60,816 research outputs found
Instantiation in Trope Theory
The concept of instantiation is realized differently across a variety of metaphysical theories. A certain realization of the concept in a given theory depends on what roles are specified and associated with the concept and its corresponding term as well as what entities are suited to fill those roles. In this paper, the classic realization of the concept of instantiation in a one-category ontology of abstract particulars or tropes is articulated in a novel way and defended against unaddressed objections
Describing mixed spin-space entanglement of pure states of indistinguishable particles using an occupation number basis
Quantum mechanical entanglement is a resource for quantum computation,
quantum teleportation, and quantum cryptography. The ability to quantify this
resource correctly has thus become of great interest to those working in the
field of quantum information theory. In this paper, we show that all existing
entanglement measures but one fail important tests of fitness when applied to n
particle, m site states of indistinguishable particles, where n,m>=2. The
accepted method of measuring the entanglement of a bipartite system of
distinguishable particles is to use the von Neumann entropy of the reduced
density matrix of one half of the system. We show that expressing the full
density matrix using a site-spin occupation number basis, and reducing with
respect to that basis, gives an entanglement which meets all currently known
fitness criteria for systems composed of either distinguishable or
indistinguishable particles.
We consider an output state from a previously published thought experiment, a
state which is entangled in both spin and spatial degrees of freedom, and show
that the site entropy measure gives the correct total entanglement. We also
show how the spin-space entanglement transfer occurring within the apparatus
can be understood in terms of the transfer of probability from single-occupancy
to double-occupancy sectors of the density matrix.Comment: 2 figures; added Appendix A; added Figure 2; made changes to take
account of v2 of quant-ph/0105120; some typos remove
An Evening Spent with Bill van Zwet
Willem Rutger van Zwet was born in Leiden, the Netherlands, on March 31,
1934. He received his high school education at the Gymnasium Haganum in The
Hague and obtained his Masters degree in Mathematics at the University of
Leiden in 1959. After serving in the army for almost two years, he obtained his
Ph.D. at the University of Amsterdam in 1964, with Jan Hemelrijk as advisor. In
1965, he was appointed Associate Professor of Statistics at the University of
Leiden and promoted to Full Professor in 1968. He remained in Leiden until his
retirement in 1999, while also serving as Associate Professor at the University
of Oregon (1965), William Newman Professor at the University of North Carolina
at Chapel Hill (1990--1996), frequent visitor and Miller Professor (1997) at
the University of California at Berkeley, director of the Thomas Stieltjes
Institute of Mathematics in the Netherlands (1992--1999), and founding director
of the European research institute EURANDOM (1997--2000). At Leiden, he was
Dean of the School of Mathematics and Natural Sciences (1982--1984). He served
as chair of the scientific council and member of the board of the Mathematics
Centre at Amsterdam (1983--1996) and the Leiden University Fund (1993--2005).Comment: Published in at http://dx.doi.org/10.1214/08-STS261 the Statistical
Science (http://www.imstat.org/sts/) by the Institute of Mathematical
Statistics (http://www.imstat.org
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Person-Specific Methods for Characterizing the Course and Temporal Dynamics of Concussion Symptomatology: A Pilot Study.
Better characterization of acute concussion symptomatology is needed in order to advance clinical and scientific understanding of persistent concussion symptoms. This paper aims to illustrate a novel framework for conceptualizing, collecting, and analyzing concussion symptom data. To that end, we describe the temporal and structural dynamics of acute concussion symptoms at the individual-patient level. Ten recently concussion adolescents and young adults completed 20 days of ecological momentary assessment (EMA) of post-concussion symptoms. Follow-up assessments were completed at 3 months post-injury. Network modeling revealed marked heterogeneity across participants. In the overall sample, temporal patterns explained the most variance in light sensitivity (48%) and the least variance in vomiting (5%). About half of the participants had symptom networks that were sparse after controlling for temporal variation. The other individualized symptom networks were densely interconnected clusters of symptoms. Networks were highly idiosyncratic in nature, yet emotional symptoms (nervousness, emotional, sadness), cognitive symptoms (mental fogginess, slowness), and symptoms of hyperacusis (sensitivity to light, sensitivity to noise) tended to cluster together across participants. Person-specific analytic techniques revealed a number of idiosyncratic features of post-concussion symptomatology. We propose applying this framework to future research to better understand individual differences in concussion recovery
Investigation looking at the repeatability of 20 Society of Master Saddlers (SMS) qualified saddle fitters’ observations during static saddle fit
Saddle fit is widely considered to be a crucial factor for the health and performance of riding horses; however, there have been no studies looking at the agreement between professionals who fit and assess saddles. The aim of the study was to determine the agreement between Society of Master Saddlers (SMSs) qualified saddle fitters when statically fitting a saddle following the SMS guidelines. Twenty SMS qualified saddle fitter volunteers were recruited via social media and asked to statically assess the fit of the saddle following the “7 points of saddle fit” guidelines of the SMS in 10 horses. Descriptive statistics and Fleiss Kappa (as a measure of agreement beyond chance) were used to determine agreement between fitters. Agreement varied from slight to substantial between the different saddle assessment criteria with the assessment of overall saddle fit resulting in a fair agreement of k = 0.32. Substantial agreement was found for saddle clearance front (k = 0.66), top (k = 0.78), and rear (k = 0.81). Fair agreement was found for clearance of the saddle—side (k = 0.28) and how the girth straps line up with girth groove (k = 0.31) and panel contact (k = 0.38). Slight agreement was found for tree width and length (k = 0.12) and tree length (k = 0.12). Horse height in some criteria affected agreement. Agreement varied between the standard criteria. In cases where it was difficult to visually evaluate saddle fit, agreement was lower. Further work should aim to standardize the criteria which had suboptimal agreement
Observation of fine one-dimensionally disordered layers in silicon carbide
The improved resolution of synchrotron edge-topography is enabling thinner (less than 100 microns), silicon carbide crystals to be studied, and is providing a more detailed and wider database on polytype depth profiles. Fine long-period and one-dimensionally-disordered layers, 5-25 microns thick, can now be confidently resolved and are found to be very common features, often in association with high-defect density bands. These features are illustrated in this paper using three examples. A new long period polytype LPP (152H/456R) has been discovered and reported here for the first time
Integration of Technology in Math and Science Education – A Model for Teaching Elementary and Middle School Pre-Service Teachers
This paper describes the development and implementation of a course, Integration of Technology in Math and Science Education, to introduce elementary and middle school pre-service teachers to real technology skills that they can use in their future classrooms. Activities allowed the students to learn technology skills while using the Internet to enrich their content skills and share information with their fellow students. The course was designed to allow students to master a variety of technology skills, and see how these skills can be used appropriately in their future classrooms, while also increasing their comfort level to use the technology and reduce their resistance and anxiety to use it later in their real-time classrooms. During the class hands-on activities, the students became fluent at using the Internet for enrichment and communication, and at developing strategies for using their new skills to present SOL-relevant lesson plans. Students enter this course with very little in the way of educational technology skills, but leave with a teaching toolbox filled with new skills
Party finance reform as constitutional engineering? The effectiveness and unintended consequences of party finance reform in France and Britain
In both Britain and France, party funding was traditionally characterized by a laissez faire approach and a conspicuous lack of regulation. In France, this was tantamount to a 'legislative vacuum'. In the last two decades, however, both countries have sought to fundamentally reform their political finance regulation regimes. This prompted, in Britain, the Political Parties, Elections and Referendums Act 2000, and in France a bout of 'legislative incontinence' — profoundly transforming the political finance regime between 1988 and 1995. This article seeks to explore and compare the impacts of the reforms in each country in a bid to explain the unintended consequences of the alternative paths taken and the effectiveness of the new party finance regime in each country. It finds that constitutional engineering through party finance reform is a singularly inexact science, largely due to the imperfect nature of information, the limited predictability of cause and effect, and the constraining influence of non-party actors, such as the Constitutional Council in France, and the Electoral Commission in Britain
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