Smeared Gauge Fixing

We present a new method of gauge fixing to standard lattice Landau gauge, Max Re Tr $\sum_{\mu,x}U_{\mu,x}$, in which the link configuration is recursively smeared; these smeared links are then gauge fixed by standard extremization. The resulting gauge transformation is simultaneously applied to the original links. Following this preconditioning, the links are gauge fixed again as usual. This method is free of Gribov copies, and we find that for physical parameters ($\beta \geq 2$ in SU(2)), it generally results in the gauge fixed configuration with the globally maximal trace. This method is a general technique for finding a unique minimum to global optimization problems.Comment: 3 pages, 4 PostScript figures; Poster presented at LAT9

Ugly American Hermeneutics

This article will appear in a Symposium on comparative legal hermeneutics that includes four articles by American scholars and four articles by Brazilian scholars. I argue that the ugly American hermeneutics exemplified in Justice Scalia\u27s opinion in District of Columbia v. Heller is unfortunate, even if we supplement Justice Scalia\u27s hermeneutical fantasy with the much more careful and balanced philosophical work by Larry Solum, Keith Whittington and other scholars. Nevertheless, the pragmatic work of interpretation by lawyers and judges in the day-to-day world of legal practice shows a plain-faced integrity of which we Americans can be proud

Pseudomorphic growth of InAs on misoriented GaAs for extending quantum cascade laser wavelength

The authors have studied the impact of epilayer strain on the deposition of InAs/GaAs on (100) and (111)B with 2 degrees offset toward 2-1-1 surfaces. Consequences of a 7% lattice mismatch between these orientations in the form of three-dimensional growth are less apparent for (111)B with 2 degrees offset toward 2-1-1 surfaces compared to (100). By exploring a range of molecular beam epitaxy process parameters for InAs/GaAs growth and utilizing scanning electron microscopy, atomic force microscopy, and Raman spectroscopy to evaluate the quality of these strained layers, the authors develop empirical models that describe the influence of the process conditions in regards to surface roughness with \u3e92% accuracy. The smoothest InAs/GaAs samples demonstrated average surface roughness of 0.08 nm for 10 um-squre areas, albeit at very low deposition rates. The authors have found the most important process conditions to be substrate temperature and deposition rate, leading us to believe that controlling diffusion length may be the key to reducing defects in severely strained structures. InGaAs/AlGaAs quantum cascade laser structures were also produced on (111)B with 2 degrees offset toward 2-1-1 to take advantage of the piezoelectric effect, and the modified laser transitions due to these effects were observed

More evidence of localization in the low-lying Dirac spectrum

We have extended our computation of the inverse participation ratio of low-lying (asqtad) Dirac eigenvectors in quenched SU(3). The scaling dimension of the confining manifold is clearer and very near 3. We have also computed the 2-point correlator which further characterizes the localization.Comment: presented at Lattice2005(Topology and Confinement), Dublin, July 25-30, 2005, 6 pages, 3 figures, to appear in Proceedings of Scienc

Hodge gauge fixing in three dimensions

A progress report on experiences with a gauge fixing method proposed in LATTICE 94 is presented. In this algorithm, an SU(N) operator is diagonalized at each site, followed by gauge fixing the diagonal (Cartan) part of the links to Coulomb gauge using the residual abelian freedom. The Cartan sector of the link field is separated into the physical gauge field $\alpha^{(f)}_\mu$ responsible for producing $f^{\rm Cartan}_{\mu\nu}$, the pure gauge part, lattice artifacts, and zero modes. The gauge transformation to the physical gauge field $\alpha^{(f)}_\mu$ is then constructed and performed. Compactness of the lattice fields entails issues related to monopoles and zero modes which are addressed.Comment: 4 pages Latex, 3 postscript figures, Poster presented at LATTICE96(topology

Was Slavery Unconstitutional Before the Thirteenth Amendment? Lysander Spooner’s Theory of Interpretation

In 1843, radical abolitionist William Lloyd Garrison called the Constitution of the United States, a covenant with death and an agreement with hell. Why? Because it sanctioned slavery, one of the greatest crimes that one person can commit against another. Slavery was thought by abolitionists to be a violation of the natural rights of man so fundamental that, as Lincoln once remarked: If slavery were not wrong, nothing is wrong. Yet the original U.S. Constitution was widely thought to have sanctioned this crime. Even today, many still believe that, until the ratification of the Thirteenth Amendment prohibiting involuntary servitude, slavery previously had been constitutional, and for this reason, the original Constitution was deeply flawed. But in 1845 one man disagreed with the conventional wisdom. That man insisted that slavery was not only a moral abomination; it was also unconstitutional. His name was Lysander Spooner and he defended this position in a book, entitled The Unconstitutionality of Slavery. While rejecting his conclusion, Garrison wrote of Spooner\u27s argument: We admit Mr. Spooner\u27s reasoning to be ingenious--perhaps, as an effort in logic, unanswerable. Historians of abolitionism know Spooner\u27s name, but lawyers, law professors and their students generally do not. This is a pity. For Lysander Spooner deserves a place of honor among American lawyers, both for the principles for which he stood against the crowd and for the brilliance with which he defended those principles. In this Essay, though the author will be unable to do his analysis complete justice, he wants to describe the method of constitutional interpretation that led Spooner to his conclusion about slavery. In many ways, Spooner\u27s interpretive approach has a very modern ring. In important respects, however, his approach is preferable to those commonly used today and worthy of study for this reason alone

Faithful Hermeneutics

This article was presented at the Annual Meeting of the Association of American Law Schools on January 9, 2009 as part of a panel on Scriptural and Constitutional Hermeneutics. The panel was co-sponsored by the Law and Religion Section, Section on Jewish Law, and Section on Islamic Law, and the papers will be published by the Michigan State Law Review. My article compares legal and religious hermeneutics by exploring the dual nature of what I term faithful hermeneutics. The ambiguity evoked by this phrase is intentional. On one hand, it suggests an investigation of the relationship between legal and religious interpretation by comparing hermeneutical activities undertaken by faithful adherents to these two different textual traditions. In this first sense, it is to compare how these practices are the hermeneutics of the faithful. On the other hand, the phrase suggests an analysis of how interpreters in these two traditions remain faithful to the nature of their practice. In this second sense, it is to compare how hermeneutics can be faithfully accomplished. My thesis is that these two senses of faithful hermeneutics are connected. The fact that it is faithful adherents who engage in the interpretive practice in large part defines how they can, and should, remain faithful to the interpretive enterprise. I anchor my argument in Hans-Georg Gadamer\u27s critique of historicism, in which he references the practices of legal and religious hermeneutics. Gadamer\u27s philosophical hermeneutics explains how faith is a prerequisite of understanding, even as understanding revitalizes and reshapes the faith one brings to a textual tradition. I then unfold the critical dimensions of faithful hermeneutics by comparing the work of Cardinal Joseph Ratzinger (later Pope Benedict XVI) and Gianni Vattimo on the Catholic tradition. I argue that these two thinkers display both the broad range and the non-methodological character of the critical insights of faithful hermeneutics. I conclude by suggesting that the parallels between religious and legal hermeneutics are instructive, but that we remember that it would be a mistake to conflate these two instances of faithful hermeneutics in our secular age

Abnormal Speech Motor Control in Individuals with 16p11.2 Deletions.

Speech and motor deficits are highly prevalent (>70%) in individuals with the 600 kb BP4-BP5 16p11.2 deletion; however, the mechanisms that drive these deficits are unclear, limiting our ability to target interventions and advance treatment. This study examined fundamental aspects of speech motor control in participants with the 16p11.2 deletion. To assess capacity for control of voice, we examined how accurately and quickly subjects changed the pitch of their voice within a trial to correct for a transient perturbation of the pitch of their auditory feedback. When compared to controls, 16p11.2 deletion carriers show an over-exaggerated pitch compensation response to unpredictable mid-vocalization pitch perturbations. We also examined sensorimotor adaptation of speech by assessing how subjects learned to adapt their sustained productions of formants (speech spectral peak frequencies important for vowel identity), in response to consistent changes in their auditory feedback during vowel production. Deletion carriers show reduced sensorimotor adaptation to sustained vowel identity changes in auditory feedback. These results together suggest that 16p11.2 deletion carriers have fundamental impairments in the basic mechanisms of speech motor control and these impairments may partially explain the deficits in speech and language in these individuals

The scaling dimension of low lying Dirac eigenmodes and of the topological charge density

As a quantitative measure of localization, the inverse participation ratio of low lying Dirac eigenmodes and topological charge density is calculated on quenched lattices over a wide range of lattice spacings and volumes. Since different topological objects (instantons, vortices, monopoles, and artifacts) have different co-dimension, scaling analysis provides information on the amount of each present and their correlation with the localization of low lying eigenmodes.Comment: Lattice2004(topology), Fermilab, June 21 - 26, 2004; 3 pages, 3 figure

B meson form factors from HQET simulations

We use simulations of heavy quark effective field theory to calculate the Isgur-Wise function, and we demonstrate the feasibility of calculating the matrix element for the B \to \pi + \leptons decay in the lattice heavy quark effective theory (HQET).Comment: 3 pages, 2 figures, talk presented at the lattice 97 conferenc