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Vivian Poulin

Bio: Vivian Poulin is an academic researcher from University of Montpellier. The author has contributed to research in topics: Cosmic microwave background & Dark matter. The author has an hindex of 38, co-authored 92 publications receiving 4591 citations. Previous affiliations of Vivian Poulin include RWTH Aachen University & Laboratoire d'Annecy-le-Vieux de physique des particules.

Papers published on a yearly basis

Papers
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Journal ArticleDOI
TL;DR: In this article, a Markov Chain Monte-Carlo search of the parameter space for the EDE parameters, in conjunction with the standard cosmological parameters, identifies regions in which H = 0.
Abstract: Early dark energy (EDE) that behaves like a cosmological constant at early times (redshifts z≳3000) and then dilutes away like radiation or faster at later times can solve the Hubble tension. In these models, the sound horizon at decoupling is reduced resulting in a larger value of the Hubble parameter H_{0} inferred from the cosmic microwave background (CMB). We consider two physical models for this EDE, one involving an oscillating scalar field and another a slowly rolling field. We perform a detailed calculation of the evolution of perturbations in these models. A Markov Chain Monte Carlo search of the parameter space for the EDE parameters, in conjunction with the standard cosmological parameters, identifies regions in which H_{0} inferred from Planck CMB data agrees with the SH0ES local measurement. In these cosmologies, current baryon acoustic oscillation and supernova data are described as successfully as in the cold dark matter model with a cosmological constant, while the fit to Planck data is slightly improved. Future CMB and large-scale-structure surveys will further probe this scenario.

657 citations

Journal ArticleDOI
TL;DR: In this paper , the authors focus on the 5.0σ tension between the Planck CMB estimate of the Hubble constant H0 and the SH0ES collaboration measurements and discuss the importance of trying to fit a full array of data with a single model.

335 citations

Journal ArticleDOI
Eleonora Di Valentino1, Luis A. Anchordoqui2, Özgür Akarsu3, Yacine Ali-Haïmoud4, Luca Amendola5, Nikki Arendse6, Marika Asgari7, Mario Ballardini8, Spyros Basilakos9, Elia S. Battistelli10, Micol Benetti11, Simon Birrer12, François R. Bouchet13, Marco Bruni14, Erminia Calabrese15, David Camarena16, Salvatore Capozziello11, Angela Chen17, Jens Chluba1, Anton Chudaykin, Eoin Ó Colgáin18, Francis-Yan Cyr-Racine19, Paolo de Bernardis10, Javier de Cruz Pérez20, Jacques Delabrouille21, Jo Dunkley22, Celia Escamilla-Rivera23, Agnès Ferté24, Fabio Finelli25, Wendy L. Freedman26, Noemi Frusciante, Elena Giusarma27, Adrià Gómez-Valent5, Julien Guy28, Will Handley29, Ian Harrison1, Luke Hart1, Alan Heavens30, Hendrik Hildebrandt31, Daniel E. Holz26, Dragan Huterer17, Mikhail M. Ivanov4, Shahab Joudaki32, Shahab Joudaki33, Marc Kamionkowski34, Tanvi Karwal35, Lloyd Knox36, Suresh Kumar37, Luca Lamagna10, Julien Lesgourgues38, Matteo Lucca39, Valerio Marra16, Silvia Masi10, Sabino Matarrese40, Arindam Mazumdar41, Alessandro Melchiorri10, Olga Mena42, Laura Mersini-Houghton43, Vivian Miranda44, Cristian Moreno-Pulido20, David F. Mota45, J. Muir12, Ankan Mukherjee46, Florian Niedermann47, Alessio Notari20, Rafael C. Nunes48, Francesco Pace1, Andronikos Paliathanasis, Antonella Palmese49, Supriya Pan50, Daniela Paoletti25, Valeria Pettorino51, F. Piacentini10, Vivian Poulin52, Marco Raveri35, Adam G. Riess34, Vincenzo Salzano53, Emmanuel N. Saridakis, Anjan A. Sen46, Arman Shafieloo54, Anowar J. Shajib55, Joseph Silk56, Joseph Silk34, Alessandra Silvestri57, Martin S. Sloth47, Tristan L. Smith58, Joan Solà Peracaula20, Carsten van de Bruck59, Licia Verde20, Luca Visinelli60, Benjamin D. Wandelt56, Deng Wang, Jian-Min Wang, Anil Kumar Yadav61, Weiqiang Yang62 
University of Manchester1, City University of New York2, Istanbul Technical University3, New York University4, Heidelberg University5, Niels Bohr Institute6, University of Edinburgh7, University of Bologna8, Academy of Athens9, Sapienza University of Rome10, University of Naples Federico II11, Stanford University12, Institut d'Astrophysique de Paris13, University of Portsmouth14, Cardiff University15, Universidade Federal do Espírito Santo16, University of Michigan17, Asia Pacific Center for Theoretical Physics18, University of New Mexico19, University of Barcelona20, University of St. Thomas (Minnesota)21, Princeton University22, National Autonomous University of Mexico23, California Institute of Technology24, INAF25, University of Chicago26, Michigan Technological University27, Lawrence Berkeley National Laboratory28, University of Cambridge29, Imperial College London30, Ruhr University Bochum31, University of Waterloo32, University of Oxford33, Johns Hopkins University34, University of Pennsylvania35, University of California, Davis36, Birla Institute of Technology and Science37, RWTH Aachen University38, Université libre de Bruxelles39, University of Padua40, Indian Institute of Technology Kharagpur41, Spanish National Research Council42, University of North Carolina at Chapel Hill43, University of Arizona44, University of Oslo45, Jamia Millia Islamia46, University of Southern Denmark47, National Institute for Space Research48, Fermilab49, Presidency University, Kolkata50, Université Paris-Saclay51, University of Montpellier52, University of Szczecin53, Korea Astronomy and Space Science Institute54, University of California, Los Angeles55, University of Paris56, Leiden University57, Swarthmore College58, University of Sheffield59, University of Amsterdam60, United College, Winnipeg61, Liaoning Normal University62
TL;DR: In this article, the authors focus on the 4.4σ tension between the Planck estimate of the Hubble constant H0 and the SH0ES collaboration measurements and discuss how the next decade's experiments will be crucial.

322 citations

Journal ArticleDOI
TL;DR: In this paper, the authors derived constraints on the fraction of DM in primordial black holes (PBH) and provided that disks form early on, even under conservative assumptions for accretion, these constraints exclude a monochromatic distribution of PBH with masses above
Abstract: Stellar-mass primordial black holes (PBH) have been recently reconsidered as a dark matter (DM) candidate after the aLIGO discovery of several binary black hole (BH) mergers with masses of tens of ${M}_{\ensuremath{\bigodot}}$. Matter accretion on such massive objects leads to the emission of high-energy photons, capable of altering the ionization and thermal history of the universe. This, in turn, affects the statistical properties of the cosmic microwave background (CMB) anisotropies. Previous analyses have assumed spherical accretion. We argue that this approximation likely breaks down and that an accretion disk should form in the dark ages. Using the most up-to-date tools to compute the energy deposition in the medium, we derive constraints on the fraction of DM in PBH. Provided that disks form early on, even under conservative assumptions for accretion, these constraints exclude a monochromatic distribution of PBH with masses above $\ensuremath{\sim}2\text{ }\text{ }{M}_{\ensuremath{\bigodot}}$ as the dominant form of DM. The bound on the median PBH mass gets more stringent if a broad, log-normal mass function is considered. A deepened understanding of nonlinear clustering properties and BH accretion disk physics would permit an improved treatment and possibly lead to more stringent constraints.

270 citations

Journal ArticleDOI
TL;DR: In this article, a cosmological model in which a fraction fdcdm of the Dark Matter (DM) is allowed to decay in an invisible relativistic component is considered, and the resulting constraints on both the decay width (or inverse lifetime) ΓdCDm and fdcfm from purely gravitational arguments are derived.
Abstract: We consider a cosmological model in which a fraction fdcdm of the Dark Matter (DM) is allowed to decay in an invisible relativistic component, and compute the resulting constraints on both the decay width (or inverse lifetime) Γdcdm and fdcdm from purely gravitational arguments. We report a full derivation of the Boltzmann hierarchy, correcting a mistake in previous literature, and compute the impact of the decay—as a function of the lifetime—on the CMB and matter power spectra. From CMB only, we obtain that no more than 3.8% of the DM could have decayed in the time between recombination and today (all bounds quoted at 95% CL). We also comment on the important application of this bound to the case where primordial black holes constitute DM, a scenario notoriously difficult to constrain. For lifetimes longer than the age of the Universe, the bounds can be cast as fdcdmΓdcdm < 6.3×10−3 Gyr−1. For the first time, we also checked that degeneracies with massive neutrinos are broken when information from the large scale structure is used. Even secondary effects like CMB lensing suffice to this purpose. Decaying DM models have been invoked to solve a possible tension between low redshift astronomical measurements of σ8 and Ωm and the ones inferred by Planck. We reassess this claim finding that with the most recent BAO, HST and σ8 data extracted from the CFHT survey, the tension is only slightly reduced despite the two additional free parameters. Nonetheless, the existing tension explains why the bound on fdcdmΓdcdm loosens to fdcdmΓdcdm < 15.9×10−3 Gyr−1 when including such additional data. The bound however improves to fdcdmΓdcdm < 5.9 ×10−3 Gyr−1 if only data consistent with the CMB are included. This highlights the importance of establishing whether the tension is due to real physical effects or unaccounted systematics, for settling the reach of achievable constraints on decaying DM.

212 citations


Cited by
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Journal ArticleDOI
Peter A. R. Ade1, Nabila Aghanim2, Monique Arnaud3, M. Ashdown4  +334 moreInstitutions (82)
TL;DR: In this article, the authors present a cosmological analysis based on full-mission Planck observations of temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation.
Abstract: This paper presents cosmological results based on full-mission Planck observations of temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation. Our results are in very good agreement with the 2013 analysis of the Planck nominal-mission temperature data, but with increased precision. The temperature and polarization power spectra are consistent with the standard spatially-flat 6-parameter ΛCDM cosmology with a power-law spectrum of adiabatic scalar perturbations (denoted “base ΛCDM” in this paper). From the Planck temperature data combined with Planck lensing, for this cosmology we find a Hubble constant, H0 = (67.8 ± 0.9) km s-1Mpc-1, a matter density parameter Ωm = 0.308 ± 0.012, and a tilted scalar spectral index with ns = 0.968 ± 0.006, consistent with the 2013 analysis. Note that in this abstract we quote 68% confidence limits on measured parameters and 95% upper limits on other parameters. We present the first results of polarization measurements with the Low Frequency Instrument at large angular scales. Combined with the Planck temperature and lensing data, these measurements give a reionization optical depth of τ = 0.066 ± 0.016, corresponding to a reionization redshift of . These results are consistent with those from WMAP polarization measurements cleaned for dust emission using 353-GHz polarization maps from the High Frequency Instrument. We find no evidence for any departure from base ΛCDM in the neutrino sector of the theory; for example, combining Planck observations with other astrophysical data we find Neff = 3.15 ± 0.23 for the effective number of relativistic degrees of freedom, consistent with the value Neff = 3.046 of the Standard Model of particle physics. The sum of neutrino masses is constrained to ∑ mν < 0.23 eV. The spatial curvature of our Universe is found to be very close to zero, with | ΩK | < 0.005. Adding a tensor component as a single-parameter extension to base ΛCDM we find an upper limit on the tensor-to-scalar ratio of r0.002< 0.11, consistent with the Planck 2013 results and consistent with the B-mode polarization constraints from a joint analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP B-mode data to our analysis leads to a tighter constraint of r0.002 < 0.09 and disfavours inflationarymodels with a V(φ) ∝ φ2 potential. The addition of Planck polarization data leads to strong constraints on deviations from a purely adiabatic spectrum of fluctuations. We find no evidence for any contribution from isocurvature perturbations or from cosmic defects. Combining Planck data with other astrophysical data, including Type Ia supernovae, the equation of state of dark energy is constrained to w = −1.006 ± 0.045, consistent with the expected value for a cosmological constant. The standard big bang nucleosynthesis predictions for the helium and deuterium abundances for the best-fit Planck base ΛCDM cosmology are in excellent agreement with observations. We also constraints on annihilating dark matter and on possible deviations from the standard recombination history. In neither case do we find no evidence for new physics. The Planck results for base ΛCDM are in good agreement with baryon acoustic oscillation data and with the JLA sample of Type Ia supernovae. However, as in the 2013 analysis, the amplitude of the fluctuation spectrum is found to be higher than inferred from some analyses of rich cluster counts and weak gravitational lensing. We show that these tensions cannot easily be resolved with simple modifications of the base ΛCDM cosmology. Apart from these tensions, the base ΛCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets.

10,728 citations

Journal ArticleDOI
01 Apr 1988-Nature
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

9,929 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present results based on full-mission Planck observations of temperature and polarization anisotropies of the CMB, which are consistent with the six-parameter inflationary LCDM cosmology.
Abstract: We present results based on full-mission Planck observations of temperature and polarization anisotropies of the CMB. These data are consistent with the six-parameter inflationary LCDM cosmology. From the Planck temperature and lensing data, for this cosmology we find a Hubble constant, H0= (67.8 +/- 0.9) km/s/Mpc, a matter density parameter Omega_m = 0.308 +/- 0.012 and a scalar spectral index with n_s = 0.968 +/- 0.006. (We quote 68% errors on measured parameters and 95% limits on other parameters.) Combined with Planck temperature and lensing data, Planck LFI polarization measurements lead to a reionization optical depth of tau = 0.066 +/- 0.016. Combining Planck with other astrophysical data we find N_ eff = 3.15 +/- 0.23 for the effective number of relativistic degrees of freedom and the sum of neutrino masses is constrained to < 0.23 eV. Spatial curvature is found to be |Omega_K| < 0.005. For LCDM we find a limit on the tensor-to-scalar ratio of r <0.11 consistent with the B-mode constraints from an analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP data leads to a tighter constraint of r < 0.09. We find no evidence for isocurvature perturbations or cosmic defects. The equation of state of dark energy is constrained to w = -1.006 +/- 0.045. Standard big bang nucleosynthesis predictions for the Planck LCDM cosmology are in excellent agreement with observations. We investigate annihilating dark matter and deviations from standard recombination, finding no evidence for new physics. The Planck results for base LCDM are in agreement with BAO data and with the JLA SNe sample. However the amplitude of the fluctuations is found to be higher than inferred from rich cluster counts and weak gravitational lensing. Apart from these tensions, the base LCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets.

9,745 citations

Journal ArticleDOI
Nabila Aghanim1, Yashar Akrami2, Yashar Akrami3, Yashar Akrami4  +229 moreInstitutions (70)
TL;DR: In this article, the authors present cosmological parameter results from the full-mission Planck measurements of the cosmic microwave background (CMB) anisotropies, combining information from the temperature and polarization maps and the lensing reconstruction.
Abstract: We present cosmological parameter results from the final full-mission Planck measurements of the cosmic microwave background (CMB) anisotropies, combining information from the temperature and polarization maps and the lensing reconstruction Compared to the 2015 results, improved measurements of large-scale polarization allow the reionization optical depth to be measured with higher precision, leading to significant gains in the precision of other correlated parameters Improved modelling of the small-scale polarization leads to more robust constraints on manyparameters,withresidualmodellinguncertaintiesestimatedtoaffectthemonlyatthe05σlevelWefindgoodconsistencywiththestandard spatially-flat6-parameter ΛCDMcosmologyhavingapower-lawspectrumofadiabaticscalarperturbations(denoted“base ΛCDM”inthispaper), from polarization, temperature, and lensing, separately and in combination A combined analysis gives dark matter density Ωch2 = 0120±0001, baryon density Ωbh2 = 00224±00001, scalar spectral index ns = 0965±0004, and optical depth τ = 0054±0007 (in this abstract we quote 68% confidence regions on measured parameters and 95% on upper limits) The angular acoustic scale is measured to 003% precision, with 100θ∗ = 10411±00003Theseresultsareonlyweaklydependentonthecosmologicalmodelandremainstable,withsomewhatincreasederrors, in many commonly considered extensions Assuming the base-ΛCDM cosmology, the inferred (model-dependent) late-Universe parameters are: HubbleconstantH0 = (674±05)kms−1Mpc−1;matterdensityparameterΩm = 0315±0007;andmatterfluctuationamplitudeσ8 = 0811±0006 We find no compelling evidence for extensions to the base-ΛCDM model Combining with baryon acoustic oscillation (BAO) measurements (and consideringsingle-parameterextensions)weconstraintheeffectiveextrarelativisticdegreesoffreedomtobe Neff = 299±017,inagreementwith the Standard Model prediction Neff = 3046, and find that the neutrino mass is tightly constrained toPmν < 012 eV The CMB spectra continue to prefer higher lensing amplitudesthan predicted in base ΛCDM at over 2σ, which pulls some parameters that affect thelensing amplitude away from the ΛCDM model; however, this is not supported by the lensing reconstruction or (in models that also change the background geometry) BAOdataThejointconstraintwithBAOmeasurementsonspatialcurvatureisconsistentwithaflatuniverse, ΩK = 0001±0002Alsocombining with Type Ia supernovae (SNe), the dark-energy equation of state parameter is measured to be w0 = −103±003, consistent with a cosmological constant We find no evidence for deviations from a purely power-law primordial spectrum, and combining with data from BAO, BICEP2, and Keck Array data, we place a limit on the tensor-to-scalar ratio r0002 < 006 Standard big-bang nucleosynthesis predictions for the helium and deuterium abundances for the base-ΛCDM cosmology are in excellent agreement with observations The Planck base-ΛCDM results are in good agreement with BAO, SNe, and some galaxy lensing observations, but in slight tension with the Dark Energy Survey’s combined-probe results including galaxy clustering (which prefers lower fluctuation amplitudes or matter density parameters), and in significant, 36σ, tension with local measurements of the Hubble constant (which prefer a higher value) Simple model extensions that can partially resolve these tensions are not favoured by the Planck data

4,688 citations

Journal ArticleDOI
Peter A. R. Ade, Nabila Aghanim, Monique Arnaud, Frederico Arroja, M. Ashdown, J. Aumont, Carlo Baccigalupi, Mario Ballardini, A. J. Banday, R. B. Barreiro, Nicola Bartolo, E. Battaner, K. Benabed, Alain Benoit, A. Benoit-Lévy, J.-P. Bernard, Marco Bersanelli, P. Bielewicz, J. J. Bock, Anna Bonaldi, Laura Bonavera, J. R. Bond, Julian Borrill, François R. Bouchet, F. Boulanger, M. Bucher, Carlo Burigana, R. C. Butler, Erminia Calabrese, Jean-François Cardoso, A. Catalano, Anthony Challinor, A. Chamballu, R.-R. Chary, H. C. Chiang, P. R. Christensen, Sarah E. Church, David L. Clements, S. Colombi, L. P. L. Colombo, C. Combet, D. Contreras, F. Couchot, A. Coulais, B. P. Crill, A. Curto, F. Cuttaia, Luigi Danese, R. D. Davies, R. J. Davis, P. de Bernardis, A. de Rosa, G. de Zotti, Jacques Delabrouille, F.-X. Désert, Jose M. Diego, H. Dole, S. Donzelli, Olivier Doré, Marian Douspis, A. Ducout, X. Dupac, George Efstathiou, F. Elsner, Torsten A. Ensslin, H. K. Eriksen, James R. Fergusson, Fabio Finelli, Olivier Forni, M. Frailis, Aurelien A. Fraisse, E. Franceschi, A. Frejsel, Andrei V. Frolov, S. Galeotta, Silvia Galli, K. Ganga, C. Gauthier, M. Giard, Y. Giraud-Héraud, E. Gjerløw, J. González-Nuevo, Krzysztof M. Gorski, Serge Gratton, A. Gregorio, Alessandro Gruppuso, Jon E. Gudmundsson, Jan Hamann, Will Handley, F. K. Hansen, Duncan Hanson, D. L. Harrison, Sophie Henrot-Versille, C. Hernández-Monteagudo, D. Herranz, S. R. Hildebrandt, E. Hivon, Michael P. Hobson, W. A. Holmes 
TL;DR: In this article, the authors report on the implications for cosmic inflation of the 2018 Release of the Planck CMB anisotropy measurements, which are fully consistent with the two previous Planck cosmological releases, but have smaller uncertainties thanks to improvements in the characterization of polarization at low and high multipoles.
Abstract: We report on the implications for cosmic inflation of the 2018 Release of the Planck CMB anisotropy measurements. The results are fully consistent with the two previous Planck cosmological releases, but have smaller uncertainties thanks to improvements in the characterization of polarization at low and high multipoles. Planck temperature, polarization, and lensing data determine the spectral index of scalar perturbations to be $n_\mathrm{s}=0.9649\pm 0.0042$ at 68% CL and show no evidence for a scale dependence of $n_\mathrm{s}.$ Spatial flatness is confirmed at a precision of 0.4% at 95% CL with the combination with BAO data. The Planck 95% CL upper limit on the tensor-to-scalar ratio, $r_{0.002}<0.10$, is further tightened by combining with the BICEP2/Keck Array BK15 data to obtain $r_{0.002}<0.056$. In the framework of single-field inflationary models with Einstein gravity, these results imply that: (a) slow-roll models with a concave potential, $V" (\phi) < 0,$ are increasingly favoured by the data; and (b) two different methods for reconstructing the inflaton potential find no evidence for dynamics beyond slow roll. Non-parametric reconstructions of the primordial power spectrum consistently confirm a pure power law. A complementary analysis also finds no evidence for theoretically motivated parameterized features in the Planck power spectrum, a result further strengthened for certain oscillatory models by a new combined analysis that includes Planck bispectrum data. The new Planck polarization data provide a stringent test of the adiabaticity of the initial conditions. The polarization data also provide improved constraints on inflationary models that predict a small statistically anisotropic quadrupolar modulation of the primordial fluctuations. However, the polarization data do not confirm physical models for a scale-dependent dipolar modulation.

3,438 citations