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Understanding the Lower Redshift Universe

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Understanding the Lower Redshift Universe Understanding the Lower Redshift Universe Adi Nusser Physics Department Technion, Haifa Collaborators: ❖ Enzo Branchini ❖ Marc Davis ❖ Martin Feix (postdoc at Technion) ❖ Wojtek Hellwing (postdoc at Durham) ❖ Ziv Mikulizky (Student at Technion) ❖ Jim Peebles ❖ Steven Phelps “Happy families are all alike, every unhappy family is unhappy in its own way” –Tolstoy, Anna Karenina - J. Diamond, The Anna Karenina Principle ``Happy Community”: • All reliable large scale data tell the same story. • Very low level (but important) systematics. • LSS from Local Group to ~150Mpc - traditional and New probes The LCDM is a ``Happy model”… but a little ``moody” Therapy maybe required, perhaps by Dark sector physics no z, just fluxes Condon et al 1998 Theoretical tools Observational Support The Cosmological Principle Probing Super-Survey Scales Alternative probes of large scale motions The Cosmological Principle (Einstein 1917) . Einstein 1931 . Allen Stellen des Universums sind gleichwertig; Im speziellen solo also such die ¨ortlich gemittelte Dichte der .Sternmaterie ¨uberall gleich seine . In English . All places in the Universe are equivalent. In particular, the local, averaged density of stellar material ought to be .the same everywhere. Note . The second part of this statement is vague (not unusual for Einstein!) as the averaging process should refer to some physical scale. A more explicit Cosmological Principle is expressed by Milne (33,35). .The name (Cosmological Principle) was given by Milne. In this talk, CP implies . average ρ exists < δδ >= ξ(r) approaches zero on the “largest . scales”. Basics: cosmological principle Approaching homogeneity in LCDM 1 10 H Cosmic Variance 0 Planck cosmology 0 10 km/s/Mpc 0 H −1 σ 10 Volume for local H0 measurements <<2% accuracy in 1-2yrs −2 10 by Freedman et al 1 2 3 10 10 10 Basics: cosmological principle R [Mpc] 550 500 450 V Cosmic Variance 400 Planck cosmology 350 LSS motions Tully-Fisher 300 Dn-sigma [km/s] V 250 σ 200 150 LSS motions 100 New/old probes 50 1 2 3 10 10 10 Basis: cosmological principle R [Mpc] Approaching homogeneity in observations Dipoles in the Sky 100 NVSS data, S>10mJy && Galactic latitude |b|>10o(only 10% of the data) no redshifts, just fluxes 50 0 Dec -50 -100 -200 -150 -100 -50 0 50 100 150 200 RA Condon et al 1998 Mean number as a function of flux at 1.4GHz Angular dependence: Tiwari et al 15 The NVSS observed dipole: Solar motion in CMB frame: 369km/s, RA=168, DEC=-7 Tiwari et al 15 How to Resolve this ``Discrepancy’’? open big brackets ( (radial) peculiar velocities of galaxies SFI++, Cosmic Flows II Springob et al, Tully et al close big brackets ) B on 100Mpc/h is almost parallel to solar motion There must be a dipole component of mass fluctuations at R>100Mpc/h to account for B. This needs to considered when we compare NVSS dipole component of n(S) to theoretical predictions, e.g. LCDM ``NVSS” Dipole in 100 mocks conditioned to yield proper B Entries 100 12 Mean 0.002925 RMS 0.000935 10 8 6 4 2 0 0 0.001 0.002 0.003 0.004 0.005 0.006 0.007 0.008 0.009 0.01 Dipole This conditioning makes NVSS data consistent with LCDM at ~1sigma level Dipoles in the Sky: SDSS Alternative V Advantage of SDSS: measured redshifts! 2 Nusser 2 Nusser 2 Nusser 2 Nusser 1. BASICS 1. BASICS 1. BASICS 1. BASICS 2 2 P = w⇢vc P = w⇢2vc P = w⇢vc 2 γ =0.55 + 0.05(1 + w) γ =0P .=55w +⇢ 0v.c05(1 + w) γ =0.55 + 0.05(1 + w) 2 2 P = w⇢ c γ =0.55P += 0.05(1w⇢vc + w) 2v P = w⇢vc 2 γ =0.55 + 0.05(1 + w) γ =0P .=55w +⇢ 0v.c05(1 + w) γ =0.55 + 0.05(1 + w) ⌦γ γ =0.55 + 0.05(1⌦γ + w) β =⌦γ β = β = b ⌦γ b γb β = ⌦ /b ⌦γ /b γ b ⌦ /b γ δgalaxies bδmass δ ⌦ /b bδ ⇡ galaxies ⇡ mass δgalaxies↵ ↵bδmassβ ↵ V = H⇡¯ r + V δgalaxies↵ ¯ ↵bδmassβ ↵ gal B Vgal = H r + VB V ↵ = H¯ ↵rβ + V ↵ ⇡ gal B ↵ ¯ ↵ β ↵ γ Vgal = H r + VB f = ⌦ f = ⌦γ f = ⌦γ A reincarnation of an old idea β = f/b Tammann, Yahil & Sandage 79 and long before f β==⌦γf/b β = f/b βσgalaxies = fσmass 8 8 βσgalaxiesβ = f/b= fσmass βσgalaxies = fσmass 8 8 8 8 βσgalaxies = fσmass cz = Hr + V 8 8 cz = Hr + V cz =czHr >+ HrV cz =czHr >+ HrV czcz > <Hr Hr czcz > < Hr Hr czL <(cz Hr) >L 0 t cz < Hr L0(cz) >Lt L L(cz()cz>L) <L 0 0 t t L (cz) >L 0L0(cz) <Lt t 1. from δ(xxx) to V (xxx) - LOK0(cz) <Lt 1. from δ(xxx) to V (xxx) - LOK0(cz) <Lt 1. from δ(xxxlinear) to V theory(xxx) - OK is enough for current LSS data • 1. from δ(xxx) to V (xxx) - OK Peebles’ action method for future data and LG linear theory is enough for current LSS data linear• theory is enough for current LSS data • • linearPeebles’ theory action is enough method for for current future LSS data data and LG 2. biasing:Peebles’δgalaxies action= methodδdark but for we future know data how and to model LG that - OK • • • 6 Peebles’ action method for future data and LG 3. redshift distortions: cz = Hr + V - OK & NOK 2. biasing:• δgalaxies = δdark but we know how to model that - OK 2. biasing: δgalaxies = δdark but we know how to model that - OK 6 F.o.G: in6 general a bad e↵ect 2. biasing:3. redshiftδgalaxies distortions:= δdarkczbut= Hr we+ knowV - howOK & to NOK model that - OK 3. redshift• distortions: cz = Hr + V - OK & NOK 6 Large scale compression in the radial direction: good e↵ect 3. redshiftF.o.G: distortions:in generalcz = aHr bad+ eV↵ect- OK & NOK F.o.G:• in general a bad e↵ect • • Kaiser’s rocket e↵ect: hopless at r > 150Mpc F.o.G:Largein scale general compression a bad e↵ect in the radial direction: good e↵ect Large• scale compression in the radial⇠ direction: good e↵ect • • 1. radial• component only - not a big deal LargeKaiser’s scale rocket compression e↵ect: inhopless the radial at r > direction:150Mpc good e↵ect Kaiser’s rocket e↵ect: hopless at r > 150Mpc • 4 • > ⇠ 2. sparseness• with < 10 galaxies ⇠ 1. radialKaiser’s component rocket only e↵ect: - nothopless a big at dealr 150Mpc 1. radial component only⇠ - not a big deal • ⇠ > 1. radial component only< -4not a big deal limits us< to scales4 20 30Mpc 2. sparseness with 10 galaxies 2. sparseness• with 10 galaxies⇠ − < ⇠ 4 3. large velocity errors⇠ < 0.15H r 2. sparseness with 10 galaxies> > 0 limits us⇠ to scales 20 30Mpc limits us to scales ⇠ 20 30Mpc • > ⇠ − • spatial Malmquist⇠ bias− if galaxies are placed at r limits us to scales < 20 30Mpc < set 3. large• velocity errors ⇠0.15−H0r 3. large velocity• errors 0.15H0r < 3. large velocity errors 0⇠.15H0r ⇠ spatial Malmquist bias if galaxies are placed at rset spatial Malmquist bias if galaxies are placed at rset • ⇠ • spatial Malmquist bias if galaxies are placed at rset • Alternative V: luminosity modulation Re-visiting the basics Internal dynamics and masses of M31 and MW Luminosity variations Linear theory application to data Gaia The Cosmological Principle Alternative probes of large scale motions Galaxies as standard candles For a Schechter luminosity function (↵ = 1): − < L >L>2L =2.77L , σL>2L =0.81L ⇤ ⇤ ⇤ ⇤ < L >L>4L =4.85L , σL>4L =0.74L ⇤ ⇤ ⇤ ⇤ How do we use this? (Tamman, Yahil & Sandage 79 ) take a very large redshift survey as estimate of magnitudes, compute M = m 5log(cz)=m 5log(Hr + V ) 0 − − true magnitudes are M = m 5log(Hr) t − Simultaneously constrain a model for V and P(Mt ) by maximizing P[M = M 2.17log(1 V /cz)],assuming 0 t − − P(Mt ) does not depend on velocity. Alternative V: luminosity modulation Problems: Re-visiting the basics Internal dynamics and masses of M31 and MW Luminosity variations Linear theory application to data • coherent photometric mis-calibration: affects all Gaia The Cosmological Principle Alternative probes of large scale motions clustering studies on large scales Degree of the e↵ect • environmental dependences of the luminosity Observations give ∆M /∆δ 0.1 (this depends on the band and ⇤ ⇠ distribution: affects certainit is actuallyvelocity models zero for r-band). Re-visiting the basics 0.02 Internal dynamics and masses of M31 and MW Luminosity variations Linear theory application to data Gaia The Cosmological Principle Alternative probes of large scale motions 0.015 env: 0.1σ d Degree of the e↵ect V-signal: 2.17σ v/cz, z =0.1 Observations give ∆M /∆δ 0.1 (this* depends on the band and M 0.01 ⇤ ⇠ it is actually zero for r-band). 0.02 0.005 0.015 env: 0.1σ d 0 V-signal: 2.17100σ /cz, z =0200.1 300 400 500 600 v R [Mpc] Alternative V: luminosity* modulation: caveats M 0.01 0.005 0 100 200 300 400 500 600 R [Mpc] Theoretical tools Linear theory application to data Luminosity variations The Cosmological Principle Gaia Alternative probesTheoretical of large scale tools motions Linear theory applicationSDSS to data DR7 GalaxyLuminosity Catalog variations The Cosmological Principle real stuGaia↵ Alternative probes of large scale motions Theoretical tools Linear theory application to data Luminosity variations SDSS DR7The Cosmological GalaxyNYU Principle Value-Added CatalogGaia Catalog Alternative probes of large scale motions realSDSS stu↵ DR7 Galaxy Catalog seereal Blanton stu↵ et al.
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