Quasiparticle interference and the interplay between superconductivity and density wave order in the cuprates

Scanning tunneling spectroscopy (STS) is a useful probe for studying the cuprates in the superconducting and pseudogap states. Here we present a theoretical study of the Z-map, defined as the ratio of the local density of states at positive and negative bias energies, which frequently is used to analyze STS data. We show how the evolution of the quasiparticle interference peaks in the Fourier transform Z-map can be understood by considering different types of impurity scatterers, as well as particle-hole asymmetry in the underlying bandstructure. We also explore the effects of density wave orders, and show that the Fourier transform Z-map may be used to both detect and distinguish between them.Comment: final version published in Phys. Rev.

Fermionic WIMPs and Vacuum Stability in the Scotogenic Model

We demonstrate that the condition of vacuum stability severely restricts scenarios with fermionic WIMP dark matter in the scotogenic model. The sizable Yukawa couplings that are required to satisfy the dark matter constraint via thermal freeze-out in these scenarios tend to destabilise the vacuum at scales below that of the heaviest singlet fermion, rendering the model inconsistent from a theoretical point of view. By means of a scan over the parameter space, we study the impact of these renormalisation group effects on the viable regions of this model. Our analysis shows that a fraction of more than 90% of the points compatible with all known experimental constraints - including neutrino masses, the dark matter density, and lepton flavour violation - is actually inconsistent.Comment: 8 pages, 6 figures; content matches published versio

“Statistical Judo”: The Rhetoric of Senate Inaction in the Judicial Appointment Process

This article first briefly summarizes the issues that arise in the lower-court judicial confirmation process, and examines how the issues differ from those that arise during the confirmation of Supreme Court justices. The article considers constitutionally-based differences as well as practical differences in Senate and Executive behavior that have developed during more than two centuries of judicial confirmations. The body of the article offers a chronological history and critique of the rhetoric of both Republican and Democratic senators in discussing lower-court confirmations during the 107th Congress. This congressional session, spanning the years 2001 to 2002, was a particularly interesting one for examining the lower-court nominations process. Much the rhetoric of the 107th Congress relies upon comparisons of then-current nomination success rates to earlier judicial confirmation rates from the Carter, Reagan, Bush I, and Clinton presidencies. Thus, by carefully analyzing the claims of senators concerning judicial appointments during the first Congressional term of Bush II’s presidency, the article is able to survey more than twenty years of Senate behavior with respect to lower-court confirmations. In doing so, the article identifies a number of “confirmation process fallacies” that senators have repeatedly relied upon in their efforts to score political points on confirmation issues. It also explains some “confirmation process relevancies” in hopes that future debates can be grounded in important considerations rather than trivial and irrelevant ones. Because the lower-court “confirmation mess” is sure to return to prominence in the Democrat-controlled Senate that will be constituted in early 2007, and following the 2008 presidential elections and beyond, the author hopes that the article will help establish a baseline for arguments about delays in the confirmation process, particularly when the White House and Senate are held by different political parties. Finally, the article offers some brief thoughts on which procedural aspects of the current judicial confirmation process likely contribute most to the problem of delay, and whether anything can, or even should, be done to modify those procedures

THE LAWYER DOTH PROTEST TOO MUCH, METHINKS: RECONSIDERING THE CONTEMPORANEOUS OBJECTION REQUIREMENT IN DEPOSITIONS

The time has come to eliminate the contemporaneous objection requirement for depositions. From the original 1938 framing of the Federal Rules of Civil Procedure (Rules) to the present, no one has recognized that the theory behind the contemporaneous objection rule in depositions, as drawn from pre-Rules equity practice, does not match the function of depositions in our post-Rules system of open discovery. Pre-Rules depositions in the federal courts were exclusively testimony-preservation devices, and never discovery tools. The common law and statutory procedural rules for pre-Rules depositions, including the contemporaneous objection rule, reflected this use . But when the original Federal Rules of Civil Procedure converted depositions into primarily fact-discovery devices, the older procedural rules were incorporated into the new Rules, nearly wholesale, and without consideration—and there they remain. In the last ten years, perceived problems with deposition practice have resulted in a number of modifications to the discovery rules, as well as other proposals to curb aggressive use of objections in depositions. Before 1993, in the federal civil system, the Rules did not specify the manner in which deposition objections were to be made, which led to a chorus of commentators decrying the prevalence of “speaking” and “coaching” objections. Revisions in 1993 to the Federal Rules of Civil Procedure for the first time required deposition objections to be made “concisely and in a non-argumentative and non-suggestive manner.” In 1999, the Texas state courts went so far as to limit all objections to deposition questions to two words, either “Objection, leading” or “Objection, form.” However, all of these modifications and proposals share the pathology of the original Rules: they fail to recognize the theoretical disconnect between antiquated testimony-preservation-focused procedural rules and the now-primary use of depositions as fact-discovery devices. Thus, the proposals have focused on “discovery abuse,” rather than addressing the real problem, which is a fundamental misconception of the proper, less-adversarial role of attorneys in depositions. Rather than issue prescriptions that treat the symptoms, surgical elimination of the contemporaneous objection rule will address the disease, and finally bring deposition practice into line with the theory of open discovery upon which its modern incarnation is based

ELITE SELECTION AND A CULTURE OF TRADITION IN FDNY SPECIAL OPERATIONS

The New York City Fire Department (FDNY) is a brand name in public safety. Like many high-reliability organizations, its specialized units carry out advanced and technical work. Expanded mission tasking, compensation, and training have made these assignments a career ladder, but the antiquated selection and assignment policy threaten the integrity of the selection and recruitment process. FDNY may improve its selection for special operations based on what similar organizations do. By reviewing them, specifically the armed services and commercial diving, two high-reliability organizations, this study compares selection methods to identify validated testing, determine criteria, and develop a selection construct that can maintain or improve current selection policies. Findings reveal that cognitive ability testing, physical ability assessments, and in-depth character evaluations used to make personnel selections could enhance FDNY. This thesis recommends that further development of selection models would be beneficial for the organization and defend the FDNY against claims of bias, favoritism, and discrimination. Lack of validation has already cost New York City and the FDNY legal fines. Validation studies identify areas of selection that need improvement so the FDNY could reinforce traditional selection criteria and establish new and validated ways of identifying and cultivating talent with the fire service.Civilian, FDNYApproved for public release. Distribution is unlimited

Danse Folatre : Dance Frolics

https://digitalcommons.library.umaine.edu/mmb-ps/1486/thumbnail.jp

Graphical Display of a Missile Endgame Scenario

Traditionally, computer programs to model and simulate air-to-air missile endgame engagements have focused on improving the underlying probability of kill models. This focus, however, understates the benefits of current computer graphics technology for visualization and direct manipulation of missile endgame parameters and building engagement understanding through real-time, three dimensional simulation of the endgame. Our research has been to develop a versatile simulation system to display the missile endgame parameters and allow graphical interaction with these parameters. This program also allows the user to view animated engagements of previously designed endgames. The current project scope is to provide user feedback of multiple fixed cone fuzes, warhead fragment trajectories, and target damage incurred by warhead detonation given a particular set of missile and target endgame encounter parameters. Our implementation, the AFIT Missile Endgame Simulator (AMES), achieves its goals using a Motif/Inventor graphical user interface to change engagement parameters through both text input and direct object manipulation. It also allows these engagements to be animated over time to help develop intuition about the objects\u27 interactions