Approximating the Sachdev-Ye-Kitaev model with Majorana wires

The Sachdev-Ye-Kitaev (SYK) model describes a collection of randomly interacting Majorana fermions that exhibits profound connections to quantum chaos and black holes. We propose a solid-state implementation based on a quantum dot coupled to an array of topological superconducting wires hosting Majorana zero modes. Interactions and disorder intrinsic to the dot mediate the desired random Majorana couplings, while an approximate symmetry suppresses additional unwanted terms. We use random matrix theory and numerics to show that our setup emulates the SYK model (up to corrections that we quantify) and discuss experimental signatures.Comment: 7 pages, 2 figure

Competition and market structure in local real estate markets

The persistence of the standard six percent real estate sales commission across markets and over time calls into question the competitiveness of the residential real estate brokerage industry. While there is anecdotal evidence that some local real estate markets are fairly concentrated, no systematic study of market structures has been conducted. We have collected primary data on the number and market shares of real estate brokers in a variety of small, medium, and large real estate markets across the U.S. for 2007 and 2009. In addition to these cross sectional data, we have also collected longitudinal data on the size distribution of firms for Louisville, KY for a nine-year period. In our cross-sectional analysis of medium and large markets, we find no evidence that market concentration might create problems for competition. We do find that small markets on average have higher HHI’s than medium and large markets. The longitudinal analysis reveals that many small brokers are in and out of the market, selling a house or two one year and selling zero houses the next year.HHI; real estate brokerage competition; Herfindahl-Hirschman Index

Designing dark energy afterglow experiments

Chameleon fields, which are scalar field dark energy candidates, can evade fifth force constraints by becoming massive in high-density regions. However, this property allows chameleon particles to be trapped inside a vacuum chamber with dense walls. Afterglow experiments constrain photon-coupled chameleon fields by attempting to produce and trap chameleon particles inside such a vacuum chamber, from which they will emit an afterglow as they regenerate photons. Here we discuss several theoretical and systematic effects underlying the design and analysis of the GammeV and CHASE afterglow experiments. We consider chameleon particle interactions with photons, Fermions, and other chameleon particles, as well as with macroscopic magnetic fields and matter. The afterglow signal in each experiment is predicted, and its sensitivity to various properties of the experimental apparatus is studied. Finally, we use CHASE data to exclude a wide range of photon-coupled chameleon dark energy models.Comment: 29 pages, 31 figures, 1 tabl

Moving Difference (MDIFF) Non-adiabatic Rapid Sweep (NARS) EPR of Copper(II)

Non-adiabatic rapid sweep (NARS) EPR spectroscopy has been introduced for application to nitroxide-labeled biological samples (Kittell et al., 2011). Displays are pure absorption, and are built up by acquiring data in spectral segments that are concatenated. In this paper we extend the method to frozen solutions of copper-imidazole, a square planar copper complex with four in-plane nitrogen ligands. Pure absorption spectra are created from concatenation of 170 5-gauss segments spanning 850 G at 1.9 GHz. These spectra, however, are not directly useful since nitrogen superhyperfine couplings are barely visible. Application of the moving difference (MDIFF) algorithm to the digitized NARS pure absorption spectrum is used to produce spectra that are analogous to the first harmonic EPR. The signal intensity is about four times higher than when using conventional 100 kHz field modulation, depending on line shape. MDIFF not only filters the spectrum, but also the noise, resulting in further improvement of the SNR for the same signal acquisition time. The MDIFF amplitude can be optimized retrospectively, different spectral regions can be examined at different amplitudes, and an amplitude can be used that is substantially greater than the upper limit of the field modulation amplitude of a conventional EPR spectrometer, which improves the signal-to-noise ratio of broad lines

Evaluating the Efficacy and Acceptability of Videoconferencing in School-Based Behavioral Consultation

School-based behavioral consultation is a way of providing psychological services to students through their teachers. This indirect service delivery model has been shown to be effective for improving academic and behavioral concerns. Typically, school-based behavioral consultation is conducted face-to-face (in-vivo) between consultants (psychologists) and consultee’s (teachers); however, current technologies have provided an alternative medium to communicate, via videoconferencing. Videoconferencing has been shown to be an effective alternative to face-to-face communication across many different practice domains and applications. Videoconferencing in schools, particularly for school-based behavioral consultation, may be a viable alternative. The proposed study evaluated the efficacy and acceptability of videoconferencing with teachers as an alternative means of conducting the problem identification interview of school-based behavioral consultation. A school psychology doctoral student interviewed teachers on two occasions (face-to-face and via videoconferencing) to obtain information about student problem behavior. The videoconferencing interviews were conducted across iPads using the videoconferencing software FaceTime. All interviews were video recorded and transcribed into text to code verbalizations, using the Consultation Analysis Record (CAR). Frequencies of verbalizations were totaled on the Consultation Analysis checklist (CAC) into 14 required categories. Data from the CAC was used to evaluate the efficacy of the interviews. Additionally, teachers completed two brief measures, the Fast Form of the Technology Acceptability Model (FF-TAM) and the Distance Communication Comfort Scale (DCCS) pre and post interviews. Data from The FF-TAM and DCCS was used to evaluate the acceptability of videoconferencing. Finally, moderators of the acceptability of videoconferencing were evaluated using a multiple regression analysis

An Analysis of the Alteration of Style During the Later Old Kingdom and Late Eighteenth Dynasty

Throughout Ancient Egypt\u27s history, the artistic style used in rendering human forms has been altered on multiple occasions for varying reasons. In three cases, during the later Old Kingdom, the late reign of Amenhotep III, and the Amarna period, it appears that the alterations of style can be attributed to similar religious motivations. Moreover, these styles similarly render characteristics of the body in a childlike manner. Each of these periods is discussed, identifying important characteristics that define each as a separate style type and noting the specific religious motivations that inspired them. In each instance, it appears that the paedomorphic features associated with these styles reflect the emphasis on daily and eternal rejuvination linked with the solar deities Ra and the Aten, and the chthonic deity Osiris, who rose to national importance during these periods

The Impact of Online Influence Strategies on Consumer Response and Privacy Expectations

Identifying effective strategies for encouraging individuals to disclose their personal information on the Internet is important for marketers. In today\u27s informationbased economy, access to consumer data is imperative for organizations in conducting marketing activities. However, the extant privacy literature has found conflicting results regarding the effectiveness of safety cues (e.g., privacy policies) and rewards (e.g., discounts) for encouraging consumers to provide their personal information to Web sites (Andrade et al. 2002). There is also scant research on the implications of compensating consumers for their information, and its subsequent impact on privacy control expectations. This dissertation consists of two essays that examine how consumers respond to marketers\u27 strategies for encouraging self-disclosure on the Internet, and how these strategies affect expectations for privacy control. Essay 1 employs regulatory focus theory for investigating the impact of consumers\u27 goals (privacy protection vs. acquisition of benefits) on how they respond to marketers’ online influence strategies and brand reputation. The use of safety cues, rewards, and brand reputation have been identified in vii the privacy literature as important factors that influence consumers\u27 trust, privacy concern, and willingness to provide personal information (Milne and Culnan 2004). Essay 2 draws on theories of social exchange and social contracts for examining how the value and type of compensation received influences the degree to which consumers believe they own the information provided to marketers and their expectations for control over how their information is used. Although consumers frequently trade their personal information for benefits online, it has been suggested in the privacy literature that the point at which consumers own and control information about themselves and when that information becomes the property of marketers is unclear (Sheehan and Hoy 2000). This dissertation employs a mixed methods approach that includes a series of scenario-based experiments using survey panel data, and in-depth interviews. The results of essay 1 provide evidence of the importance of consumer goals in decisions to disclose personal information to marketers. Findings from essay 2 reveal that privacy exchanges may affect the degree to which consumers believe ownership and control over their information is shared with marketers