Portail HAL du Collège de France
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Philologie de la civilisation japonaise: [résumé des cours et travaux : 2021-2022]
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Oncologie cellulaire et moléculaire: [résumé des cours et travaux : 2021-2022]
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Le Second Bardo appelé Bardo du Moment de la Mort, Instructions Orales sur la Claire-Lumière du Bardo (Bar do ‘od gsal gyi gdams ngag shi kha ma’i bar do bya ba bar do gnyis pa)
No full textAn analysis of the Ganden Phodrang’s state-building process with a focus on its final phase of modernisation
No full textInternational audienceThe Ganden Phodrang, as a state entity and as a bureaucratic administration is often envisaged as a static organisation during its three centuries of existence, from its creation in 1642 until its final demise in 1959. However, despite the general continuity of its political institutions, the Ganden Phodrang state underwent a striking phase of modernisation in its last period of existence, during the period of de facto independence from 1913 to 1950, which has been overlooked for a variety of reasons. Based on Tibetan languages descriptions of the Ganden Phodrang administration on the one hand, and on a social study of the administration (a prosopography of the lay officials of the Ganden Phodrang) on the other hand, the present study posits that the Ganden Phodrang state underwent a striking modernization phase during the period from 1913 to 1950 when compared with previous historical periods. This modernisation is marked mainly by the expansion of the bureaucracy, in terms of number of offices and officials, as well as in terms of an increased specialisation and professionalisation; second, the Ganden Phodrang territorial administration underwent a growing centralisation. A focus on these features allows to better understand the process of state building at work in the largest Tibetan polity of this period
Directional Search for Persistent Gravitational Waves: Results from the First Part of LIGO-Virgo-KAGRA's Fourth Observing Run
No full textInternational audienceThe angular distribution of gravitational-wave power from persistent sources may exhibit anisotropies arising from the large-scale structure of the Universe. This motivates directional searches for astrophysical and cosmological gravitational-wave backgrounds, as well as continuous-wave emitters. We present results of such a search using data from the first observing run through the first portion of the fourth observing run of the LIGO-Virgo-KAGRA Collaborations. We apply gravitational-wave radiometer techniques to generate skymaps and search for both narrowband and broadband persistent gravitational-wave sources. Additionally, we use spherical harmonic decomposition to probe spatially extended sources. No evidence of persistent gravitational-wave signals is found, and we set the most stringent constraints to date on such emissions. For narrowband point sources, our sensitivity estimate to effective strain amplitude lies in the range across all sky and frequency range Hz. For targeted sources -- Scorpius X-1, SN 1987A, the Galactic Center, Terzan 5, and NGC 6397 -- we constrain the strain amplitude with best limits ranging from to . For persistent broadband sources, we constrain the gravitational-wave flux F_{α, \hat{n}}^{95\%, \mathrm{UL}}(25\, \mathrm{Hz}) < (0.008 - 5.5) \times 10^{-8}\, \mathrm{erg\, cm^{-2}\, s^{-1}\, Hz^{-1}}, depending on the sky direction and spectral index . Finally, for extended sources, we place upper limits on the strain angular power spectrum C_\ell^{1/2} < (0.63 - 17) \times 10^{-10} \,\mathrm{sr}^{-1}
Upper Limits on the Isotropic Gravitational-Wave Background from the first part of LIGO, Virgo, and KAGRA's fourth Observing Run
No full textInternational audienceWe present results from the search for an isotropic gravitational-wave background using Advanced LIGO and Advanced Virgo data from O1 through O4a, the first part of the fourth observing run. This background is the accumulated signal from unresolved sources throughout cosmic history and encodes information about the merger history of compact binaries throughout the Universe, as well as exotic physics and potentially primordial processes from the early cosmos. Our cross-correlation analysis reveals no statistically significant background signal, enabling us to constrain several theoretical scenarios. For compact binary coalescences which approximately follow a 2/3 power-law spectrum, we constrain the fractional energy density to (95% cred.), a factor of 1.7 improvement over previous results. Scale-invariant backgrounds are constrained to , representing a 2.1x sensitivity gain. We also place new limits on gravity theories predicting non-standard polarization modes and confirm that terrestrial magnetic noise sources remain below detection threshold. Combining these spectral limits with population models for GWTC-4, the latest gravitational-wave event catalog, we find our constraints remain above predicted merger backgrounds but are approaching detectability. The joint analysis combining the background limits shown here with the GWTC-4 catalog enables improved inference of the binary black hole merger rate evolution across cosmic time. Employing GWTC-4 inference results and standard modeling choices, we estimate that the total background arising from compact binary coalescences is at 90% confidence, where the largest contribution is due to binary black holes only,
Procréations médicalement assistées en islam ainsi que dans le judaïsme et le catholicisme. Genre, filiation, sexualité et religions
No full textInternational audienceAlors qu'on tient pour acquis que les techniques de procréation médicalement assistée auraient séparé la procréation de la sexualité, la sexualité dans ses multiples dimensions, non seulement physique mais également psychique, est loin d'avoir disparu de ces nouvelles manières de procréer. C'est ce que révèlent avec force les interrogations de certaines religions vis-à-vis de ces techniques, notamment l'islam sunnite qui sera mis en perspective avec les autres monothéismes, soit le judaïsme et le catholicisme romain, mais aussi avec l'islam shiite. Nous analyserons également les positions de l'islam à l'égard de la conservation et de l'accueil des embryons, du clonage reproductif, des mères porteuses, de l'avortement thérapeutique, du diagnostic préimplantatoire et de la sélection du sexe de l'enfant. Les questions débattues par les monothéismes à propos des procréations médicalement assistées, qu'il s'agisse des questions de filiation, de sexualité, d'adultère ou d'inceste, se posent plus largement à toutes les sociétés, quel que soit le contexte, religieux ou laïque, notamment lorsque ces techniques impliquent un tiers donneur
