The relevance of center vortices

We show remnants of chiral symmetry breaking in the center-projected theory. We construct and study an unambiguous definition of center vortices.Comment: LATTICE99(confine), 3 pages, 3 figure

Order, Disorder and Confinement

Studying the order of the chiral transition for $N_f=2$ is of fundamental importance to understand the mechanism of color confinement. We present results of a numerical investigation on the order of the transition by use of a novel strategy in finite size scaling analysis. The specific heat and a number of susceptibilities are compared with the possible critical behaviours. A second order transition in the O(4) and O(2) universality classes are excluded. Substantial evidence emerges for a first order transition. Results are in agreement with those found by studying the scaling properties of a disorder parameter related to the dual superconductivity mechanism of color confinement.Comment: 7 pages, 11 figures. Talk given at the International Workshop on Quantum Chromodynamics: QCD@Work 2005, Conversano, Italy, 16-20 June 200

QCD, monopoles on the Lattice and gauge invariance

The number and the location of the monopoles observed on the lattice in QCD configurations happens to depend strongly on the choice of the gauge used to expose them, in contrast to the physical expectation that monopoles be gauge invariant objects. It is proved by use of the non abelian Bianchi identities (NABI) that monopoles are indeed gauge invariant, but the method used to detect them depends, in a controllable way, on the choice of the abelian projection. Numerical checks are presented.Comment: 3 pages, 1 figure. Presented at the Conference QUARK CONFINEMENT AND THE HADRON SPECTRUM IX, Madrid Aug.30-Sept.3 201

A test of first order scaling in Nf=2 QCD

We complete our analysis of Nf=2 QCD based on the lattice staggered fermion formulation. Using a series of Monte Carlo simulations at fixed (amq*Ls^yh) one is able to test the universality class with given critical exponent yh. This strategy has been used to test the O(4) universality class and it has been presented at the previous Lattice conferences. No agreement was found with simulations in the mass range amq=[0.01335,0.15] using lattices with Ls=16 up to 32 and Lt=4. With the same strategy, we now investigate the possibility of a first order transition using a new set of Monte Carlo data corresponding to yh=3 in the same mass and volume range as the one used for O(4). A substantial agreement is observed both in the specific heat scaling and in the scaling of the chiral condensate, while the chiral susceptibilities still presents visible deviation from scaling in the mass range explored.Comment: 5 pages, 6 figures, Presented at the XXV International Symposium on Lattice Field Theory, July 30 - August 4 2007, Regensburg, German

Two flavor QCD and confinement - II

This paper is part of a program of investigation of the chiral transition in Nf=2 QCD, started in Phys.Rev.D72:114510,2005. Progress is reported on the understanding of some possible systematic errors. A direct test of first order scaling is presented.Comment: 7 pages, 6 figure

The Spray/Load and Dative Alternations: Aligning VP Structure and Contextual Effects.

The theoretical and experimental work presented in this thesis investigates the spray/load and dative alternations. The purpose is to provide a comprehensive analysis of the alternations in terms of their syntactic structures and to account for how contextual information drives differences in the linear order of their VP arguments. This analysis shows that the syntactic structures of the spray/load and dative alternations are identical; each variant in an alternation is characterised by one of two available structures proposed in Janke and Neeleman (2012). Each structure is shown to respect a novel thematic hierarchy that is based on the value of binary feature clusters (Reinhart, 2000) rather than by direct reference to semantic labels. The choice of a particular structure is demonstrated to be affected by the non-semantic context in which the spray/load or dative sentence is generated. This is a consequence of the limited processing capacity of Working Memory and the allocation of attentional resources to a stimulus. Experimental data from an as yet untested variable of the visual context – the egocentric perception of distance – is found to interact with word order preferences of the alternations. I conclude that non-semantic contextual information interacts with the encoding of an event which ultimately has consequences for syntactic choices

On the phase diagram of the Higgs SU(2) model

The Higgs SU(2) model with fixed Higgs length is usually believed to have two different phases at high gauge coupling (\beta), separated by a line of first order transitions but not distinuguished by any typical symmetry associated with a local order parameter, as first proved by Fradkin and Shenker. We show that in regions of the parameter space where it is usually supposed to be a first order phase transition only a smooth crossover is in fact present.Comment: 6 pages, 6 figures. Talk presented at The XXVI International Symposium on Lattice Field Theory, July 14 - 19, 2008 - Williamsburg, Virginia, US

Deep carbon storage potential of buried floodplain soils.

Soils account for the largest terrestrial pool of carbon and have the potential for even greater quantities of carbon sequestration. Typical soil carbon (C) stocks used in global carbon models only account for the upper 1 meter of soil. Previously unaccounted for deep carbon pools (>1 m) were generally considered to provide a negligible input to total C contents and represent less dynamic C pools. Here we assess deep soil C pools associated with an alluvial floodplain ecosystem transitioning from agricultural production to restoration of native vegetation. We analyzed the soil organic carbon (SOC) concentrations of 87 surface soil samples (0-15 cm) and 23 subsurface boreholes (0-3 m). We evaluated the quantitative importance of the burial process in the sequestration of subsurface C and found our subsurface soils (0-3 m) contained considerably more C than typical C stocks of 0-1 m. This deep unaccounted soil C could have considerable implications for global C accounting. We compared differences in surface soil C related to vegetation and land use history and determined that flooding restoration could promote greater C accumulation in surface soils. We conclude deep floodplain soils may store substantial quantities of C and floodplain restoration should promote active C sequestration