348 research outputs found
Ruliology: Linking Computation, Observers and Physical Law
Stephen Wolfram has recently outlined an unorthodox, multicomputational
approach to fundamental theory, encompassing not only physics but also
mathematics in a structure he calls The Ruliad, understood to be the entangled
limit of all possible computations. In this framework, physical laws arise from
the the sampling of the Ruliad by observers (including us). This naturally
leads to several conceptual issues, such as what kind of object is the Ruliad?
What is the nature of the observers carrying out the sampling, and how do they
relate to the Ruliad itself? What is the precise nature of the sampling? This
paper provides a philosophical examination of these questions, and other
related foundational issues, including the identification of a limitation that
must face any attempt to describe or model reality in such a way that the
modeller-observers are include
Use of the Jung/Myers Model of Personality Types to Identify and Engage with Individuals at Greatest Risk of Experiencing Depression and Anxiety
Depression is the leading cause of ill health and disability worldwide. Objectives were (1) to determine the strength of the association between personality type with depression and anxiety using the Preferred Communication Style Questionnaire (PCSQ©) and the Four-Item Patient Health Questionnaire for Depression and Anxiety (PHQ-4) and (2) evaluate the extent to which severity of depression and anxiety is associated with personality type. Data were collected via a self-administered online survey of 10,500. Chi-square analysis compared personality types and depression and anxiety. Practical significance was determined by calculating the percentage-from-expected score based on established statistics reflecting each personality type’s percentage in the US population. Personality type was strongly associated with both depression and anxiety with certain types at significantly greater risk than others. Findings can improve the research and clinical community’s understanding of the specific risk factors and triggers for depression and anxiety, and result in more efficacious, tailored treatment options
Pregeometry, Formal Language and Constructivist Foundations of Physics
How does one formalize the structure of structures necessary for the foundations of physics? This work is an attempt at conceptualizing the metaphysics of pregeometric structures, upon which new and existing notions of quantum geometry may find a foundation. We discuss the philosophy of pregeometric structures due to Wheeler, Leibniz as well as modern manifestations in topos theory. We draw attention to evidence suggesting that the framework of formal language, in particular, homotopy type theory, provides the conceptual building blocks for a theory of pregeometry. This work is largely a synthesis of ideas that serve as a precursor for conceptualizing the notion of space in physical theories. In particular, the approach we espouse is based on a constructivist philosophy, wherein ``structureless structures'' are syntactic types realizing formal proofs and programs. Spaces and algebras relevant to physical theories are modeled as type-theoretic routines constructed from compositional rules of a formal language. This offers the remarkable possibility of taxonomizing distinct notions of geometry using a common theoretical framework. In particular, this perspective addresses the crucial issue of how spatiality may be realized in models that link formal computation to physics, such as the Wolfram model
Evidence for the Gompertz Curve in the Income Distribution of Brazil 1978-2005
This work presents an empirical study of the evolution of the personal income
distribution in Brazil. Yearly samples available from 1978 to 2005 were studied
and evidence was found that the complementary cumulative distribution of
personal income for 99% of the economically less favorable population is well
represented by a Gompertz curve of the form , where
is the normalized individual income. The complementary cumulative
distribution of the remaining 1% richest part of the population is well
represented by a Pareto power law distribution . This
result means that similarly to other countries, Brazil's income distribution is
characterized by a well defined two class system. The parameters , ,
, were determined by a mixture of boundary conditions,
normalization and fitting methods for every year in the time span of this
study. Since the Gompertz curve is characteristic of growth models, its
presence here suggests that these patterns in income distribution could be a
consequence of the growth dynamics of the underlying economic system. In
addition, we found out that the percentage share of both the Gompertzian and
Paretian components relative to the total income shows an approximate cycling
pattern with periods of about 4 years and whose maximum and minimum peaks in
each component alternate at about every 2 years. This finding suggests that the
growth dynamics of Brazil's economic system might possibly follow a
Goodwin-type class model dynamics based on the application of the
Lotka-Volterra equation to economic growth and cycle.Comment: 22 pages, 15 figures, 4 tables. LaTeX. Accepted for publication in
"The European Physical Journal B
Cancer and thrombosis: Managing the risks and approaches to thromboprophylaxis
Patients with cancer are at increased risk of venous thromboembolism (VTE) compared with patients without cancer. This results from both the prothrombotic effects of the cancer itself and iatrogenic factors, such as chemotherapy, radiotherapy, indwelling central venous devices and surgery, that further increase the risk of VTE. Although cancer-associated thrombosis remains an important cause of morbidity and mortality, it is often underdiagnosed and undertreated. However, evidence is accumulating to support the use of low-molecular-weight heparins (LMWHs) in the secondary prevention of VTE in patients with cancer. Not only have LMWHs been shown to be at least as effective as coumarin derivatives in this setting, but they have a lower incidence of complications, including bleeding, and are not associated with the practical problems of warfarin therapy. Furthermore, a growing number of studies indicate that LMWHs may improve survival among patients with cancer due to a possible antitumor effect. Current evidence suggests that LMWHs should increasingly be considered for the long-term management of VTE in patients with cancer
Studying complex interventions : reflections from the FEMHealth project on evaluating fee exemption policies in West Africa and Morocco
Peer reviewedPublisher PD
Using space syntax and historical land-use data to interrogate narratives of high street ‘decline’ in two Greater London suburbs
The purpose of this paper is to provide some much needed theoretical grounding and historical-morphological context for the narratives of communal loss that recur in the reportage concerning the British high street. Given the topicality of this issue for policy-makers it is worth enquiring into precisely how far such narratives are in fact supported by a long-term perspective on historical changes in high street land uses in relation to the evolving spatial morphology of small town centres, in order to better distinguish the extent to which a further layer of socio-cultural explanation is required to account for the concern over ‘decline’. This research, undertaken as part of the EPSRC Adaptable Suburbs project at UCL, uses fully digitized historical maps, contemporary and historical land use data and space syntax analysis to identify historical-morphological parameters of change and continuity in and around two suburban high streets of Greater London since the nineteenth century: Surbiton and South Norwood. Drawing on Hillier and colleagues’ theory of ‘movement economy, the contemporary English high street, as it is represented in the case-study areas, emerges as a distinctive and resilient spatial morphology which has supported varied modes of land use over time. It concludes that the narrative of high street decline in part reflects a dominant focus on difficulties facing the UK retail sector and that a broader focus on the high street as a (re)generative social space rather than simply as a ‘retail attractor’ would allow for a broader appreciation of both its morphological and socio-economic capacities
On Empirical Equivalence and Duality
I argue that, on a judicious reading of two existing criteria--one syntactic and the other semantic--dual theories can be taken to be empirically equivalent. The judicious reading is straightforward, but leads to the surprising conclusion that very different-looking theories can have equivalent empirical content. And thus it shows how a widespread scientific practice, of interpreting duals as empirically equivalent, can be understood by a thus-far unnoticed feature of existing accounts of empirical equivalence
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