Structural Change in the U.S. Dairy Industry: Growth in Scale, Regional Shifts in Milk Production and Processing, and Internationalism

Structural changes in the U.S. dairy industry from the early 1980s to the late 1990s included familiar increases in concentration, industry adjustments to serve large supermarkets, the emergence of two national fluid milk firms (Suiza Foods and Dean Foods), and the emergence of two national dairy cooperatives (Dairy Farmers of America and Land O'Lakes, Inc.). Shifts in the location of milk production in the U.S. to the Western states have caused new dairy product manufacturing plants to locate in those states. This development promises to intensify battles over market share in the expanding U.S. cheese market between Western firms and Upper Midwestern firms. Foreign direct investment in the U.S. dairy industry--especially by European Union firms and a large Canadian firm--increased during the 1980s and 1990s. Facing challenges to expand dairy exports or shrink, the U.S. dairy industry probably will gravitate toward the latter unless government price support and trade policies change to increase price incentives for U.S. firms to export dairy products.

QCDSP: The first 64 nodes

We present a summary of the progress on QCDSP in the last year. QCDSP, Quantum Chromodynamics on Digital Signal Processors, is an inexpensive computer being built at Columbia that can achieve 0.8 teraflops for three million dollars.Comment: 4 pages, 1 figur

Unexpected Spin-Off from Quantum Gravity

We propose a novel way of investigating the universal properties of spin systems by coupling them to an ensemble of causal dynamically triangulated lattices, instead of studying them on a fixed regular or random lattice. Somewhat surprisingly, graph-counting methods to extract high- or low-temperature series expansions can be adapted to this case. For the two-dimensional Ising model, we present evidence that this ameliorates the singularity structure of thermodynamic functions in the complex plane, and improves the convergence of the power series.Comment: 10 pages, 4 figures; final, slightly amended version, to appear in Physica

Supersymmetry, shape invariance and the Legendre equations

In three space dimensions, when a physical system possesses spherical symmetry, the dynamical equations automatically lead to the Legendre and the associated Legendre equations, with the respective orthogonal polynomials as their standard solutions. This is a very general and important result and appears in many problems in physics (for example, the multipole expansion etc). We study these equations from an operator point of view, much like the harmonic oscillator, and show that there is an underlying shape invariance symmetry in these systems responsible for their solubility. We bring out various interesting features resulting from this analysis from the shape invariance point of view.Comment: 4 pages, 1 figure; to appear in PL

Localization and chiral symmetry in 2+1 flavor domain wall QCD

We present results for the dependence of the residual mass of domain wall fermions (DWF) on the size of the fifth dimension and its relation to the density and localization properties of low-lying eigenvectors of the corresponding hermitian Wilson Dirac operator relevant to simulations of 2+1 flavor domain wall QCD. Using the DBW2 and Iwasaki gauge actions, we generate ensembles of configurations with a $16^3\times 32$ space-time volume and an extent of 8 in the fifth dimension for the sea quarks. We demonstrate the existence of a regime where the degree of locality, the size of chiral symmetry breaking and the rate of topology change can be acceptable for inverse lattice spacings $a^{-1} \ge 1.6$ GeV.Comment: 59 Pages, 23 figures, 1 MPG linke

Orbital quantization in the high magnetic field state of a charge-density-wave system

A superposition of the Pauli and orbital coupling of a high magnetic field to charge carriers in a charge-density-wave (CDW) system is proposed to give rise to transitions between subphases with quantized values of the CDW wavevector. By contrast to the purely orbital field-induced density-wave effects which require a strongly imperfect nesting of the Fermi surface, the new transitions can occur even if the Fermi surface is well nested at zero field. We suggest that such transitions are observed in the organic metal $\alpha$-(BEDT-TTF)$_2$KHg(SCN)$_4$ under a strongly tilted magnetic field.Comment: 14 pages including 4 figure

Gap Domain Wall Fermions

I demonstrate that the chiral properties of Domain Wall Fermions (DWF) in the large to intermediate lattice spacing regime of QCD, 1 to 2 GeV, are significantly improved by adding to the action two standard Wilson fermions with supercritical mass equal to the negative DWF five dimensional mass. Using quenched DWF simulations I show that the eigenvalue spectrum of the transfer matrix Hamiltonian develops a substantial gap and that the residual mass decreases appreciatively. Furthermore, I confirm that topology changing remains active and that the hadron spectrum of the added Wilson fermions is above the lattice cutoff and therefore is irrelevant. I argue that this result should also hold for dynamical DWF and furthermore that it should improve the chiral properties of related fermion methods.Comment: 12 pages of text, 14 figures, added sect.6 on topology and reference