627 research outputs found
Quantum Fields a la Sylvester and Witt
A structural explanation of the coupling constants in the standard model, i.e
the fine structure constant and the Weinberg angle, and of the gauge fixing
contributions is given in terms of symmetries and representation theory. The
coupling constants are normalizations of Lorentz invariantly embedded little
groups (spin and polarization) arising in a harmonic analysis of quantum vector
fields. It is shown that the harmonic analysis of massless fields requires an
extension of the familiar Fourier decomposition, containing also indefinite
unitary nondecomposable time representations. This is illustrated by the
nonprobabilistic contributions in the electromagnetic field.Comment: 18 pages LaTeX file (62 kB), all macros are include
Realizations of Causal Manifolds by Quantum Fields
Quantum mechanical operators and quantum fields are interpreted as
realizations of timespace manifolds. Such causal manifolds are parametrized by
the classes of the positive unitary operations in all complex operations, i.e.
by the homogenous spaces \D(n)=\GL(\C^n_\R)/\U(n) with for mechanics
and for relativistic fields. The rank gives the number of both the
discrete and continuous invariants used in the harmonic analysis, i.e. two
characteristic masses in the relativistic case. 'Canonical' field theories with
the familiar divergencies are inappropriate realizations of the real
4-dimensional causal manifold \D(2). Faithful timespace realizations do not
lead to divergencies. In general they are reducible, but nondecomposable - in
addition to representations with eigenvectors (states, particle) they
incorporate principal vectors without a particle (eigenvector) basis as
exemplified by the Coulomb field.Comment: 36 pages, latex, macros include
Management of contaminants in low permeability media
2014 Summer.Includes bibliographical references.To view the abstract, please see the full text of the document
Komplementäre Therapieverfahren in der Onkologie: Homöopathie
Zusammenfassung: Homöopathische Behandlungen werden in deutschsprachigen, aber auch in anderen Ländern von Krebspatienten häufig und z.T. über längere Zeiträume in Anspruch genommen. Prospektive Beobachtungsstudien zur Anwendung bei den verschiedensten Erkrankungen weisen in der Regel auf einen Nutzen der homöopathischen Behandlung hin. Die vorliegenden randomisierten Therapiestudien und deren Ergebnisse werden in den bisher publizierten Übersichtsarbeiten und Metaanalysen kontrovers beurteilt. Zur Anwendung bei Patienten mit einer Tumorerkrankung liegen bis heute nur relativ wenige wissenschaftliche Untersuchungen vor. Sie werden in der vorliegenden Arbeit dargestellt und diskutiert. Einzelne Studien zeigen günstige Effekte auf Nebenwirkungen antitumoraler Therapien sowie auf die Lebensqualität tumorkranker Patienten. Diese Ergebnisse bedürfen aber einer Replikation in methodisch angemessenen und aussagekräftigen Folgestudien. Zur Frage einer möglichen antitumoralen Wirksamkeit sind bisher keine vergleichenden Studien durchgeführt worden. In den derzeit publizierten Studien wurden keine ernsten unerwünschten Wirkungen und keine Interaktionen mit konventionellen antitumoralen Therapien berichte
Hiroshima. At the Intersection of Sciences, History, and Personal Narratives. A Personal Reflection.
In the city of Hiroshima, Japan, sciences, history, and personal narratives meet. Atomic bomb survivors became the keepers of this town’s history and one of the most tragic chapters in the history of humankind; and as their voices fade to old age and death, there is a sense of urgency to keep their narratives alive. These are my personal reflections
Systematic reviews of complementary therapies – an annotated bibliography. Part 2: Herbal medicine
Background Complementary therapies are widespread but controversial. We aim to provide a comprehensive collection and a summary of systematic reviews of clinical trials in three major complementary therapies (acupuncture, herbal medicine, homeopathy). This article is dealing with herbal medicine. Potentially relevant reviews were searched through the register of the Cochrane Complementary Medicine Field, the Cochrane Library, Medline, and bibliographies of articles and books. To be included articles had to review prospective clinical trials of herbal medicines; had to describe review methods explicitly; had to be published; and had to focus on treatment effects. Information on conditions, interventions, methods, results and conclusions was extracted using a pre-tested form and summarized descriptively. Results From a total of 79 potentially relevant reviews pre-selected in the screening process 58 met the inclusion criteria. Thirty of the reports reviewed ginkgo (for dementia, intermittent claudication, tinnitus, and macular degeneration), hypericum (for depression) or garlic preparations (for cardiovascular risk factors and lower limb atherosclerosis). The quality of primary studies was criticized in the majority of the reviews. Most reviews judged the available evidence as promising but definitive conclusions were rarely possible. Conclusions Systematic reviews are available on a broad range of herbal preparations prescribed for defined conditions. There is very little evidence on the effectiveness of herbalism as practised by specialist herbalists who combine herbs and use unconventional diagnosis
Trends of Medicinal Plant Use over the Last 2000 Years in Central Europe
Medicinal plant knowledge in Central Europe can be traced back from the present to antiquity, through written sources. Approximately 100 medicinal plant taxa have a history of continuous use. In this paper, we focus on use patterns over time and the link between historical and traditional uses with the current scientific evidence. We discuss our findings against the backdrop of changing eras and medicinal concepts. Based on use-records from totally 16 historical, popular and scientific herbals, we analyze how use categories of 102 medicinal plant taxa developed over time. Overall, 56 of the 102 taxa maintained continuous use throughout all time periods. For approximately 30% of the continuous uses, scientific evidence supporting their use exists, compared to 11% for recently added uses and 6% for discontinuous uses. Dermatology and gastroenterology are use categories that are relevant across all time periods. They are associated with a high diversity of medicinal taxa and continuously used medicinal species with scientific evidence. Antidotes, apotropaic (protective) magic, and humoral detoxification were important use categories in the past. New applications reflecting biomedical progress and epidemiological challenges are cardiovascular and tonic uses. Changes in medicinal concepts are mirrored in plant use and specifically in changes in the importance of use categories. Our finding supports the concept of social validation of plant uses, i.e., the assumption that longstanding use practice and tradition may suggest efficacy and safety
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