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KEY EVIDENCE RELEVANT TO THE STANDARD MODEL

KEY EVIDENCE RELEVANT TO THE STANDARD MODEL. Observation Verdict Extra Yes No Assumption CMB Acoustic Peaks X Baryon Acoustic Peak X Cold Dark Matter Type 1a Supernova X +

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KEY EVIDENCE RELEVANT TO THE STANDARD MODEL

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  1. KEY EVIDENCE RELEVANT TO THE STANDARD MODEL Observation Verdict Extra Yes No Assumption CMB Acoustic Peaks X Baryon Acoustic Peak XCold Dark Matter Type 1a Supernova X + Big Bang Nucleosynthesis X Dark Energy Matter Power Spectrum X Euclidean Geometry X CMB Global Uniformity XInflation Hubble constant X Age of stars X Evolution of Clusters X Matter Budget of Groups X CMB Lensing X CMB SZ Effects (WMAP) X Other Foregrounds (HI !)X Baryons low zX Baryons in Clusters X Axis of Evil X Bullet Cluster X Quasar polarization X

  2. Hinshaw et al 2007 ratio of 2nd to 1st acoustic peaks gives baryon to dark matter fraction.

  3. Bob NicholOne parameter Standard ruler (flat,h=0.73,b=0.17) Best fit m=0.26 99.74% detection (3) Percival et al. 2006

  4. SN1a Hubble diagram (Tonry et al 2003)Reviewed in this conference by Reynald Pain

  5. Hubble constant from Sunyaev-Zeldovich Effect (Bonamente et al 2006) (Credit: Bonamente et al. 2006) SZE CEPHEIDS Cepheid-based and SZE-based agree on H0 , current uncertainty is 10-15% (Credit: Freedman et al. (2001) 2006

  6. Cosmochronometers • Detections of radioactive elements (Th & U) allow age estimates for oldest stars: putting limits on the age of the Galaxy & Universe • Using chronometer pairs Th/U, Th/Eu, etc. we find an average age of <13-14> +/- ~ 3 Gyr for the oldest stars • Technique independent of cosmological models & parameters • We are seeing dramatic improvements in abundance values due to new experimental atomic data • Experimental nuclear data along with the improved stellar data are also constraining nuclear predictions for initial radioactive abundances • These new experimental data are driving down age uncertainties • Eventually these improvements will allow for very accurate chronometric age determinations • These new more precise values could constrain cosmological parameters (Hubble constant, etc.) and cosmological models

  7. 2dF/WMAP1 matter spectrum (Cole et al 2005)

  8. Flat +ve curvature -ve curvature

  9. Basics of the Sunyaev-Zeldovich Effect CMB The electron density of the hot gas is obtained by fitting ROSAT X-ray surface brightness profiles with the 2 parameter isothermal -model ignoring the central cooling flow The decrement in TCMB is then given by with

  10. Absence of WMAP1 SZE in 31 low z clusters (Lieu, Mittaz, & Zhang ApJ 2006)

  11. Bielby & Shanks 2007 MNRAS submitted Chanda sample of 38 z=0.3 clusters ROSAT sample of 30 low z clusters

  12. Bielby & Shanks 2007 MNRAS submitted

  13. Chandra A3112 cluster central soft X-ray excessBonamente et al 2007 ApJ submitted

  14. Equal emission flux from cluster non-thermal & thermal components (Bonamente et al 2007 ApJ submitted) This can upset cluster gas mass budget: Quenby OQSCM

  15. Afshordi et al 2007 MNRAS in press WMAP3 clusters can match the SZ prediction of models on X-ray gas fraction, But even then the baryon-to-matter ratio is 30% smaller than CMB cosmic.

  16. Chandra X-ray gas fraction (Vikhlinin et al ApJ 2003)

  17. Cen & Ostriker ApJ 1999, on `Where are the baryons?’

  18. Zappacosta filament strikes back

  19. Gerrit Verschuur 2007 ApJ submitted Overlay WMAP +ve contours on HI inverted gray-scale map HI -130 to -120 km/s In general, anomalous vel. HI are in the proximity of WMAP peaks.

  20. Verschuur 2007 ApJ submitted V= - 118 km/s v= - 87 km/s

  21. WHY THE PRIMORDIAL P(k) SPECTRUM DOES NOT ACCOUNT FOR LENSING BY NON-LINEAR GROWTHS AT Z < 1 Homogeneous Universe Mass Compensation (swiss cheese) Poisson Limit

  22. Consider a tube of non-evolving randomly placed lenses Thus The magnification by the lenses and demagnification at the voids exactly compensate each other. The average beam is Euclidean if the mean density is critical. (Kibble & Lieu 2005, Lieu & Mittaz 2005)

  23. While the percentage angular magnification has an average of Its variance is given by For a large source (like CMB cold spots), this means the average angular size can fluctuate by the amount where

  24. Shanks 2007 MNRAS in press

  25. Shanks 2007 MNRAS in press

  26. MAJOR uncertainty in the matter budget of galaxy groups (like our Milky Way). Ramella et al. ESO survey of 1,168 groups at yielded , see AJ,123, 2976 This gives a mean mass density of BUT, beware of SELECTION EFFECTS due to many unobserved groups. After correcting for this, Ramella et al. (2002) estimated Thus is actually expected to be ! Similar findings also reported by Myers et al.

  27. RDCS: 50 deg², fx3. 10-14 erg/s/cm² Concordance model + Standard M-T scaling law Concordance model + Revised M-T scaling law MACS: 22 000 deg² fx  10-12erg/s/cm²

  28. XMM Lx-Tx evolution ❖ remarkable convergence Lx/Tx)z = Lx/Tx)z = 0(1+z)with = 0.65  0.28 in full agreement with Chandra (Vikhlinin et al, 2002), ASCA (Sadat et al., 1998; Novicki et al., 2003....) + local XMM Chandra D.Lumb et al., 2003

  29. Systematic on Ωm- Ω (2  c.l.) fgas method is good for Ωm, but… pay attention to systematics

  30. Top: the shear angular power spectrum computed from simulation (points) and semi-analytic calculation (curve) Bottom: fractional correction given by computing reduced shear instead of shear (curve is computed perturbatively) Dodelson, Shapiro, White. Phys Rev D 73 (2006) 023009 Are Theorists Ready for Weak Lensing Surveys?Chaz Shapiro, University of Chicago, KICP • Weak lensing tomography will probe dark energy’s effects on geometry and structure formation • Though lensing provides “clean” measurements of large scale structure (since it requires few assumptions), it is not free of theoretical uncertainties • Theory systematics include • Computational approximations • Correlated galaxy alignments • Source galaxy clustering • Non-Gaussianity • Predicting the nonlinear matter power spectrum An example of a computational systematic is the reduced shear approximation, given by g =  / (1 - ) ≈  where  is lensing shear,  is lensing convergence, and g is the reduced shear measured by observers. This 1st order approximation can significantly bias measurements from future surveys like SNAP, DES and LSST.

  31. The Axis of Evil II - Summary Correlations seen for l = 2,3,4,5 But how do we test the significance? Propose a model Frequentist Bayesian Planarity m-preference

  32. Dark Matter Exists The Bullet Cluster - an object whose visible mass and center of gravity are spatially separated. But, nature of Dark Matter is still unknown Also does not prove that gravity is Newtonian Courtesy Sean Carroll (cosmicvariance.com)

  33. Fit to the convergence map of the bullet cluster: the convergence map is compatible with MOND gravity if a component of 2eV neutrinos is present =0.16 0.23 0.3 0.37

  34. AstroTheo Meeting Liege Large-scale alignments of quasar polarization vectors • Evidence for large-scale angular correlations of quasar polarization vectors (in regions of ~ 1 Gpc size at z ~ 1) • The mean polarization angle changes with redshift • The effect is statistically significant (> 99.9%) in a sample of 355 quasars • Instrumental and interstellar polarization cannot produce a redshift dependent effect • The effect seems stronger along an axis close to the CMB dipole and the “axis of evil” • A large-scale origin might be due to a modification of the quasar polarization along the line of sight (photon-pseudoscalar conversion? large-scale rotation?) and/or assuming intrinsic remnant alignments of quasar axes • The regions of alignments might be among the largest structures in the Universe and indicate departures to the fundamental cosmological assumption of large-scale isotropy (Reference : Hutsemékers et al. A&A 2005, 441, 915) z > 1

  35. If the fluctuations from inflation have a small ‘bump’ in their spectrum … caused perhaps by SUSY phase transitions in the cooling universe Do CMB & LSS data require dark energy? - Subir Sarkar (Oxford) To explain large-scale structure requires 15% hot dark matter (3x 0.8 eV mass ’s) The WMAP data can be fitted with Ωmrequires only that h ~ 0.46

  36. Rasanen 2007 • The FRW equations do not describe the average expansion of inhomogeneous spaces. • The equations for inhomogeneous space show that even when the local expansion decelerates everywhere, the average expansion can accelerate. • Acceleration can be due to collapsing regions. • Structure formation involve collapsing regions and has a preferred time around the observed acceleration era.

  37. GRAND SUMMARY • Over several precision cosmology datasets the standard cosmological model has staggering success. • Yet there are definitely major problems concerning many other observations the model cannot explain. It would be a mistake to undermine this. • Perhaps the standard model as it stands is like Bohr’s model of the H-atom. The Cophenhagen interpretation is yet to come.

  38. Future Priorities Dark Matter • PLANCK: CMB polarization peaks  • Acoustic nature of CMB peaks & DM potential • PLANCK: is the 3rd TT peak lensed? • Weak lensing shear maps • Strong lensing time delay • More bullet clusters • Mass and no. density of galaxy GROUPS Dark Energy • Integrated Sachs-Wolfe Effect – direct probe of dark energy and constraint on w.

  39. Missing Baryons • Are they in a warm (10^6 K) gas? • Non-thermal activity in clusters? Implications on SZ effect, scaling laws and cluster evolution.

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