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Observations are converging

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Observations are converging…. …to an unexpected universe. Classifying the unknown, 1. Cosmological constant Dark energy w=const Dark energy w=w(z) quintessence scalar-tensor models coupled quintessence mass varying neutrinos k-essence Chaplygin gas Cardassian quartessence - PowerPoint PPT Presentation
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  • ISAPP 2011Observations are convergingto an unexpected universe

    ISAPP 2011

  • ISAPP 2011Classifying the unknown, 1 Cosmological constant Dark energy w=const Dark energy w=w(z) quintessence scalar-tensor models coupled quintessence mass varying neutrinos k-essence Chaplygin gas Cardassian quartessence quiessence phantoms f(R) Gauss-Bonnet anisotropic dark energy brane dark energy backreaction void models degravitation TeVeS oops....did I forget your model?

    ISAPP 2011

  • ISAPP 2011Classifying the unknown, 3

    a) change the equations i.e. add new matter field (DE) or modify gravity (MG)b) change the symmetriesi.e. inhomogeneous non-linear effects, void models, etcStandard cosmology:GR gravitational equations + symmetries

    ISAPP 2011

  • ISAPP 2011

    L = crossover scale:

    5D gravity dominates at low energy/late times/large scales4D gravity recovered at high energy/early times/small scales 5D Minkowski bulk:infinite volume extra dimensiongravity leakagebraneSimplest MG (I): DGP(Dvali, Gabadadze, Porrati 2000)

    ISAPP 2011

  • ISAPP 2011 f(R) models are simple and self-contained (no need of potentials) easy to produce acceleration (first inflationary model) high-energy corrections to gravity likely to introduce higher-order terms particular case of scalar-tensor and extra-dimensional theoryeg higher order corrections The simplest MG in 4D: f(R)Simplest MG (II): f(R)

    ISAPP 2011

  • ISAPP 2011 Faces of the same physics Extra-dim. degrees of freedomHigher order gravity

    Coupled scalar fieldScalar-tensor gravityFaces of the same physics

    ISAPP 2011

  • ISAPP 2011 Is this already ruled out by local gravity? is a scalar-tensor theory with Brans-Dickeparameter =0 or a coupled dark energy model with coupling =1/2Adelberger et al. 2005

    ISAPP 2011

  • ISAPP 2011 The fourfold way out of local constraints {depend on timedepend on spacedepend on local densitydepend on species

    ISAPP 2011

  • ISAPP 2011 The simplest case In Einstein FrameTurner, Carroll, Capozzielloetc. 2003 a particular case ofcoupled dark energy

    ISAPP 2011

  • ISAPP 2011 R-1/R model : the MDE radmatfieldradmatfieldMDEtodayCaution:Plots in theEinstein frame!instead of !!In Jordan frame:

    ISAPP 2011

  • ISAPP 2011Sound horizon in R+R - n model L.A., D. Polarski, S. Tsujikawa, PRL 98, 131302, astro-ph/0603173in the Matter Era !

    ISAPP 2011

  • ISAPP 2011 A recipe to modify gravityCan we find f(R) models that work?

    ISAPP 2011

  • ISAPP 2011cLGC+CosmologyTake for instance the CDM cloneApplying the criteria of LGC and background cosmology i.e. CDM to an incredible precision

    ISAPP 2011

  • ISAPP 2011Space-time geometry

    The most general (linear, scalar) metric at first-order

    Full metric reconstruction at first order requires 3 functions backgroundperturbations

    ISAPP 2011

  • ISAPP 2011Two free functions

    At linear order we can write:

    Poisson equation

    zero anisotropic stress

    ISAPP 2011

  • ISAPP 2011Two free functions modified Poisson equation

    non-zero anisotropic stress

    At linear order we can write:

    ISAPP 2011

  • ISAPP 2011Modified Gravity at the linear level scalar-tensor models

    standard gravity DGP

    f(R)

    Lue et al. 2004; Koyama et al. 2006Bean et al. 2006Hu et al. 2006Tsujikawa 2007 coupled Gauss-Bonnet

    see L. A., C. Charmousis, S. Davis 2006Boisseau et al. 2000Acquaviva et al. 2004Schimd et al. 2004L.A., Kunz &Sapone 2007

    ISAPP 2011

  • ISAPP 2011 Reconstruction of the metricmassive particles respond to massless particles respond to -

    ISAPP 2011

  • ISAPP 2011 Reality checkMatter power spectrumGalaxy power spectrumGalaxy power spectrumin redshift spaceDensity fluctuation in space

    ISAPP 2011

  • ISAPP 2011 Peculiar velocities.r = v/H0

    ISAPP 2011

  • ISAPP 2011 Peculiar velocitiesredshift distortion parameterKaiser 1987

    ISAPP 2011

  • ISAPP 2011ObserverDark matter halosBackground sourcesWeak lensing

    ISAPP 2011

  • ISAPP 2011 The Euclid theoremWe can measure 3 combinations and we have 1 theoretical relation Observables: Conservation equations: Theorem: lensing+galaxy clustering allows to measure all (total matter) perturbation variables at first order without assuming any specific gravity theory 4 unknown functions:

    ISAPP 2011

  • ISAPP 2011 The Euclid theoremFrom these we can derive the deviations from Einsteins gravity:

    ISAPP 2011

  • Euclid SurveysSimultaneous (i) visible imaging (ii) NIR photometry (iii) NIR spectroscopy20,000 square degrees100 million redshifts, 2 billion imagesMedian redshift z = 1PSF FWHM ~0.18Final ESA selection (launch 2017)500 peoples, 10 countries Euclid in a nutshellEuclid satellite

    ISAPP 2011

  • Bertinoro 2011Real-time cosmology

    Bertinoro 2011

  • ISAPP 2011One null cone timecomoving dist.

    ISAPP 2011

  • ISAPP 2011One null cone VOID timecom. dist.One null cone

    ISAPP 2011

  • ISAPP 2011Cosmic Degeneracy 3void modelGarcia-Bellido & Haugbolle 2008Tomita 2001Celerier 2001Alnes & Amarzguioi 2006,07Bassett et al. 07 Clifton et al. 08Notari et al. 2005-08Marra et al. 08Garcia-Bellido & Haugbolle 2008

    ISAPP 2011

  • ISAPP 2011Two null cones are better than one!VOID timecom. dist.Mashhoon & Partovi 1985Uzan, Clarkson & Ellis 2007Quartin, Quercellini, L.A. 2009

    ISAPP 2011

  • ISAPP 2011Sandage 1962

    ISAPP 2011

  • ISAPP 2011Loeb 1998

    ISAPP 2011

  • ISAPP 2011The Sandage effectCorasaniti, Huterer, Melchiorri 2007Balbi & Quercellini 2007

    ISAPP 2011

  • ISAPP 2011EELT

    ISAPP 2011

  • ISAPP 20112010CODEX at EELTtoday......ten years later

    ISAPP 2011

  • ISAPP 2011CODEX at EELTLiske et al. 2008 large colleting area high resolution spetrographs stable, low-peculiar motion targets: Lyman-alpha lines

    ISAPP 2011

  • ISAPP 2011Two null cones are better than one!VOID timecom. dist.Two null cones are better than one!M. Quartin & L. A. 20095yrs10yrs15yrs

    ISAPP 2011

  • ISAPP 2011LTB void model, XXI centuryEvolutionUsRest of the UniversePtolemaic system, I century UsRest of the Universe

    ISAPP 2011

  • ISAPP 2011

    Quercellini, Quartin & LA, Phys. Rev. Lett. 2009arXiv 0809.3675LTB void modelCosmic Parallaxastrometric satellitesGAIA, SIM, Jasmine etc: 1-100 as

    ISAPP 2011

  • ISAPP 2011Lemaitre-Tolman-Bondi modelsExact solution in matter-dominated universe:Garcia-Bellido & Haugbolle 2008

    ISAPP 2011

  • ISAPP 2011

    Quercellini, Quartin & LA, arXiv 0809.3675Garcia-Bellido & Haugbolle 2008

    ISAPP 2011

  • ISAPP 2011Gaia: Complete, Faint, Accurate

    ISAPP 2011

    Hipparcos

    Gaia

    Magnitude limit

    12

    20 mag

    Completeness

    7.3 9.0

    20 mag

    Bright limit

    0

    6 mag

    Number of objects

    120 000

    26 million to V = 15

    250 million to V = 18

    1000 million to V = 20

    Effective distance limit

    1 kpc

    50 kpc

    Quasars

    None

    5 x 105

    Galaxies

    None

    106 107

    Accuracy

    1 milliarcsec

    7 arcsec at V = 10

    10-25 arcsec at V = 15

    300 arcsec at V = 20

    Photometry photometry

    2-colour (B and V)

    Low-res. spectra to V = 20

    Radial velocity

    None

    15 km/s to V = 16-17

    Observing programme

    Pre-selected

    Complete and unbiased

  • ISAPP 2011

    Quercellini, Quartin & LA, arXiv 0809.3675Cosmic Parallax

    ISAPP 2011

  • ISAPP 2011

    Quercellini, Quartin & LA, arXiv 0809.3675Garcia-Bellido & Haugbolle 2008

    ISAPP 2011

  • ISAPP 2011

    Quercellini, Quartin & LA, arXiv 0809.3675Garcia-Bellido & Haugbolle 2008

    ISAPP 2011

  • ISAPP 2011Bianchi INot only LTBa(t)b(t)c(t)

    ISAPP 2011

  • ISAPP 2011Current limits on anisotropyat z = 1000at z = 0 in a CDM universeat z = 0 in anisotropic dark energy

    ISAPP 2011

  • ISAPP 2011Anisotropic dark energyMota & Koivisto 2008, Barrow, Saha, Bruni, Rodrigues and many others..C. Quercellini, P. Cabella, L.A., M. Quartin, A. Balbi 2009

    ISAPP 2011

  • ISAPP 2011Future of Dark Energy research

    Move from background to perturbationsTest for gravity/new physics at large scalesNew full sky surveys at redshift beyond unityFind new observables: eg real-time cosmology

    ISAPP 2011

  • ISAPP 2011Peculiar AccelerationThe PA is a direct probe of thegravitational potential: itdoes not assume virialization orhydrostatic equilibrium.

    ISAPP 2011

  • ISAPP 2011Peculiar Acceleration

    MassAndromeda 20 kpcVirgo 0.55 MpcComa 0.29 Mpc

    ISAPP 2011

  • ISAPP 2011Peculiar AccelerationL.A., A. Balbi, C. Quercellini, astro-ph arXiv/0708.1132Phys.Lett.B660:81,2008 differentlines of sight

    ISAPP 2011

  • ISAPP 2011local versus globalClusterMassLCDMredshift driftpec. acc.

    ISAPP 2011

  • ISAPP 2011Peculiar acceleration in the Galaxy

    Can we use the peculiar acceleration to discriminate among competing gravity theories ?Steps:We model the galaxy as a disc+CDM halo and derive the peculiar acceleration signalWe model the galaxy as a disc in modified gravity (MOND)We analyse the different morphology of the signal in the Milky way

    ISAPP 2011

  • ISAPP 2011

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