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The Dark Matter Crisis: Problems with the Current Standard Model of Cosmology and Steps Towards an Improved Model

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The Dark Matter Crisis: Problems with the Current Standard Model of Cosmology and Steps Towards an Improved Model The dark matter crisis: problems with the current standard model of cosmology and steps towards an improved model Pavel Kroupa Helmholtz-Institut fuer Strahlen und Kernphysik (HISKP) University of Bonn AAS Topical Meeting "Probes of Dark Matter on Galaxy Scales" Monterey, CA, 14-19 July 2013 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 1 Standard model of physics : Computation and prediction of dynamical structures (particles and their excited states). Until now excellent agreement with experiments (e.g. LHC). Standard model of cosmology : Computations and predictions of dynamical structures (galaxies and their satellite galaxies). This talk. Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 2 Standard model of cosmology : Postulate I : Einstein's field equation is valid everywhere Postulate II : Matter is conserved Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 3 Standard model of cosmology : Assumptions are immediately falsified : - Prediction of a highly curved highly inhomogeneous universe - Prediction of falling rotation curves of galaxies and structure formation too slow Solution: not understood - Postulate a mathematical trick (inflation) - Postulate existence of unknown exotic matter (dark matter) not found But this also does not work: - Universe expands today faster, than it should Solution: not understood - Postulate a mathematical trick (dark energy) Problem : - Model (=Standard Model of Cosmology = LCDM) does not conserve energy Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 4 The standard model of cosmology (SMoC) : fix its parameters such that it accounts for the observed large-scale structure. Assume it is a valid description of the universe, then test on intermediate and galactic scales where data are excellent . Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 5 Consequence I Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 6 Structures form according to the cosmological merger tree the beginning Big Bang Lacey & Cole (1993) DM sub- structures form first and coalesce to larger structures today Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 7 250 kpc ≈ Astrophysics of Galaxies VIII: LG Donnerstag, 18. Juli 13 8 Consequence II Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 9 Structures form according to the cosmological merger tree the beginning Lacey & Cole (1993) galaxies interact and merge TDGs = tidal dwarf galaxies form today Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 10 Tidal tails Miho & Maxwell, web Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 11 (Weilbacher et al. 2000) NTDG ≈ 14 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 12 (Weilbacher et al. 2000) bulge Phase-space correlated formation satellites form naturally in the same event as a bulge does. TDG formation Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 13 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 14 Relevance : The collision of two disks at high redshift Wetzstein, Naab & Burkert 2007 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 15 Wetzstein, Naab & Burkert 2007 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 16 (Weilbacher et al. 2000) NTDG ≈ 14 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 17 Thus in the Standard Model of Cosmology (SMoC) a galaxy must look as follows: phase-space spheroidal correlated distribution distribution + DM satellites + TDG satellites have different properties Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 18 The Dual Dwarf Galaxy Theorem must be true if the SMoC is true : The Dual Dwarf Galaxy Theorem : E V Kroupa 2012 SMoC ⇒ Type A dwarfs Type B dwarfs with Dark Matter (DM) TDGs w/o DM spheroidal phase-space distribution correlation If only one type exists then the Dual Dwarf Galaxy Theorem is falsified. Is there any evidence for the co-existence of two types of dwarf galaxy ? Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 19 The Gentile et al., 2007 Baryonic Tully -Fisher Relation : If the SMoC is true the BTFR then the BTFR must be given by the dark matter halo and tidal dwarf galaxies } dark matter cannot objects lie on the same BTFR ! Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 20 The Gentile et al., 2007 Baryonic Tully -Fisher Relation : the BTFR But TDGs do lie on the same BTFR !? TDGs TDGs Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 21 Types of stellar systems Dabringhausen et al. 2012 only one 4 10 type of dwarf galaxy exists ! 103 102 101 projected half-light radius [ pc ] GCs / UCDs elliptical galaxies 100 fit to giant ellipticals fit to dwarf ellipticals 102 104 106 108 1010 1012 stellar mass [ M ] ! Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 22 Types of stellar systems Dabringhausen et al. 2012 104 TDGs coincide with 3 10 dE / dSph satellites 102 101 projected half-light radius [ pc ] GCs / UCDs elliptical galaxies 100 observed TDGs numerical calculations 102 104 106 108 1010 1012 stellar mass [ M ] ! Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 23 Thus: Kroupa 2012; Dabringhausen & Kroupa 2013 The Dual Dwarf Galaxy Theorem : V SMoC ⇒ E Type A dwarfs Type B dwarfs only one type of dwarf galaxy is observed. Dual Dwarf Galaxy Theorem is falsified. ⇔ Type A dwarf = Type B dwarf ⇒ SMoC has been shown Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 24 Remember : The Dual Dwarf Galaxy Theorem must be true if the Kroupa 2012; SMoC is true : Dabringhausen & Kroupa 2013 The Dual Dwarf Galaxy Theorem : V SMoC ⇒ E Type A dwarfs Type B dwarfs with DM TDGs w/o DM spheroidal phase-space distribution correlation consistency check next . Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 25 Consistency Check I If the Milky Way satellites are TDGs without dark matter then they ought to be in a phase-space correlated distribution. Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 26 Vast Polar Structure around the Milky Way Pawlowski et al. 2012 YH globular clusters dSph satellites UFD satellites See also YouTube video "The Vast Polar Structure" streams Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 27 Vast Polar Structure around the Milky Way Pawlowski et al. 2012 YH globular clusters dSph satellites UFD satellites See also YouTube video "The Vast Polar Structure" streams Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 28 Vast Polar Structure around the MW Pawlowski et al. 2012 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 29 If the MW satelites are DM dominated sub-halos, then A) they have to have fallen-in recently (z<1) in order to be arranged in the DoS/VPOS Deason et al. (2011) AND B) they have to have fallen in a long time ago (z=3-10) in order for them to have lost their gas Nichols & Bland-Hawthorn (2011) A and B are mutually exclusive. ==> logical inconsistency of the model Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 30 Phase-space-correlated tidal debris Pawlowski et al. 2012 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 31 Fly-by encounter: e.g. Milky Way and Andromeda ? about 10-11 Gyr ago Pawlowski et al. 2011 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 32 Consistency Check II Other, extra-galactic, phase-space correlated distributions of satellite systems. Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 33 Bournaud et al. (2007, Science) observed model Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 34 Bournaud et al. (2007, Science) observed model Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 35 Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 36 Duc et al. (2011 (post-merger 2-3 Gyr) NGC 5557 MNRAS) 200 kpc ≈ dSph dSph Text dSph (Kroupa et al. 2010) Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 37 Tollerud et al. (2011, Andromeda MNRAS) Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 38 Tollerud et al. 2011, Andromeda Ibata et al. 2013, Nature; Conn et al. 2013) 50 % of all satellites are in thin disk (14 : 400kpc). Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 39 The formation of faint dwarf galaxies in the interaction between two spirals (NGC 3169) Credit: Martinez-Delgado (ZAH) and Adam Block (MtLemmon Obs) Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 40 GALEX image (NGC 3169) From: Martinez-Delgado (ZAH) Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 41 Remember : Kroupa 2012 The Dual Dwarf Galaxy Theorem must be true if the SMoC is true : The Dual Dwarf Galaxy Theorem : V SMoC ⇒ E Type A dwarfs Type B dwarfs with DM TDGs w/o DM spheroidal phase-space distribution correlation consistency check next . Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 42 Thus: Kroupa 2012 The Dual Dwarf Galaxy Theorem : V SMoC ⇒ E Type A dwarfs Type B dwarfs only one type of dwarf galaxy is observed. Dual Dwarf Galaxy Theorem is falsified. ⇔ Type A dwarf = Type B dwarf ⇒ SMoC has been shown Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 43 If this falsification is true, then the standard model of cosmology must show other and general discrepancies with data . Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 44 The Theory Confidence Graph Kroupa 2012 angular momentum cusp/core missing satellites down sizing DoS (later VPOS) TDG mass deficit invariant disk galaxies common DM mass scale of satellite galaxies constant surface density MFn of luminous sub-halos bulgeless disk galaxies isolated massive galaxies Local Void too empty Bullet cluster missing massive satellites thin old disk Train-Wreck cluster missing dark matter massive galaxy clusters Pavel Kroupa: University of Bonn Donnerstag, 18. Juli 13 45 Kroupa 2012 Failure 14 : 58–74 per cent of all observed disk galaxies are claimed to not have a classical bulge (Kormendy et al.
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