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L. Perivolaropoulos leandros.physics.uoi.gr Department of Physics University of Ioannina

Open page. Is ΛCDM the Correct Model?. L. Perivolaropoulos http://leandros.physics.uoi.gr Department of Physics University of Ioannina. Structure of Talk. Model Classes - Key Questions. Geometric Constraints: Standard Rulers - Standard Candles.

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L. Perivolaropoulos leandros.physics.uoi.gr Department of Physics University of Ioannina

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  1. Open page Is ΛCDM the Correct Model? L. Perivolaropouloshttp://leandros.physics.uoi.gr Department of Physics University of Ioannina

  2. Structure of Talk Model Classes - Key Questions Geometric Constraints: Standard Rulers - Standard Candles Comparison of Recent Standard Candle SnIa Data: -Figure of Merit -Consistency with ΛCDM -Consistency with Standard Rulers Potential Conflicts of ΛCDM with Data: - Large Scale Velocity Flows - Cluster Halo Profiles - Emptiness of Voids - Brightness of High z SnIa Dynamical Constraints: Linear Growth of Perturbations Conclusion

  3. Candidate Model Classes Cosmological Constant Expansion History Gmn- L gmn = k Tmn Dark Energy Gmn = k (Tmmn+ T’μν) Allowed Sector Eq. of state evolution Forbidden(ghosts) Modified Gravity G’mn = k Tmmn Allowed Sector

  4. Key Questions Is General Relativity the correct theory on cosmological scales? What is the most probable form of w(z) and what forms of w(z) can be excluded? What is the consistency level of ΛCDM (GR + Λ) with cosmological observations? What is the recent progress?

  5. SnIa Obs GRB Direct Probes of the Cosmic Metric: Geometric Observational Probes Direct Probes of H(z): Luminosity Distance (standard candles: SnIa,GRB): flat Significantly less accurate probesS. Basilakos, LP, MBRAS ,391, 411, 2008arXiv:0805.0875 Angular Diameter Distance (standard rulers: CMB sound horizon, clusters):

  6. Geometric Constraints Parametrize H(z): Chevallier, Pollarski, Linder Minimize: WMAP3+SDSS(2007) data ESSENCE (+SNLS+HST) data Standard Candles (SnIa) Lazkoz, Nesseris, LPJCAP 0807:012,2008.arxiv: 0712.1232 Standard Rulers (CMB+BAO)

  7. Recent SnIa Datasets Q1: What is the Figure of Merit of each dataset? Q2: What is the consistency of each dataset with ΛCDM? Q3: What is the consistency of each dataset with Standard Rulers? J. C. Bueno Sanchez, S. Nesseris, LP, 0908.2636

  8. Figures of Merit The Figure of Merit:Inverse area of the 2σ parameter contour.A measure of the effectiveness of the dataset in constraining the given parameters.

  9. 2σ Contours of Recent Datasets GOLD06 SNLS ESSENCE UNION CONSTITUTION WMAP5+SDSS5 WMAP5+SDSS7

  10. Consistency with ΛCDM Trajectories of Best Fit Parameter Point ESSENCE+SNLS+HST data Ω0m=0.24 SNLS 1yr data The trajectories of SNLS and Constitution clearly closer to ΛCDM for most values of Ω0m Gold06 is the furthest from ΛCDM for most values of Ω0m Q: What about the σ-distance (dσ) from ΛCDM?

  11. The σ-distance to ΛCDM ESSENCE+SNLS+HST data Trajectories of Best Fit Parameter Point Consistency with ΛCDM Ranking:

  12. The σ-distance to Standard Rulers ESSENCE+SNLS+HST Trajectories of Best Fit Parameter Point Consistency with Standard Rulers Ranking:

  13. Consistency with Standard Rulers vs Consistency with ΛCDM Consistency with ΛCDM Ranking Consistency with Standard Rulers Ranking: Identical Ranking Sequence!(Independent Criteria)

  14. The σ-distance to Dynamical Dark Energy Trajectories of Best Fit Parameter Point Consistency with Dynamical Dark Energy Ranking:

  15. Comparing Ranking Sequences for ΛCDM, Standard Rulers and Dynamical Dark Energy Consistency with ΛCDM Ranking: Consistency with Standard Rulers Ranking: Identical Ranking Sequence Tests Quality of SnIa Data Reversed Ranking Sequence Consistency with Dynamical Dark Energy Ranking J. C. Bueno Sanchez, S. Nesseris, LP, 09082636

  16. Trends of Geometric Probes The 2σ parameter contour areas have improved by a factor of about 4 since 2005 while the number of filtered SnIa has increased by about the same factor. The consistency with standard rulers remains good (except for Gold06 dataset) Flat, ΛCDM remains at 1σ (or less) distance from the best fit with trend to further improve consistency with geometric probes Q: Which Dark Energy Probes have weak consistency with ΛCDM?

  17. Puzzles for ΛCDM From LP, 0811.4684 Large Scale Velocity Flows - Predicted: On scale larger than 50 h-1Mpc Dipole Flows of 110km/sec or less. - Observed: Dipole Flows of more than 400km/sec on scales 50 h-1Mpc or larger. - Probability of Consistency:1% R. Watkins et. al. , 0809.4041 Cluster and Galaxy Halo Profiles: - Predicted: Shallow, low-concentration mass profiles - Observed: Highly concentrated, dense halos - Probability of Consistency:3-5% Broadhurst et. al. ,ApJ 685, L5, 2008, 0805.2617, S. Basilakos, J.C. Bueno Sanchez, LP., 0908.1333, PRD, 80, 043530, 2009. Bright High z SnIa: - Predicted: Distance Modulus of High z SnIa close to best fit ΛCDM - Observed: Dist. Modulus of High z SnIa lower (brighter) than best fit ΛCDM - Probability of Consistency for Union and Gold06:3-6% LP and A. Shafielloo , PRD 79, 123502, 2009, 0811.2802 The Emptiness of Voids: - Predicted: Many small dark matter halos should reside in voids. - Observed: Smaller voids (10Mpc) look very empty (too few dwarf galaxies) - Probability of Consistency:3-5% P.J.E. Peebles , astro-ph/0101127, Klypin et. al. APJ, 522, 82, 1999, astro-ph/9901240

  18. Large Scale Velocity Flows From R. Watkins, H. Feldman and M. J. Hudson, 0809.4041 The dipole moment of large scale velocity flows (bulk flow) extends on scales up to 100h-1Mpc with amplitudelarger than 400km/sec. ΛCDM predicted amplitude on scale larger than 50h-1Mpc : 110km/sec

  19. Cluster Halo Profiles Navarro, Frenk, White, Ap.J., 463, 563, 1996 NFW profile: From S. Basilakos, J.C. Bueno-Sanchez and LP, PRD, 80, 043530, 2009, 0908.1333. ΛCDM prediction: The predicted concentration parameter cvir is significantly smaller than the observed. Data from:

  20. Dynamical Constraints Measure growth function of cosmological perturbations: Horizon scales Evolution of δ(sub-Hubble scales): Horizon scales James, Dutta, LP., 0903.5296 Parametrization:

  21. Dynamical Constraints Fit to LSS data: ΛCDM ΛCDM provides an excellent fit to the linear perturbations growth data best fit S. Nesseris, LP, Phys.Rev.D77:023504,2008

  22. SUMMARY The consistency of ΛCDM with geometric probes of accelerating expansion is very good and it appears to be further improving with time. There are a few puzzling potential conflicts of ΛCDM specific cosmological data mainly related with dynamical large scale structure probes. Data from dynamical probes on the linear growth of perturbations are currently not as constraining as geometric probes but they also have good consistency with ΛCDM.

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