438 research outputs found
Search for light-speed anisotropies using Compton scattering of high-energy electrons
Based on the high sensitivity of Compton scattering off ultra relativistic
electrons, the possibility of anisotropies in the speed of light is
investigated. The result discussed in this contribution is based on the
gamma-ray beam of the ESRF's GRAAL facility (Grenoble, France) and the search
for sidereal variations in the energy of the Compton-edge photons. The absence
of oscillations yields the two-sided limit of 1.6 x 10^{-14} at 95 % confidence
level on a combination of photon and electron coefficients of the minimal
Standard Model Extension (mSME). This new constraint provides an improvement
over previous bounds by one order of magnitude.Comment: Talk presented at the Fifth Meeting on CPT and Lorentz Symmetry,
University of Indiana, June 28-July 2, 201
Gravitational resonance spectroscopy with an oscillating magnetic field gradient in the GRANIT flow through arrangement
Gravitational resonance spectroscopy consists in measuring the energy
spectrum of bouncing ultracold neutrons above a mirror by inducing resonant
transitions between different discrete quantum levels. We discuss how to induce
the resonances with a flow through arrangement in the GRANIT spectrometer,
excited by an oscillating magnetic field gradient. The spectroscopy could be
realized in two distinct modes (so called DC and AC) using the same device to
produce the magnetic excitation. We present calculations demonstrating the
feasibility of the newly proposed AC mode
Scheduling multiprocessor tasks with genetic algorithms
In the multĂprocessor schedulĂng problem a given program is to be scheduled in a given multiprocessor system such that the program 's execution time is minimized. This problem being very hard to solve exactly, many heuristic methods for finding a suboptimal schedule exist. We propose a new combined approach, where a genetic algorithm is improved with the introduction of some knowledge about the scheduling problem represented by the use of a list heuristic in the crossover and mutatĂon genetic operations. This knowledge-augmented genetic approach is empirically compared with a "pure" genetic algorithm and with a "pure" list heuristic, both from the literature. Results of the experiments carried out with synthetic instances of the scheduling problem show that our knowledge-augmented algorithm produces much better results in terms
of quality of solutions, although being slower in terms of execution time
Frequency shifts in gravitational resonance spectroscopy
Quantum states of ultracold neutrons in the gravitational field are to be
characterized through gravitational resonance spectroscopy. This paper
discusses systematic effects that appear in the spectroscopic measurements. The
discussed frequency shifts, which we call Stern-Gerlach shift, interference
shift, and spectator state shift, appear in conceivable measurement schemes and
have general importance. These shifts have to be taken into account in
precision experiments
Une « femme libérée » ?
NĂ©e en 1943 Ă Alger, AndrĂ©e Job-Querzola poursuit des Ă©tudes de lettres Ă Aix-en-Provence puis Ă Paris dans les annĂ©es 1960. Devenue enseignante, elle gravite dans la mouvance fĂ©ministe et dâextrĂȘme gauche et participe activement aux Ă©vĂ©nements de Mai. MarquĂ©e par les luttes fĂ©ministes des annĂ©es 1970, en particulier celles du MLF, du MLAC, du MFPF, elle souhaite rendre hommage aux femmes de sa gĂ©nĂ©ration â « une gĂ©nĂ©ration rebelle » qui, selon elle, sonne le glas de « gĂ©nĂ©rations de femmes f..
Raphaëlle Branche & Fabrice Virgili (dir.), Viols en temps de guerre
Issu dâun colloque qui a rĂ©uni en 2009 de nombreux chercheuses et chercheurs en sciences humaines (anthropologie, sociologie, histoire, philosophie, droitâŠ), ce livre sâempare dâun sujet assez peu Ă©tudiĂ© jusquâici dans lâhistoire des guerres : les viols. DĂšs lâintroduction, RaphaĂ«lle Branche et Fabrice Virgili soulignent quâil nâest pas facile de nommer lâacte du viol (qui peut se classer dans un vaste rĂ©pertoire de violences sexuelles) ni de le comptabiliser en raison des lacunes persistante..
Représentations des intimités amoureuses dans la France du xxe siÚcle
Cet article aborde la question de la façon dont on peut Ă©crire une histoire de lâintimitĂ©, en se concentrant sur le xxe siĂšcle et en se basant sur de nouvelles sources : les archives autobiographiques (les journaux intimes, les histoires autobiographiques et la correspondance). Comment les individus ont-ils imaginĂ© leurs pratiques amoureuses et quel sens avaient-elles ? Le domaine de lâintimitĂ© reste en retrait pendant la pĂ©riode de lâentre-deux-guerres, il est remis en question entre 1939 et 1965 et se retrouve finalement exposĂ© au grand jour pendant la pĂ©riode de mai 1968 (de 1965 Ă 1975).This article addresses the question as how to write a history of intimacy, focusing on the twentieth century and based on new sources: autobiographical archives (personal diaries, autobiographical stories and correspondence). How did individuals imagine their amorous practices and what meaning did they hold? The realm of intimacy remains subdued during the interwar period, challenged during 1939-1965 and finally brought out into the open during the Mayâ 68 period (1965-1975)
DeconstrucciĂłn del realismo. Paradojas de la metĂĄfora del teatro en "El vano ayer" de Isaac Rosa
Estudiamos un relato que piensa y deconstruye los modos realistas de la novela de la memoria en España, a partir del anĂĄlisis de la metĂĄfora del espectĂĄculo teatral proteiforme y omnipresente en "El vano ayer" de Isaac Rosa, dialogando con el artĂculo de G. Champeau en esta revista. Exploramos las pistas de la categorĂa crĂtica de los "nuevos realismos" con una metĂĄfora que asume un complejo gesto polĂ©mico y renovador en la obra: el vĂnculo entre este "nuevo" realismo y la escritura de la memoria; la renovaciĂłn que emprende "El vano ayer" de la concepciĂłn de la mimesis; y la relaciĂłn con la genealogĂa realista heredada de la historia de la literatura española. La metĂĄfora del teatro serĂĄ a la vez, en su modalidad degradada de la farsa, lo que plasma los fallos del discurso realista actual para contar el pasado, mientras que en su versiĂłn mĂĄs reflexiva, brechtiana, busca exhibir la construcciĂłn del discurso y de los imaginarios sociales
Marie-Carmen Garcia, Amours clandestines. Sociologie de lâextraconjugalitĂ© durable
« Les relations extraconjugales qui durent constituent une Ă©nigme qui dĂ©range Ă la fois les normes conjugales, les normes amoureuses et les normes qui rĂ©gissent la masculinitĂ© et la fĂ©minité » (p. 27). Câest sur cette Ă©nigme que se penche la sociologue Marie-Carmen Garcia, dĂ©sireuse de traiter un sujet peu abordĂ© en sociologie, soit parce quâil reste sous le sceau du secret de la part des intĂ©ressĂ©s, soit par quâil est jugĂ© lĂ©gĂšrement frivole, voire totalement inconvenant par les chercheuses ..
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