1. WEIGHING THE UNIVERSE Celebrating Tsvi Piran Neta A. Bahcall Princeton University Neta A. Bahcall Princeton University

2. MAZAL TOV, TSVI!  Happy Birthday!  PhD, HU, 1976 [ Neta: HU alum; John: HU Honorary Degree ‘03]  First papers with J. Shaham, 1975 [ my classmate, friend] 1. High Efficiency of the Penrose Mechanism for Particle Collisions 2. Can soft gamma-ray bursts be emitted by accreting black holes 4. Production of gamma-ray bursts near rapidly rotating accreting black holes 11. SS433 - A massive black hole  GRBs; GR; HEA; NS; Cosmology; Voids.. Over 200 publications  IAS Member (with John): 1979-1981; Long-Term Member ‘81-88  Happy Birthday!  PhD, HU, 1976 [ Neta: HU alum; John: HU Honorary Degree ‘03]  First papers with J. Shaham, 1975 [ my classmate, friend] 1. High Efficiency of the Penrose Mechanism for Particle Collisions 2. Can soft gamma-ray bursts be emitted by accreting black holes 4. Production of gamma-ray bursts near rapidly rotating accreting black holes 11. SS433 - A massive black hole  GRBs; GR; HEA; NS; Cosmology; Voids.. Over 200 publications  IAS Member (with John): 1979-1981; Long-Term Member ‘81-88

3. Pesach 1983, Bahcall’s home, Princeton Tsvi, Bill Press, John, Neta, Orli

4. At Safi Bahcall’s Bar-Mitzva, IAS, Princeton John, Neta, Tsvi and mother

5. Mass Density of Universe How much? How distributed?  Mass-to-Light Function  Baryon Fraction  Cluster Abundance and Evolution  Other Large-Scale Structure Obs.  All yield  m ~ 0.25  Mass ~ Light  Mass ~ Light (on large scales) How much? How distributed?  Mass-to-Light Function  Baryon Fraction  Cluster Abundance and Evolution  Other Large-Scale Structure Obs.  All yield  m ~ 0.25  Mass ~ Light  Mass ~ Light (on large scales)

6. Mass-to-Light Function M/L(R) Mass-to-Light Function M/L(R)  How does M/L depend on scale?  How and where is the mass distributed?  How use it to weigh Universe?  rep L univ (L o /Vol) =  m (M o /Vol)  Determine M, of clusters, SCs, LSS  rep [≈ 300h  rep [≈ 300h ]    m ~ 0.2 +-0.05  How does M/L depend on scale?  How and where is the mass distributed?  How use it to weigh Universe?  rep L univ (L o /Vol) =  m (M o /Vol)  Determine M, of clusters, SCs, LSS  rep [≈ 300h  rep [≈ 300h ]    m ~ 0.2 +-0.05

9. Mass-to-Light Function Mass-to-Light Function (Bahcall, Lubin & Dorman ‘95; Bahcall and Fan ‘98) 1. M/L flattens on large-scales: M ~ L. End of Dark Matter. 2. Sp + E produce M/L of groups, clusters; Clusters have no excess DM ! 3. Most of the DM is in huge halos around galaxies (few-100 Kpc) Ω m = 1.0 Ω m = 0.3 Ω m =0.25

10. Mass-to-Light Function Mass-to-Light Function (Bahcall, Lubin & Dorman ‘95; Bahcall and Fan ‘98) SDSS Ω m =0.2

11. Cluster M/L i (R) Profile (SDSS, weak lensing) 2x10 4 clusters N= 3 to 220 (Sheldon etal 2009) X=R(vir) Flat >~ 1Mpc M ~ L

12. M/L i (r=22Mpc) vs. M cl (SDSS; ‘09) Flat M/L on large scales; SAME for ALL clusters! Ω m = 0.2 +-.03

13. M/L i vs. R and M (Bahcall & Kulier ‘09)

14. M/L Function: Conclusions M/L Function Flattens on Large Scales  M/L Function Flattens on Large Scales M ~ L  M ~ L (reaching end of Dark-Matter)  Dark Matter located mostly in large galactic halos ~200s Kpc) Group/Clusters: made up of Sp+E mix (+their halos); no significant additional DM  Cluster M/L increases slightly with M (L i * ; mergers?)  Asymptotic Cluster M/L i (22Mpc) is same for ALL Groups and Clusters, 362+-54h !  Mass-Density of Univers:  m = 0.2 +- 0.03 M/L Function Flattens on Large Scales  M/L Function Flattens on Large Scales M ~ L  M ~ L (reaching end of Dark-Matter)  Dark Matter located mostly in large galactic halos ~200s Kpc) Group/Clusters: made up of Sp+E mix (+their halos); no significant additional DM  Cluster M/L increases slightly with M (L i * ; mergers?)  Asymptotic Cluster M/L i (22Mpc) is same for ALL Groups and Clusters, 362+-54h !  Mass-Density of Univers:  m = 0.2 +- 0.03

15. Cluster Abundance and Evolution Cluster Abundance and Evolution  Powerful method to determine  m and  8  8 = Amplitude of mass fluctuations  8 = Amplitude of mass fluctuations (initial ‘seeds’) (initial ‘seeds’)  n cl (z~0)   8  m 0.6 ~ 0.35  n cl (hi z)  Breaks degeneracy   m =0.2+-0.05 and  8 =0.9+-0.1   m =0.2+-0.05 and  8 =0.9+-0.1  Powerful method to determine  m and  8  8 = Amplitude of mass fluctuations  8 = Amplitude of mass fluctuations (initial ‘seeds’) (initial ‘seeds’)  n cl (z~0)   8  m 0.6 ~ 0.35  n cl (hi z)  Breaks degeneracy   m =0.2+-0.05 and  8 =0.9+-0.1   m =0.2+-0.05 and  8 =0.9+-0.1

16. Cluster Mass-Function (SDSS) (Bahcall, Dong, et al ‘03) Best-fit MF:  m =0.2 and  8 =0.9 Fit:  m =0.2  8 =0.9  8 =0.9

17.  m -  8 constraints from MF:  m = 0.2 and  8 = 0.9  m =0.2,  8 =0.9

18. m - 8 constraints from SDSS cluster MF [ Bahcall etal ‘03 Rozo etal ’09]  m =0.2,  8 =0.9

19. Cluster Abundance Evolution   8 (Bahcall & Bode ‘03) 8888

20. Cosmological Constraints (Bahcall & Bode) (from Low and Hi redshift cluster abundance) Hi z Low z

21. Weighing the Universe  M/L Function  m = 0.2 +- 0.05  Baryon Fraction 0.24 +- 0.04  Cluster Abundance 0.2 +- 0.05 and Evolution [ 8 = 0.9 +- 0.1] and Evolution [ 8 = 0.9 +- 0.1]  Supernovae Ia + Flat 0.25 +- 0.05  CMB + LSS + h + Flat 0.25 +- 0.03   m ≈ 0.23 +- 0.03  4% Baryons  Mass ~ Light (R >~ 1Mpc)  M/L Function  m = 0.2 +- 0.05  Baryon Fraction 0.24 +- 0.04  Cluster Abundance 0.2 +- 0.05 and Evolution [ 8 = 0.9 +- 0.1] and Evolution [ 8 = 0.9 +- 0.1]  Supernovae Ia + Flat 0.25 +- 0.05  CMB + LSS + h + Flat 0.25 +- 0.03   m ≈ 0.23 +- 0.03  4% Baryons  Mass ~ Light (R >~ 1Mpc)

22. Mazal Tov, Tsvi! From the Bahcall’s

23. John Bahcall: “Nova” clip 2003 (‘Dancing’)