339 research outputs found
Thermal noise limitations to force measurements with torsion pendulums: Applications to the measurement of the Casimir force and its thermal correction
A general analysis of thermal noise in torsion pendulums is presented. The
specific case where the torsion angle is kept fixed by electronic feedback is
analyzed. This analysis is applied to a recent experiment that employed a
torsion pendulum to measure the Casimir force. The ultimate limit to the
distance at which the Casimir force can be measured to high accuracy is
discussed, and in particular the prospects for measuring the thermal correction
are elaborated upon.Comment: one figure, five pages, to be submitted to Phys Rev
Vitalism in Early Modern Medical and Philosophical Thought
Vitalism is a notoriously deceptive term. It is very often defined as the view, in biology, in early modern medicine and differently, in early modern philosophy, that living beings differ from the rest of the physical universe due to their possessing an additional âlife-forceâ, âvital principleâ, âentelechyâ, enormon or Ă©lan vital. Such definitions most often have an explicit pejorative dimension: vitalism is a primitive or archaic view, that has somehow survived the emergence of modern science (the latter being defined in many different ways, from demystified Cartesian reductionism to experimental medicine, biochemistry or genetics: Cimino and Duchesneau eds. 1997, Normandin and Wolfe eds. 2013). Such dismissive definitions of vitalism are meant to dispense with argument or analysis.
Curiously, the term has gained some popularity in English-language scholarship on early modern philosophy in the past few decades, where it is used without any pejorative dimension, to refer to a kind of âactive matterâ view, in which matter is not reducible to the (mechanistic) properties of size, shape and motion, possessing instead some internal dynamism or activity (see e.g. James 1999, Boyle 2018, Borcherding forthcoming). The latter meaning is close to what the Cambridge Platonist Ralph Cudworth termed âhylozoismâ, namely the attribution of life, agency or mind to matter, and he implicitly targeted several figures I shall mention here, notably Margaret Cavendish and Francis Glisson, for holding this view. However, one point I shall make in this entry is that when vitalism first appears by name, and as a self-designation, in the Montpellier School (associated with the Faculty of Medicine at the University of Montpellier, in the second half of the eighteenth century; thus vitalisme appears first, followed shortly thereafter by Vitalismus in German, with âvitalismâ appearing in English publications only in the early nineteenth century: Toepfer 2011), it is quite different from both the more âsupernaturalâ view described above â chiefly espoused by its rather obsessive opponents â and from the more neutral, but also de-biologized philosophical view (that of e.g. Cavendish or Conway who are, broadly speaking naturalists). Rather than appealing to a metaphysics of vital force, or of self-organizing matter, this version of vitalism, which I shall refer to as âmedical vitalismâ, seems to be more of a âsystemicâ theory: an attempt to grasp and describe top-level (âorganizationalâ, âorganismicâ, âholisticâ) features of living systems (Wolfe 2017, 2019).
In this entry I seek to introduce some periodization in our thinking about early modern (and Enlightenment) vitalism, emphasizing the difference between the seventeenth-century context and that of the following generations â culminating in the ideas of the Montpellier School. This periodization should also function as a kind of taxonomy or at least distinction between some basic types of vitalism. As I discuss in closing, these distinctions can cut across the texts and figures we are dealing with, differently: metaphysical vs. non-metaphysical vitalism, philosophical vs. medical vitalism, medical vs. âembryologicalâ vitalism, and so on. A difference I can only mention but not explore in detail is that the more medically grounded, âorganismicâ vitalism is significantly post-Cartesian while the more biological/embryological vitalism is, inasmuch as it is a dynamic, self-organizing matter theory, an extension of Renaissance ideas (chymiatry, Galenism and in general theories of medical spirits).
I examine successively vitalismâs Renaissance prehistory, its proliferation as âvital matter theoryâ in seventeenth-century England (in authors such as Cavendish, Conway and Glisson, with brief considerations on Harvey and van Helmont), and its mature expression in eighteenth-century Montpellier (notably with Bordeu and MĂ©nuret de Chambaud)
Organisational participation and women - an attitude problem?
Employee participation is a dynamic and contested area of organisational behaviour, attracting continuing academic, practitioner and policy interest and debate. This chapter focuses on organisational participation and women
Phenomenology of the Lense-Thirring effect in the Solar System
Recent years have seen increasing efforts to directly measure some aspects of
the general relativistic gravitomagnetic interaction in several astronomical
scenarios in the solar system. After briefly overviewing the concept of
gravitomagnetism from a theoretical point of view, we review the performed or
proposed attempts to detect the Lense-Thirring effect affecting the orbital
motions of natural and artificial bodies in the gravitational fields of the
Sun, Earth, Mars and Jupiter. In particular, we will focus on the evaluation of
the impact of several sources of systematic uncertainties of dynamical origin
to realistically elucidate the present and future perspectives in directly
measuring such an elusive relativistic effect.Comment: LaTex, 51 pages, 14 figures, 22 tables. Invited review, to appear in
Astrophysics and Space Science (ApSS). Some uncited references in the text
now correctly quoted. One reference added. A footnote adde
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How being appreciative creates change â theory in practice from health and social care in Scotland
This paper develops understanding of appreciative action research that generates curiosity and motivation as a better platform for collaborative change. Blending theory and practice it draws on the example of the My Home Life leadership programme in Scotland that explores the concepts and approaches of âCaring Conversationsâ and âplayful provocationâ in care homes for older people. The paper shows how they expand notions of appreciation and help people to deepen inquiry, explore values, acknowledge and express emotion without dispute or judgement, articulate tacit knowledge and give voice to things previously thought to be âunsayableâ. We explore how these generative approaches act as a powerful positive âdisruptionâ that brings existing relationships to life, supports a positive attitude to risk-taking and helps to devise new approaches to the local design and testing of approaches to problems.
Ultimately these approaches play an important part in developing understanding of how to do appreciative action research to enhance relationships and more strengths or assets-based and collaborative ways of working and so, to develop new possibilities for changing social systems and a more future-making orientation to action research
Participant Observation as Ethnography or Ethnography as Participant Observation in Organizational Research
There is a strong tradition of observational research in most areas of the social sciences, especially in Anthropology and Sociology. However, in business and management research observation is often seen as a poor relative to questionnaire surveys and qualitative interviewing. This chapter discusses the use of observational techniques especially for less experienced researchers planning their first major investigation, exploring the difference between participant and non-participant approaches, different techniques of data collection, recording and analysis. Rather than seeking to provide a full guide to conducting participant observation, an impractical task in a single chapter, this offering discusses some of the key issues facing researchers in Business and Management who choose to conduct this sort of research, exploring different approaches to participant observation and some of the ethical and practical challenges associated with the collection and analysis of observational data. The chapter draws on the authorâs experience of conducting participant observation in organizations with examples of both employee (Sandiford and Seymour, 2002; Seymour and Sandiford, 2013) and customer perspectives (Sandiford and Divers, 2011). It will also draw from âclassicâ observational studies such as Mars and Nicod (1984) and more recent examples such as Watson and Watson (2012).Peter John Sandifor
Photon and Graviton Mass Limits
Efforts to place limits on deviations from canonical formulations of
electromagnetism and gravity have probed length scales increasing dramatically
over time.Historically, these studies have passed through three stages: (1)
Testing the power in the inverse-square laws of Newton and Coulomb, (2) Seeking
a nonzero value for the rest mass of photon or graviton, (3) Considering more
degrees of freedom, allowing mass while preserving explicit gauge or
general-coordinate invariance. Since our previous review the lower limit on the
photon Compton wavelength has improved by four orders of magnitude, to about
one astronomical unit, and rapid current progress in astronomy makes further
advance likely. For gravity there have been vigorous debates about even the
concept of graviton rest mass. Meanwhile there are striking observations of
astronomical motions that do not fit Einstein gravity with visible sources.
"Cold dark matter" (slow, invisible classical particles) fits well at large
scales. "Modified Newtonian dynamics" provides the best phenomenology at
galactic scales. Satisfying this phenomenology is a requirement if dark matter,
perhaps as invisible classical fields, could be correct here too. "Dark energy"
{\it might} be explained by a graviton-mass-like effect, with associated
Compton wavelength comparable to the radius of the visible universe. We
summarize significant mass limits in a table.Comment: 42 pages Revtex4. This version contains corrections and changes
contained in the published version, Rev. Mod. Phys. 82, 939-979 (2010), with
a few addition
Bringing History into the Study of Routines: Contextualizing Performance
The focus on routines as âgenerative systemsâ often portrays them as patterns of action relatively divorced from their context. History can help to supply a deeper and richer context, showing how routines are connected to broader structural and cultural factors. But it also shows that routines themselves have a history. This is explored using the illustration of the history of one particular organizational routine, that of the visitation of local organizational units by central church bodies, in three times and places: fifteenth century Italy, eighteenth century England and eighteenth century Scotland. This illustration shows that similar routines can be found but these are given very different inflections by the broader social, cultural and political context. Attention is drawn in particular to the
differential involvement of lay actors and the implications for broader impacts. The case is made for analytical narratives of emergence of routines which can reconnect organizational routines both with their own history and with their broader context
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