Evolution and Earth's Entropy

Entropy decreases on the Earth due to day/night temperature differences. This decrease exceeds the decrease in entropy on the Earth related to evolution by many orders of magnitude. Claims by creationists that science is somehow inconsistent with regard to evolution are thus show to be baseless.Comment: 2 page

Reference frames and rigid motions in relativity: Applications

The concept of rigid reference frame and of constricted spatial metric, given in the previous work [\emph{Class. Quantum Grav.} {\bf 21}, 3067,(2004)] are here applied to some specific space-times: In particular, the rigid rotating disc with constant angular velocity in Minkowski space-time is analyzed, a new approach to the Ehrenfest paradox is given as well as a new explanation of the Sagnac effect. Finally the anisotropy of the speed of light and its measurable consequences in a reference frame co-moving with the Earth are discussed.Comment: 13 pages, 1 figur

On the relation of Thomas rotation and angular velocity of reference frames

In the extensive literature dealing with the relativistic phenomenon of Thomas rotation several methods have been developed for calculating the Thomas rotation angle of a gyroscope along a circular world line. One of the most appealing concepts, introduced in \cite{rindler}, is to consider a rotating reference frame co-moving with the gyroscope, and relate the precession of the gyroscope to the angular velocity of the reference frame. A recent paper \cite{herrera}, however, applies this principle to three different co-moving rotating reference frames and arrives at three different Thomas rotation angles. The reason for this apparent paradox is that the principle of \cite{rindler} is used for a situation to which it does not apply. In this paper we rigorously examine the theoretical background and limitations of applicability of the principle of \cite{rindler}. Along the way we also establish some general properties of {\it rotating reference frames}, which may be of independent interest.Comment: 14 pages, 2 figure

The Relative Space: Space Measurements on a Rotating Platform

We introduce here the concept of relative space, an extended 3-space which is recognized as the only space having an operational meaning in the study of the space geometry of a rotating disk. Accordingly, we illustrate how space measurements are performed in the relative space, and we show that an old-aged puzzling problem, that is the Ehrenfest's paradox, is explained in this purely relativistic context. Furthermore, we illustrate the kinematical origin of the tangential dilation which is responsible for the solution of the Ehrenfest's paradox.Comment: 14 pages, 2 EPS figures, LaTeX, to appear in the European Journal of Physic

Technological learning and the accumulation of innovation capabilities: evidence from contract manufacturers in Brazil

A pesar de la profusión de estudios sobre aprendizaje como fuente de construcción de competencias tecnológicas en empresas, en general se ha observado dicha relación desde el punto de vista intraempresarial. En este artículo se examina el papel de los flujos interempresariales de conocimiento en la construcción de capacidades de producción y de innovación en filiales de empresas multinacionales del sector de tecnologías de la información y la comunicación (TIC) en Brasil, en el período 1996-2007. Con base en evidencias de primera mano, recogidas por medio de trabajo de campo, se comprobó en el estudio que las empresas investigadas se involucraron los últimos diez años en un proceso de acumulación de capacidades tecnológicas. Sin embargo, se encontró un alto grado de variabilidad entre las empresas en términos de la profundización de acumulación de capacidades tecnológicas, para actividades de producción y de innovación. Gran parte de esa variabilidad es explicada por la naturaleza e intensidad de los procesos interempresariales de aprendizaje desarrollados por las empresas. Este artículo, por tanto, contribuye al entendimiento del proceso de acumulación de capacidades tecnológicas en filiales de empresas multinacionales, en economías emergentes. El artículo también contradice generalizaciones comunes que atribuyen a ese tipo de empresa un papel pasivo, en términos de actividades tecnológicas, en el contexto de economías emergentes.A despeito da profusão de estudos sobre aprendizagem como fonte de construção de competências tecnológicas em empresas, a maioria tem examinado esse relacionamento pela perspectiva intraempresarial. Neste artigo, examina-se o papel dos fluxos interempresariais de conhecimento na construção de capacidades de produção e de inovação em empresas subsidiárias de multinacionais do setor de tecnologias de informação e de comunicação (TICs) do Brasil, no período de 1996 a 2007. Baseando-se em evidências de primeira mão, colhidas por meio de trabalho de campo, constatou-se que as empresas pesquisadas se engajaram ativamente nos últimos dez anos em um processo de acumulação de capacidades tecnológicas. Porém, encontrou-se no estudo alto grau de variabilidade entre as empresas estudadas, em termos da profundidade de acumulação de capacidades tecnológicas para atividades de produção e de inovação. Grande parte dessa variabilidade é explicada pela natureza e pela intensidade dos processos interempresariais de aprendizagem desenvolvidos pelas empresas. Este artigo contribui, portanto, para avançar no entendimento do processo de acumulação tecnológica em subsidiárias de empresas multinacionais em um contexto de economia emergente. Também contradiz generalizações comuns que atribuem a esse tipo de empresa um papel passivo quanto às atividades tecnológicas no contexto de economias emergentes.Despite the profusion of studies on learning as a means of building technological competence in firms, most have examined this relationship from an intra-firm perspective. This article examines the role of cross-firm knowledge flows to build production capacity and innovation in the subsidiaries of multinationals in the sector of information technology and communication (ITC) in Brazil, from 1996 to 2007. Based on first-hand evidence obtained in fieldwork, the study found that, for the last ten years, the companies surveyed have actively engaged in accumulating technological capabilities. However, the study also identified a high degree of variability across companies in terms of the depth of their technological capability accumulation. A substantial part of this variability can be explained by the role of crossorganizational learning processes. This article, therefore, helps to further our understanding of the process of technological accumulation in subsidiaries of multinationals in emerging economies. The study also contradicts common generalizations, according to which this kind of company plays a passive role in emerging economies when it comes to technological activities

The relativistic Sagnac Effect: two derivations

The phase shift due to the Sagnac Effect, for relativistic matter and electromagnetic beams, counter-propagating in a rotating interferometer, is deduced using two different approaches. From one hand, we show that the relativistic law of velocity addition leads to the well known Sagnac time difference, which is the same independently of the physical nature of the interfering beams, evidencing in this way the universality of the effect. Another derivation is based on a formal analogy with the phase shift induced by the magnetic potential for charged particles travelling in a region where a constant vector potential is present: this is the so called Aharonov-Bohm effect. Both derivations are carried out in a fully relativistic context, using a suitable 1+3 splitting that allows us to recognize and define the space where electromagnetic and matter waves propagate: this is an extended 3-space, which we call "relative space". It is recognized as the only space having an actual physical meaning from an operational point of view, and it is identified as the 'physical space of the rotating platform': the geometry of this space turns out to be non Euclidean, according to Einstein's early intuition.Comment: 49 pages, LaTeX, 3 EPS figures. Revised (final) version, minor corrections; to appear in "Relativity in Rotating Frames", ed. G. Rizzi and M.L. Ruggiero, Kluwer Academic Publishers, Dordrecht, (2003). See also http://digilander.libero.it/solciclo

Locality hypothesis and the speed of light

The locality hypothesis is generally considered necessary for the study of the kinematics of non-inertial systems in special relativity. In this paper we discuss this hypothesis, showing the necessity of an improvement, in order to get a more clear understanding of the various concepts involved, like coordinate velocity and standard velocity of light. Concrete examples are shown, where these concepts are discussed.Comment: 23 page

Technological learning and the accumulation of innovation capabilities: evidence from contract manufacturers in Brazil

A pesar de la profusión de estudios sobre aprendizaje como fuente de construcción de competencias tecnológicas en empresas, en general se ha observado dicha relación desde el punto de vista intraempresarial. En este artículo se examina el papel de los flujos interempresariales de conocimiento en la construcción de capacidades de producción y de innovación en filiales de empresas multinacionales del sector de tecnologías de la información y la comunicación (TIC) en Brasil, en el período 1996-2007. Con base en evidencias de primera mano, recogidas por medio de trabajo de campo, se comprobó en el estudio que las empresas investigadas se involucraron los últimos diez años en un proceso de acumulación de capacidades tecnológicas. Sin embargo, se encontró un alto grado de variabilidad entre las empresas en términos de la profundización de acumulación de capacidades tecnológicas, para actividades de producción y de innovación. Gran parte de esa variabilidad es explicada por la naturaleza e intensidad de los procesos interempresariales de aprendizaje desarrollados por las empresas. Este artículo, por tanto, contribuye al entendimiento del proceso de acumulación de capacidades tecnológicas en filiales de empresas multinacionales, en economías emergentes. El artículo también contradice generalizaciones comunes que atribuyen a ese tipo de empresa un papel pasivo, en términos de actividades tecnológicas, en el contexto de economías emergentes.A despeito da profusão de estudos sobre aprendizagem como fonte de construção de competências tecnológicas em empresas, a maioria tem examinado esse relacionamento pela perspectiva intraempresarial. Neste artigo, examina-se o papel dos fluxos interempresariais de conhecimento na construção de capacidades de produção e de inovação em empresas subsidiárias de multinacionais do setor de tecnologias de informação e de comunicação (TICs) do Brasil, no período de 1996 a 2007. Baseando-se em evidências de primeira mão, colhidas por meio de trabalho de campo, constatou-se que as empresas pesquisadas se engajaram ativamente nos últimos dez anos em um processo de acumulação de capacidades tecnológicas. Porém, encontrou-se no estudo alto grau de variabilidade entre as empresas estudadas, em termos da profundidade de acumulação de capacidades tecnológicas para atividades de produção e de inovação. Grande parte dessa variabilidade é explicada pela natureza e pela intensidade dos processos interempresariais de aprendizagem desenvolvidos pelas empresas. Este artigo contribui, portanto, para avançar no entendimento do processo de acumulação tecnológica em subsidiárias de empresas multinacionais em um contexto de economia emergente. Também contradiz generalizações comuns que atribuem a esse tipo de empresa um papel passivo quanto às atividades tecnológicas no contexto de economias emergentes.Despite the profusion of studies on learning as a means of building technological competence in firms, most have examined this relationship from an intra-firm perspective. This article examines the role of cross-firm knowledge flows to build production capacity and innovation in the subsidiaries of multinationals in the sector of information technology and communication (ITC) in Brazil, from 1996 to 2007. Based on first-hand evidence obtained in fieldwork, the study found that, for the last ten years, the companies surveyed have actively engaged in accumulating technological capabilities. However, the study also identified a high degree of variability across companies in terms of the depth of their technological capability accumulation. A substantial part of this variability can be explained by the role of crossorganizational learning processes. This article, therefore, helps to further our understanding of the process of technological accumulation in subsidiaries of multinationals in emerging economies. The study also contradicts common generalizations, according to which this kind of company plays a passive role in emerging economies when it comes to technological activities

Self-Reported Sleep Latency in Postmenopausal Women

The ain of this study was to access how self-reported sleep latency (SRSL) was affected by sleep habits, mood, and circadian rhythm in postmenopausal women. Subjects (n=384, 67.9±7.7 yr) completed sleep and mood questionnaires, sleep log and actigraphic data. The major urinary melatonin metabolite (6-sulphatoxymelatonin, aMT6s) was assayed in fractional urine specimens for two 24-hr intervals. Although SRSL (26.5±24.4 min) and actigraphic sleep latency (ASL; 27.8±20.0 min) were correlated (rs=0.361, p<0.001), the short SRSLs tended to be underestimated whereas the long SRSLs tended to be overestimated as compared to ASL. SRSL was positively correlated with the scales of insomnia, mood and hot flash, hypertension, use of anti-hypertensive drugs and the acrophase and the offset of aMT6s. SRSL was negatively correlated with the global assessment of functioning scale in DSM-IV (GAF scale), and light exposure and wrist activity. Multiple linear regression analysis showed that the best-fit model to predict SRSL was light exposure, GAF scale, and use of anti-hypertensive drugs. SRSL may be determined by psychophysiological factors as well as circadian rhythm function. Therapeutic approaches suggested for trouble falling asleep might include increased daylight exposure, improvements in general health, and modification of anti-hypertensive pharmacotherapy

Simultaneity and generalized connections in general relativity

Stationary extended frames in general relativity are considered. The requirement of stationarity allows to treat the spacetime as a principal fiber bundle over the one-dimensional group of time translations. Over this bundle a connection form establishes the simultaneity between neighboring events accordingly with the Einstein synchronization convention. The mathematics involved is that of gauge theories where a gauge choice is interpreted as a global simultaneity convention. Then simultaneity in non-stationary frames is investigated: it turns to be described by a gauge theory in a fiber bundle without structure group, the curvature being given by the Fr\"olicher-Nijenhuis bracket of the connection. The Bianchi identity of this gauge theory is a differential relation between the vorticity field and the acceleration field. In order for the simultaneity connection to be principal, a necessary and sufficient condition on the 4-velocity of the observers is given.Comment: RevTeX, 9 pages, 2 figures, 1 table. Previous title "The gauge nature of simultaneity". Classical and Quantum Gravity http://www.iop.org/EJ/journal/CQ