1. Observational Cosmology - a laboratory for fundamental physics MPI-K, Heidelberg 24.11.2011 Marek Kowalski

2. 2Observational cosmology - Kowalski Introduction Cosmological probes Cosmological constraints Outline

3. Our Cosmological Framework derives from… Observation: The Universe is Expanding Principles: Homogeneous, isotropic Theory: General Relativity  Friedman Equation, which governs expansion

4. Our Cosmological Framework derives from… Observation: The Universe is Expanding Principles: Homogeneous, isotropic Theory: General Relativity Matter Density  Friedman Equation, which governs expansion

5. Our Cosmological Framework derives from… Observation: The Universe is expanding Principles: Homogeneous, isotropic Theory: General Relativity Matter Density Cosmological Constant/ Dark Energy  Friedman Equation, which governs expansion

6. Our Cosmological Framework derives from… Observation: The Universe is expanding Principles: Homogeneous, isotropic Theory: General Relativity Matter Density Cosmological Constant/ Dark Energy Curvature  Friedman Equation, which governs expansion

7.  MM 1998: Discovery of Dark Energy

8. 8Observational cosmology - Kowalski Nobel prize for physics 2011

9. 9Observational cosmology - Kowalski Nobel prize for physics 2011

10. 10Observational cosmology - Kowalski The standard model of cosmology: ΛCDM Ingredients of ΛCDM: Cosmological constant Cold Dark Matter Baryons 3 light neutrino flavors Ampl. of primord. fluctuations Index of power spectrum

11. 11Observational cosmology - Kowalski The standard model of cosmology: ΛCDM Beyond the standard model: Non-Λ dark energy Hot dark matter, e.g. massive neutrinos Additional relativistic species, e.g extra neutrino species Tensor perturbations & running spectral index ⇒ physics of Inflation

12. 12Observational cosmology - Kowalski Cosmological Probes: Selected new results

13. 13Observational cosmology - Kowalski WMAP New ground based data from: South Pole Telescope (SPT) & Atacama Cosmology Telescope (ACT) ACT – 6 m telescope Planck: 2009 - 2011 Cosmic Microwave Background

14. 14Observational cosmology - Kowalski WMAP: 2001 - ? w/o forground CMB fit with forground; 4σ detections of CMB weak lensing SPT SPT-after filter WMAP New ground based data from: South Pole Telescope (SPT) & Atacama Cosmology Telescope (ACT) Cosmic Microwave Background

15. 15Observational cosmology - Kowalski CMB footprint X-ray footprint Picture credit: ESA First science results of Planck (A&A, 2011) Galaxy Clusters

16. 16Observational cosmology - Kowalski SNe Ia Hubble Diagram normalization fainter then expected     M 1 0 0.72 0.28 0 1 A bit brighter   M fainter Supernova Cosmology Project (SCP) Kowalski et al. (2008)

17. 17Observational cosmology - Kowalski SNe Ia Hubble Diagram    M 1 0 0.72 0.28 0 1 fainter SNF PTF CfA PanStarrs SDSS Essence SNLS HST Supernova Cosmology Project (SCP) Kowalski et al. (2008)

18. 18Observational cosmology - Kowalski SNe at large Redshifts (z>1)

19. 19Observational cosmology - Kowalski Supernova Cosmology Project Suzuki et al., 2011 Supernova Cosmology Project Suzuki et al., 2011 Survey of z>0.9 galaxy clusters ⇒ SNe from cluster & field ⇒ about 2 x more efficient ⇒ enhencement of early hosts ⇒ 20 new HST SNe ⇒ 10 high quality z>1 SNe! Cycle 14, 219 orbits (PI S. Perlmutter) 24 clusters from RCS, RDCS,IRAC, XMM HST Survey of Clusters with z ≥ 1

20. 20Observational cosmology - Kowalski HST Survey of Clusters with z ≥ 1 Supernova Cosmology Project Suzuki et al., 2011 Supernova Cosmology Project Suzuki et al., 2011

21. 21Observational cosmology - Kowalski HST Survey of Clusters with z ≥ 1 Union 2.1 - 580 SNe

22. 22Observational cosmology - Kowalski Acoustic „oscillation“ lengh scale from CMB visible in the distribution of galaxies ⇒ Standard ruler of cosmology. Sloan Digital Sky Survey Baryon Acoustic Oscillation

23. 23Observational cosmology - Kowalski Acoustic „oscillation“ lengh scale from CMB visible in the distribution of galaxies ⇒ Standard ruler of cosmology. WiggleZ survey – Blake et al, 2011 Baryon Acoustic Oscillation

24. 24Observational cosmology - Kowalski Promising technique & much activity: BOSS, HETDEX,... Acoustic „oscillation“ lengh scale from CMB visible in the distribution of galaxies ⇒ Standard ruler of cosmology. Baryon Acoustic Oscillation

25. 25Observational cosmology - Kowalski Cosmological Constraints: Selected new results

26. 26Observational cosmology - Kowalski SNe (Union 2.1, Suzuki et. al, 2011) BAO (Percival et. al, 2010) CMB (WMAP-7 year data, 2010) and allowing for curvature: Ω k =0.002 ± 0.005 Ω Λ =0.729 ± 0.014 Supernova Cosmology Project Suzuki et al., 2011 ΛCDM

27. Fundamental Problems of Vacuum Energy/Cosmological Constant: Why so small? Expectation:    planck ) 4  120 orders of magnitudes larger then the observed value! Why now? Matter:  R -3 Vakuum Energy:  = constant Dark Energy with equation-of-state: p=w  (p = pressure;  = density)  R -3(1+w)

28. 28Observational cosmology - Kowalski cosmological constant Equation of state: p=wρ Constant w: w=-0.995±0.078 Supernova Cosmology Project Suzuki et al., 2011 Dark Energy

29. 29Observational cosmology - Kowalski cosmological constant Equation of state: p=wρ Constant w: w=-0.951±0.078 Redshift dependent w: w(a)=w 0 +(1-a) x w a W a = 0.14±0.68 No deviation from w=-1 (i.e. Λ) Λ Supernova Cosmology Project Suzuki et al., 2011 Dark Energy

30. 30Observational cosmology - Kowalski Redshift dependent EOS A floating non-SNe bin to decouple low from high-redshift constraints Assuming step-wise constant w: ~20% improved constraints

31. 31Observational cosmology - Kowalski e.g. Chaotic Inflation (Linde, 1983) Power spectrum of curvature perturbations Constraints on Inflation parameters

32. 32Observational cosmology - Kowalski e.g. Chaotic Inflation (Linde, 1983) Scalar spectral index n s =0.966±0.011 Tensor-to-scalar ratio r<0.21 Power spectrum of curvature perturbations Tensor-to-scalar ratio (r) scalar spectral index (n s ) SPT+ WMAP7 (Keisler et al. 2011) Constraints on Inflation parameters

33. 33Observational cosmology - Kowalski SPT+WMAP7: N eff = 3.85±0.62 (68% CL) CMB (& Baryon Nucleosynthesis) sensitive to number of neutrino species N eff Number of relativistic species (neutrinos!)

34. 34Observational cosmology - Kowalski Damping of correlation power due to free streaming at epoch of radiation- matter equality: Tegmark et al. 2004 Combination of CMB+BAO+H 0 : Similar mass bounds also for LSND-like sterile neutrinos e.g. Komatsu et al (2010) Hamann et al (2010) Neutrino mass from CMB & large scale structure

35. 35Observational cosmology - Kowalski Cosmology today is about precision Multiple probes for highest sensitivity ΛCDM looks strong so far – despite interpretational problems with dark energy Many new surveys committed, hence significant progress expected! Summary

36. 36Observational cosmology - Kowalski

37. 37Observational cosmology - Kowalski Counting Galaxy Clusters Vikhlini et al. ApJ, 2009 Upcoming surveys: eROSITA, DES,...

38. 38Observational cosmology - Kowalski Redshift dependent EOS A floating non-SNe bin to decouple low from high-redshift constraints Assuming step-wise constant w: