses (squared) of the W, Z, and Higgs boson (at tree level).Comment: 21 pages, Latex, references added, minor change of conten

Effective Actions for the SU(2) Confinement-Deconfinement Phase Transition

We compare different Polyakov loop actions yielding effective descriptions of finite-temperature SU(2) Yang-Mills theory on the lattice. The actions are motivated by a simultaneous strong-coupling and character expansion obeying center symmetry and include both Ising and Ginzburg-Landau type models. To keep things simple we limit ourselves to nearest-neighbor interactions. Some truncations involving the most relevant characters are studied within a novel mean-field approximation. Using inverse Monte-Carlo techniques based on exact geometrical Schwinger-Dyson equations we determine the effective couplings of the Polyakov loop actions. Monte-Carlo simulations of these actions reveal that the mean-field analysis is a fairly good guide to the physics involved. Our Polyakov loop actions reproduce standard Yang-Mills observables well up to limitations due to the nearest-neighbor approximation.Comment: 14 pages, 10 figures, v2: typos correcte

Optimization of the Agar-gel Method for Isolation of Migrating Ascaris suum Larvae From the Liver and Lungs of Pigs

Experiments on use of an agar-gel method for recovery of migrating Ascaris suum larvae from the liver and lungs of pigs were conducted to obtain fast standardized methods. Subsamples of blended tissues of pig liver and lungs were mixed with agar to a final concentration of 1% agar and the larvae allowed to migrate out of the agar-gel into 0.9% NaCl at 38°C. The results showed that within 3 h more than 88% of the recoverable larvae migrated out of the liver agar-gel and more than 83% of the obtained larvae migrated out of the lung agar-gel. The larvae were subsequently available in a very clean suspension which reduced the sample counting time. Blending the liver for 60 sec in a commercial blender showed significantly higher larvae recovery than blending for 30 sec. Addition of gentamycin to reduce bacterial growth during incubation, glucose to increase larval motility during migration or ice to increase sedimentation of migrated larvae did not influence larvae recovery significantly