236 research outputs found
Le revenu minimum garanti et les problĂšmes juridiques de sa mise en oeuvre
L'Ă©volution de la protection sociale, au Canada et au QuĂ©bec, en direction d'un revenu minimum garanti se heurte, en l'Ă©tat actuel des choses, Ă de formidables obstacles. Ces obstacles tiennent Ă la fragmentation et Ă complexitĂ© du systĂšme de sĂ©curitĂ© sociale, Ă la souplesse et Ă la mallĂ©abilitĂ© que lui confĂšre le recours Ă quatre techniques diffĂ©rentes de sĂ©curitĂ© sociale, et surtout aux difficultĂ©s d'ordre constitutionnel et politique dĂ©coulant principalement du partage des compĂ©tences lĂ©gislatives. Ce constat s'appuie sur une analyse du cadre juridique actuel de la protection sociale de base. Celle-ci comprend notamment l'assistance sociale, dont le cadre actuel au QuĂ©bec est la Loi sur la sĂ©curitĂ© du revenu. Parmi les principaux problĂšmes juridiques que suscite ou suscitera vraisemblablement cette loi, sont examinĂ©s : l'incidence des droits fondamentaux, celle du RĂ©gime d'assistance publique du Canada, et les exigences de la lĂ©galitĂ© administrative. Sont ensuite briĂšvement analysĂ©es les autres composantes de la protection sociale de base : les prestations de sĂ©curitĂ© de la vieillesse et les prestations familiales. Le texte rappelle ensuite les caractĂ©ristiques des quatre techniques de sĂ©curitĂ© sociale pratiquĂ©es au Canada et au QuĂ©bec : l'assurance sociale, les prestations universelles, l'assistance sociale et la garantie de revenu. Ce rappel, qui vise Ă mettre en relief l'effet de complĂ©mentaritĂ© obtenu par le recours aux quatre techniques, dĂ©bouche sur la critique de leurs inconvĂ©nients respectifs, qui dans aucun cas ne semblent en justifier l'abandon aux yeux du public et des dirigeants politiques. Enfin, le texte revient sur les tentatives de mise au point d'une formule de revenu minimum garanti pendant les annĂ©es 1970. Il conclut de l'Ă©chec de ces tentatives, entreprises pourtant dans un climat politique et Ă©conomique relativement favorable, qu'il n'y a pas lieu d'escompter l'aboutissement prochain de propositions nouvelles dans le mĂȘme sens.Major obstacles currently hinder the development of a guaranteed minimum income (GMI) out of the existing Canadian and Quebec social security system. Obstacles flow from the system's fragmentation and complexity ; others stem from the very advantages of the system, namely the flexibility and comprehensiveness offered by the combination of four different techniques of social security : above all, obstacles to any move towards GMI are built in the constitutional and political constraints of federalism. This point is grounded on an analysis of the existing legal framework of basic-level social security in Canada. This mainly involves social assistance schemes in the provinces. The Quebec Income Security Act of 1988 is a fairly typical example of these. The paper surveys some of the major actual or foreseeable legal issues arising out ofthat scheme : its relationship to fundamental rights, to the Canada Assistance Plan and to the requirements of the rule of law in administrative action. Other components of basic-level social security â Old Age Security and family benefits â are then briefly outlined. The paper then proceeds to discuss the specific features of each of the four techniques implemented in the Canada and Quebec social security system : social insurance, universal benefits, social assistance and guaranteed income. The discussion brings out the complementary relationship between the four techniques, as well as their respective drawbacks and concludes that in the eyes of the general public and political leaders, the later do not justify abandoning any of the four. Finally, the paper goes back over the intergovernmental negotiations on GMI during the 1970s. The unfruitfulness of these negotiations, in spite of an initially favourable political and economic climate, suggests that current conditions are unlikely to favour early progress towards a GMI scheme
A generic frequency dependence for the atmospheric tidal torque of terrestrial planets
Thermal atmospheric tides have a strong impact on the rotation of terrestrial
planets. They can lock these planets into an asynchronous rotation state of
equilibrium. We aim at characterizing the dependence of the tidal torque
resulting from the semidiurnal thermal tide on the tidal frequency, the planet
orbital radius, and the atmospheric surface pressure. The tidal torque is
computed from full 3D simulations of the atmospheric climate and mean flows
using a generic version of the LMDZ general circulation model (GCM) in the case
of a nitrogen-dominated atmosphere. Numerical results are discussed with the
help of an updated linear analytical framework. Power scaling laws governing
the evolution of the torque with the planet orbital radius and surface pressure
are derived. The tidal torque exhibits i) a thermal peak in the vicinity of
synchronization, ii) a resonant peak associated with the excitation of the Lamb
mode in the high frequency range, and iii) well defined frequency slopes
outside these resonances. These features are well explained by our linear
theory. Whatever the star-planet distance and surface pressure, the torque
frequency spectrum -- when rescaled with the relevant power laws -- always
presents the same behaviour. This allows us to provide a single and easily
usable empirical formula describing the atmospheric tidal torque over the whole
parameter space. With such a formula, the effect of the atmospheric tidal
torque can be implemented in evolutionary models of the rotational dynamics of
a planet in a computationally efficient, and yet relatively accurate way.Comment: Accepted for publication in Astronomy & Astrophysics, 23 pages, 9
figure
Strategies as Resource Terms, and Their Categorical Semantics
As shown by Tsukada and Ong, simply-typed, normal and η-long resource terms correspond to plays in Hyland-Ong games, quotiented by MelliÚs' homotopy equivalence. Though inspiring, their proof is indirect, relying on the injectivity of the relational model {w.r.t.} both sides of the correspondence - in particular, the dynamics of the resource calculus is taken into account only via the compatibility of the relational model with the composition of normal terms defined by normalization. In the present paper, we revisit and extend these results. Our first contribution is to restate the correspondence by considering causal structures we call augmentations, which are canonical representatives of Hyland-Ong plays up to homotopy. This allows us to give a direct and explicit account of the connection with normal resource terms. As a second contribution, we extend this account to the reduction of resource terms: building on a notion of strategies as weighted sums of augmentations, we provide a denotational model of the resource calculus, invariant under reduction. A key step - and our third contribution - is a categorical model we call a resource category, which is to the resource calculus what differential categories are to the differential λ-calculus
Cosmology with the Laser Interferometer Space Antenna
This work is partly supported by: A.G. Leventis Foundation; Academy of Finland Grants 328958 and 345070; Alexander S. Onassis Foundation, Scholarship ID: FZO 059-1/2018-2019; Amaldi Research Center funded by the MIUR program âDipartimento di Eccellenzaâ (CUP: B81I18001170001); ASI Grants No. 2016-24-H.0 and No. 2016-24-H.1-2018; AtracciĂłn de Talento Grant 2019-T1/TIC-15784; AtracciĂłn de Talento contract no. 2019-T1/TIC-13177 granted by the Comunidad de Madrid; Ayuda âBeatriz Galindo Seniorâ by the Spanish âMinisterio de Universidadesâ, Grant BG20/00228; Basque Government Grant (IT-979-16); Belgian Francqui Foundation; Centre national dâEtudes spatiales; Ben Gurion University Kreitman Fellowship, and the Israel Academy of Sciences and Humanities (IASH) & Council for Higher Education (CHE) Excellence Fellowship Program for International Postdoctoral Researchers; Centro de Excelencia Severo Ochoa Program SEV-2016-0597; CERCA program of the Generalitat de Catalunya; Cluster of Excellence âPrecision Physics, Fundamental Interactions, and Structure of Matterâ (PRISMA+ EXC 2118/1); Comunidad de Madrid, Contrato de AtracciĂłn de Talento 2017-T1/TIC-5520; Czech Science Foundation GAÄR, Grant No. 21-16583M; Delta ITP consortium; Department of Energy under Grant No. DE-SC0008541, DE-SC0009919 and DE-SC0019195; Deutsche Forschungsgemeinschaft (DFG), Project ID 438947057; Deutsche Forschungsgemeinschaft under Germanyâs Excellence Strategy - EXC 2121 Quantum Universe - 390833306; European Structural and Investment Funds and the Czech Ministry of Education, Youth and Sports (Project CoGraDS - CZ.02.1.01/0.0/0.0/15 003/0000437); European Unionâs H2020 ERC Consolidator Grant âGRavity from Astrophysical to Microscopic Scalesâ (Grant No. GRAMS-815673); European Unionâs H2020 ERC, Starting Grant Agreement No. DarkGRA-757480; European Unionâs Horizon 2020 programme under the Marie Sklodowska-Curie Grant Agreement 860881 (ITN HIDDeN); European Unionâs Horizon 2020 Research and Innovation Programme Grant No. 796961, âAxiBAUâ (K.S.); European Unionâs Horizon 2020 Research Council grant 724659 MassiveCosmo ERC-2016-COG; FCT through national funds (PTDC/FIS-PAR/31938/2017) and through project âBEYLA â BEYond LAmbdaâ with Ref. Number PTDC/FIS-AST/0054/2021; FEDER-Fundo Europeu de Desenvolvimento Regional through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI-01-0145-FEDER-031938) and research Grants UIDB/04434/2020 and UIDP/04434/2020; Fondation CFM pour la Recherche in France; Foundation for Education and European Culture in Greece; French ANR project MMUniverse (ANR-19-CE31-0020); FRIA Grant No.1.E.070.19F of the Belgian Fund for Research, F.R.S.-FNRS Fundação para a CiĂȘncia e a Tecnologia (FCT) through Contract No. DL 57/2016/CP1364/CT0001; Fundação para a CiĂȘncia e a Tecnologia (FCT) through Grants UIDB/04434/2020, UIDP/04434/2020, PTDC/FIS-OUT/29048/2017, CERN/FIS-PAR/0037/2019 and âCosmoTests â Cosmological tests of gravity theories beyond General Relativityâ CEECIND/00017/2018; Generalitat Valenciana Grant PROMETEO/2021/083; Grant No. 758792, project GEODESI; Government of Canada through the Department of Innovation, Science and Economic Development and Province of Ontario through the Ministry of Colleges and Universities; Grants-in-Aid for JSPS Overseas Research Fellow (No. 201960698); I+D Grant PID2020-118159GB-C41 of the Spanish Ministry of Science and Innovation; INFN iniziativa specifica TEONGRAV; Israel Science Foundation (Grant No. 2562/20); Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Nos. 20H01899 and 20H05853; IFT Centro de Excelencia Severo Ochoa Grant SEV-2; Kavli Foundation and its founder Fred Kavli; Minerva Foundation; Ministerio de Ciencia e Innovacion Grant PID2020-113644GB-I00; NASA Grant 80NSSC19K0318; NASA Hubble Fellowship grants No. HST-HF2-51452.001-A awarded by the Space Telescope Science Institute with NASA contract NAS5-26555; Netherlands Organisation for Science and Research (NWO) Grant Number 680-91-119; new faculty seed start-up grant of the Indian Institute of Science, Bangalore, the Core Research Grant CRG/2018/002200 of the Science and Engineering; NSF Grants PHY-1820675, PHY-2006645 and PHY-2011997; Polish National Science Center Grant 2018/31/D/ST2/02048; Polish National Agency for Academic Exchange within the Polish Returns Programme under Agreement PPN/PPO/2020/1/00013/U/00001; PrĂł-Reitoria de Pesquisa of Universidade Federal de Minas Gerais (UFMG) under Grant No. 28359; RamĂłn y Cajal Fellowship contract RYC-2017-23493; Research Project PGC2018-094773-B-C32 [MINECO-FEDER]; Research Project PGC2018-094773-B-C32 [MINECO-FEDER]; ROMFORSK Grant Project. No. 302640; Royal Society Grant URF/R1/180009 and ERC StG 949572: SHADE; Shota Rustaveli National Science Foundation (SRNSF) of Georgia (Grant FR/18-1462); Simons Foundation/SFARI 560536; SNSF Ambizione grant; SNSF professorship Grant (No. 170547); Spanish MINECOâs âCentro de Excelencia Severo Ochoaâ Programme Grants SEV-2016-0597 and PID2019-110058GB-C22; Spanish Ministry MCIU/AEI/FEDER Grant (PGC2018-094626-B-C21); Spanish Ministry of Science and Innovation (PID2020-115845GB-I00/AEI/10.13039/501100011033); Spanish Proyectos de I+D via Grant PGC2018-096646-A-I00; STFC Consolidated Grant ST/T000732/1; STFC Consolidated Grants ST/P000762/1 and ST/T000791/1; STFC Grant ST/S000550/1; STFC Grant ST/T000813/1; STFC Grants ST/P000762/1 and ST/T000791/1; STFC under the research Grant ST/P000258/1; Swiss National Science Foundation (SNSF), project The Non-Gaussian Universe and Cosmological Symmetries, Project Number: 200020-178787; Swiss National Science Foundation Professorship Grants No. 170547 and No. 191957; SwissMap National Center for Competence in Research; âThe Dark Universe: A Synergic Multi-messenger Approachâ Number 2017X7X85K under the MIUR program PRIN 2017; UK Space Agency; UKSA Flagship Project, Euclid.The Laser Interferometer Space Antenna (LISA) has two scientific objectives of cosmological focus: to probe the expansion rate of the universe, and to understand stochastic gravitational-wave backgrounds and their implications for early universe and particle physics, from the MeV to the Planck scale. However, the range of potential cosmological applications of gravitational-wave observations extends well beyond these two objectives. This publication presents a summary of the state of the art in LISA cosmology, theory and methods, and identifies new opportunities to use gravitational-wave observations by LISA to probe the universe.AtracciĂłn de Talento
2019-T1/TIC-13177Centro de Excelencia Severo Ochoa Program
EXC 2118/1, SEV-2016-0597Contrato de AtracciĂłn de Talento
2017-T1/TIC-5520European Unionâs H2020 ERC
GRAMS-815673European Unionâs Horizon 2020 Research Council
724659 MassiveCosmo ERC-2016-COGEuropean Unionâs Horizon 2020 programme
860881, ITN HIDDeNIFT Centro de Excelencia Severo OchoaSpanish Ministry MCIU
PGC2018-094626-B-C21, PGC2018-096646-A-I00, PID2020-115845GB-I00/AEI/10.13039/501100011033Horizon 2020 Framework Programme
796961 H2020Comunidad de MadridEusko Jaurlaritza
IT-979-16Ministerio de EconomĂa y Competitividad
302640 MINECOGeneralitat Valenciana
758792, PROMETEO/2021/083 GVAMinisterio de Ciencia e InnovaciĂłn
PID2020-113644GB-I00 MICINNMinisterio de Universidades
BG20/00228 MIUEuropean Unionâs
H2020 ERC, DarkGRA-75748
Cosmic string bursts in LISA
Cosmic string cusps are sources of short-lived, linearly polarised
gravitational wave bursts which can be searched for in gravitational wave
detectors. We assess the capability of LISA to detect these bursts using the
latest LISA configuration and operational assumptions. For such short bursts,
we verify that LISA can be considered as ``frozen", namely that one can neglect
LISA's orbital motion. We consider two models for the network of cosmic string
loops, and estimate that LISA should be able to detect 1-3 bursts per year
assuming a string tension and detection
threshold . Non-detection of these bursts would constrain the
string tension to for both models.Comment: 6 page
Transitions - Note 2
Note complÚte ; Résumé ; Capsule 2 : L'accÚs inégal des influence des « EPG » à l'éducation postsecondair
Thermal tides in neutrally stratified atmospheres: Revisiting the Earth's Precambrian rotational equilibrium
Rotational dynamics of the Earth, over geological timescales, have profoundly
affected local and global climatic evolution, probably contributing to the
evolution of life. To better retrieve the Earth's rotational history, and
motivated by the published hypothesis of a stabilized length of day during the
Precambrian, we examine the effect of thermal tides on the evolution of
planetary rotational motion. The hypothesized scenario is contingent upon
encountering a resonance in atmospheric Lamb waves, whereby an amplified
thermotidal torque cancels the opposing torque of the oceans and solid
interior, driving the Earth into a rotational equilibrium. With this scenario
in mind, we construct an ab initio model of thermal tides on rocky planets
describing a neutrally stratified atmosphere. The model takes into account
dissipative processes with Newtonian cooling and diffusive processes in the
planetary boundary layer. We retrieve from this model a closed-form solution
for the frequency-dependent tidal torque which captures the main spectral
features previously computed using 3D general circulation models. In
particular, under longwave heating, diffusive processes near the surface and
the delayed thermal response of the ground prove to be responsible for
attenuating, and possibly annihilating, the accelerating effect of the
thermotidal torque at the resonance. When applied to the Earth, our model
prediction suggests the occurrence of the Lamb resonance in the Phanerozoic,
but with an amplitude that is insufficient for the rotational equilibrium.
Interestingly, though our study was motivated by the Earth's history, the
generic tidal solution can be straightforwardly and efficiently applied in
exoplanetary settings.Comment: 20 pages (+14 for appendices), 6 figure
Can one hear supercontinents in the tides of ocean planets?
Recent observations and theoretical progress made about the history of the
Earth-Moon system suggest that tidal dissipation in oceans primarily drives the
long term evolution of orbital systems hosting ocean planets. Particularly,
they emphasise the key role played by the geometry of land-ocean distributions
in this mechanism. However, the complex way continents affect oceanic tides
still remains to be elucidated. In the present study, we investigate the impact
of a single supercontinent on the tidal response of an ocean planet and the
induced tidally dissipated energy. The adopted approach is based on the linear
tidal theory. By simplifying the continent to a spherical cap of given angular
radius and position on the globe, we proceed to a harmonic analysis of the
whole planet's tidal response including the coupling with the solid part due to
ocean loading and self-attraction variations. In this framework, tidal flows
are formulated analytically in terms of explicitly defined oceanic eigenmodes,
as well as the resulting tidal Love numbers, dissipated power, and torque. The
analysis highlights the symmetry breaking effect of the continent, which makes
the dependence of tidal quantities on the tidal frequency become highly
irregular. The metric introduced to quantify this continentality effect reveals
abrupt transitions between polar and non-polar configurations, and between
small-sized and medium-sized continents. Additionally, it predicts that a
continent similar to South America or smaller (30{\deg}-angular radius) does
not alter qualitatively the tidal response of a global ocean whatever its
position on the planet.Comment: 35 pages, 13 figures, 5 tables. Accepted for publication in Astronomy
& Astrophysic
Transitions Note 2 : Les étudiants de premiÚre génération : un concept prometteur? /
Note complÚte ; Résumé ; Capsule ; Full text
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