Modern advances in galactic astrophysics : from scale-invariant dynamics to a successful theory of galaxy formation and evolution.

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1 Modern advances in galactic astrophysics : from scale-invariant dynamics to a successful theory of galaxy formation and evolution Lecture 3 Structures on large scales and performance of the SMoC; Correlations in the properties of galaxies: Galaxies are simple systems Selected Chapters on Astrophysics Charles University, Praha, December & January 2016/17 Pavel Kroupa Helmholtz-Institute for Radiation und Nuclear Physics (HISKP) University of Bonn Astronomical Institute, Charles University in Prague c/o Argelander-Institut für Astronomie University of Bonn Lecture 1 ( ) : The standard model of cosmology (SMoC) and the arguably greatest question of 20th/21st century physics : Do the postulated dark matter particles exist? Lecture 2 ( ) : Further on dynamical friction : evidence for merging galaxies. Galaxy populations. Lecture 3 ( ) : Structures on large scales and performance of the SMoC; Correlations in the properties of galaxies I : Galaxies are simple systems. Lecture 4 ( ) : Correlations in the properties of galaxies II. Evidence for a new law of nature : space-time scale-invariant dynamics. Some steps towards a deeper theoretical understanding.

2 Remember: Observed DoSs readily understandable as tidal-dwarf galaxy populations. "Missing satellite problem" becomes disastrous => incompatibility with SMoC. TDGs cannot be dominated by dark matter. Their observed very high dynamical M/L ratios could be an apparent effect due to repeated tidal shaping. Vast majority of galaxies with Mbaryon > Msun are disk galaxies. => galaxies do not form from many mergers => incompatibility with SMoC. Renzo's rule contradicts dark matter halos => incompatibility with SMoC. Buildup with time of massive galaxies not observed => incompatibility with SMoC. Too many compact groups of galaxies => incompatibility with SMoC. 3 How to proceed? But supposedly, SMoC is fine on scales larger than those of galaxies, on which it is generally thought that baryonic physics is not understood such that the calculations do not yet agree with the observations. But in Lecture 1 we already saw that the Local Group (scale of 100kpc - 3Mpc) has a spatial distribution of matter which is incompatible with the SMoC. Here baryonic processes cannot play a role. Lets study even larger scales, larger than 3Mpc. 1: The distribution of galaxies within 8 Mpc. 2: The distribution of galaxies within 800 Mpc. 4

Structures form according to the cosmological merger tree the beginning Big Bang Lacey & Cole (1993) DM substructures form first and coalesce to larger structures today 5 Peebles & Nusser 2010,

The ten most luminous galaxies (including M31 and the Milky Way at D < 1 Mpc) are indicated by the open circles. The orthogonal projections are plotted in supergalactic coordinates.

3 Structures form according to the cosmological merger tree the beginning Big Bang Lacey & Cole (1993) DM substructures form first and coalesce to larger structures today 5 Peebles & Nusser 2010, Nature The Local Sheet is the concentration along the centre plane, and the Local Void is the region on the upper left in the left-hand projection. The ten most luminous galaxies (including M31 and the Milky Way at D < 1 Mpc) are indicated by the open circles. The orthogonal projections are plotted in supergalactic coordinates. Black filled circles: 337 galaxies largely discovered on photographic plates and with wellmeasured distances. Red triangles: 172 galaxies added by the Sloan Digital Sky Survey (SDSS), with redshift errors of less than 50 km s 1. Blue squares: 53 galaxies discovered by the H i Parkes All Sky Survey (HIPASS) from 21-cm emission by atomic hydrogen. SDSS and HIPASS have less secure redshift distances and cover only the parts of the sky roughly indicated by the red and blue curves, respectively. There are many more dwarf galaxies to be discovered at this distance. 6

4 Peebles & Nusser 2010, Nature : Local void is too empty => "We conclude that there is a good case for inconsistency between the theory and our observations of galaxies in the Local Void." Large / massive galaxies too far from sheet : "Among the ten most luminous galaxies in Fig. 1, the spirals M51, M101 and NGC 6946 are respectively 2.4, 2.8 and 4.0 Mpc above the centre plane of the Local Sheet. They are in an uncrowded region: of the 562 known galaxies with 1 < D < 8 Mpc, only 5.0% are more than 2 Mpc above the Local Sheet (whereas 73% of the known galaxies are within 2 Mpc of the plane and the rest are below the plane). However, 30% of the largest galaxies are more than 2 Mpc above the Local Sheet. If galaxy luminosities were randomly assigned, this situation would have a 1% probability, but the probability is less than this in the standard picture of the cosmic web, in which more-luminous galaxies avoid less dense regions. These three could not be dwarfs masquerading as large galaxies; their circular velocities indicate the central masses of large galaxies. That is, the presence of these three large galaxies in the uncrowded region above the Local Sheet is real, and at well below 1% probability it is an unlikely consequence of standard ideas." 7 Measured matter density as a function of distance Kroupa

... wherever we look with the best data we have, the distribution of matter turns out to be inconsistent with the SMoC, on scales 100kpc - 300 Mpc... there is more structure with more regularities.

5 ... wherever we look with the best data we have, the distribution of matter turns out to be inconsistent with the SMoC, on scales 100kpc Mpc... there is more structure with more regularities... 9 As an aside: evidence for anisotropic cosmic expansion (a possible violation of the cosmological principle?) Subdivide SN1a sky into equally-sized regions and fit LCDM models to each individually Alignment with CMB anomalies!! Javanmardi et al. (2015, ApJ) 10

Markus Chown, 22.10.2005, New Scientist "But if Vale s idea is correct [the anomaly being caused by a supercluster], it raises a new question.

So the true quadrupole must be even smaller, and no one knows how that could have happened. I might have solved one problem but created another, admits Vale.

6 Markus Chown, , New Scientist "But if Vale s idea is correct [the anomaly being caused by a supercluster], it raises a new question. The measured quadrupole signal is already much smaller than expected by theory, and Vale s mechanism would mean that some of that signal is actually spillover from the dipole. So the true quadrupole must be even smaller, and no one knows how that could have happened. I might have solved one problem but created another, admits Vale. It is possible that some feature of the big bang may have suppressed the quadrupole signal. One such scenario is that the universe is a peculiar shape like a flat slab or a doughnut. That way some of the sloshing motions of matter that caused the temperature variations in the cosmic background would not have been able to occur, says Vale." 11 As another aside: evidence for cosmic inhomogeneity (a possible violation of the cosmological principle) Meszaros, Balasz et al. (2009): "the short GRBs suggest the presence of structures of the Gpc scales. This is a great challenge to cosmology" See also Meszaros et al. (2000); Vavrek, Balasz, Meszaros et al. (2008). Confirmed by Tarnopolski, 2015, arxiv "the significance of the detected anisotropy is 99.99%" An interesting finding : very highly significant anisotropy of galaxy morphological types, but not in numbers of galaxies. Javanmardi & Kroupa (2016) 12

7 Galaxy morphological classification An anisotropic distribution of galaxy types? From Wikipedia: 13 Galaxy morphological classification An anisotropic distribution of galaxy types? (2017) 14

8 Galaxy morphological classification An anisotropic distribution of galaxy types? Javanmardi & Kroupa Galaxy morphological classification An anisotropic distribution of galaxy types? Javanmardi & Kroupa

9 Galaxy morphological classification An anisotropic distribution of galaxy types? Javanmardi & Kroupa Galaxy morphological classification An anisotropic distribution of galaxy types? Javanmardi & Kroupa

10 Galaxy morphological classification An anisotropic distribution of galaxy types? Javanmardi & Kroupa Galaxy morphological classification An anisotropic distribution of galaxy types? Javanmardi & Kroupa 2017 Note: the number of galaxies is isotropic! 20

11 The Southern Celestial Hemisphere appears to contain relatively more S0 and Sc galaxies. The Northern Celestial Hemisphere appears to contain relatively more ce and Sb galaxies. Noteworthy is that the CMB WMAP and PLANCK data show a significant Ecliptic North-South asymmetry : the North having a significantly smaller variance and stronger power spectrum. (Planck Collaboration, Ade, Aghanim et al. 2014, A&A 571, A23 Hansen et al. 2009, ApJ 704, 1448 Javanmardi & Kroupa 2017) The dichotomy line is about the Celestial equator or the Ecliptic. It appears unnatural that the orientation of the Solar System should bear on the cosmic distribution of galaxy morphological types. The asymmetry may be due to an issue with the catalogue? 21 The evidence obtained until now appears to show that the standard model of cosmology (the SMoC) may need to be ruled out : The model is in conflict with data on all scales. Even the cosmological parameters as derived from local data are in tension with those obtained from PLANCK-CMB data (Riess, Macri et al. 2016, ApJ 826, 56; Beaton, Freedman et al. 2016, ApJ 832, 210). 22

Beaton, Freedman et al. 2016, Even the cosmological parameters as derived from local data are in tension with those obtained from PLANCK-CMB data (Riess, Macri et al.

12 Beaton, Freedman et al. 2016, Even the cosmological parameters as derived from local data are in tension with those obtained from PLANCK-CMB data (Riess, Macri et al. 2016, ApJ 826, 56; Beaton, Freedman et al. 2016, ApJ 832, 210). 23 The evidence obtained until now appears to show that the standard model of cosmology (the SMoC) may need to be ruled out : The model is in conflict with data on all scales. Even the cosmological parameters as derived from local data are in tension with those obtained from PLANCK-CMB data (Riess, Macri et al. 2016, ApJ 826, 56; Beaton, Freedman et al. 2016, ApJ 832, 210). Further ideas, also e.g. on the nature of the CMB : e.g. Fahr & Heyl, 2016arXiv F Moffat, 2005, JCAP If this is true, then the standard model of cosmology must show other and general discrepancies with data... 24

13 How can one test if a given theory is to be retained or discarded? 25 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 Further: 23-27: additional failures (Kroupa, in preparation) 28) z>2.5 Gyr massive galaxies too old and massive (Castro-Rodrigues & Lopez-Corredoira 2012) 29) massive galaxies at high redshift far too compact (Lopez-Corredoira 2010) 30) Discrepancy of H0 from CMB and SN1a (arxiv: , arxiv: ) 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 26

14 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 Further: 23-27: additional failures (Kroupa, in preparation) 28) z>2.5 Gyr massive galaxies too old and massive (Castro-Rodrigues & Lopez-Corredoira 2012) 29) massive galaxies at high redshift far too compact (Lopez-Corredoira 2010) 30) Discrepancy of H0 from CMB and SN1a (arxiv: , arxiv: ) 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 27 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 Further: 23-27: additional failures (Kroupa, in preparation) 28) z>2.5 Gyr massive galaxies too old and massive (Castro-Rodrigues & Lopez-Corredoira 2012) 29) massive galaxies at high redshift far too compact (Lopez-Corredoira 2010) 30) Discrepancy of H0 from CMB and SN1a (arxiv: , arxiv: ) 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 28

15 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 Further: 23-27: additional failures (Kroupa, in preparation) 28) z>2.5 Gyr massive galaxies too old and massive (Castro-Rodrigues & Lopez-Corredoira 2012) 29) massive galaxies at high redshift far too compact (Lopez-Corredoira 2010) 30) Discrepancy of H0 from CMB and SN1a (arxiv: , arxiv: ) 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 29 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 Further: 23-27: additional failures (Kroupa, in preparation) 28) z>2.5 Gyr massive galaxies too old and massive (Castro-Rodrigues & Lopez-Corredoira 2012) 29) massive galaxies at high redshift far too compact (Lopez-Corredoira 2010) 30) Discrepancy of H0 from CMB and SN1a (arxiv: , arxiv: ) 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 30

16 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 Further: 23-26) see Kroupa (2014, Seychelles meeting) 27) z>2.5 Gyr massive galaxies too old and massive (Castro-Rodrigues & Lopez-Corredoira 2012; Steinhardt, Capak et al. 2016) 28) massive galaxies at high redshift far too compact (Lopez-Corredoira 2010) 29) Discrepancy of H0 from CMB and SN1a (arxiv: , arxiv: ) 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 failures : If each causes a loss of confidence in the theory of (only) 30%, then the confidence in the SMoC remains at or %. 32

17 Which argument remains according to which we should retain the SMoC?... so lets from now on consider the SMoC as being invalid. How do we proceed from here? Panik? thus, the observational data disfavour the existence of dark matter (SMoC leads to wrong structures and lack of dynamical friction disfavors dark matter particles) How do we proceed from here? Clue : galaxies are cosmological objects / tracers. So let us study their properties to perhaps obtain indications / evidence for an improved theoretical framework on gravitation and cosmology. 34

18 Lets return to galaxies -- these are cosmological objects with good observational constraints, so we may obtain clues. This is similar to Newton, who used Terrestrial and Solar System data to formulate an empirical classical law of gravitation. Remember this slide : Disk galaxies are thus by far the dominant population. Ellipticals are the small exception -- cosmic accidents as it were. What are the properties of disk galaxies? 35 Galaxies : are they complex or simple systems? Consider some correlations between their parameters 36

19 "New Lessons from the HI Size-Mass Relation of Galaxies" Wang, Koribalski et al., 2016 "The relation between HI mass (M HI ) and the diameter of the HI disk (D HI ) defined at a surface density (Σ HI ) of 1 M pc 2 " (R HI = D HI /2) "log D HI = (0.506 ± 0.003) log M HI (3.293 ± 0.009). The rms scatter around the relation is only 0.06 dex (14%). The intercept of (logM HI 2logD HI )=0.5logM HI /D HI 2 indicates a uniform characteristic HI surface density HI,c =4 M HI D 2 H I =5.07 M pc 2 for different galaxies. " 37 Strong correlation between HI mass and stellar mass. Wong, Meurer et al. 2016, MNRAS 38

20 V c R outer HI disk 0.1 pc/myr kpc 39 The SPARC disk galaxy sample? 40

21 Lelli et al. (2016) : The SPARC disk galaxy sample "We collected more than 200 extended H I rotation curves from previous compilations, large surveys, and individual studies (see Section 3.2 for details). This kinematic data set is the result of 30 yr of interferometric H I observations using the Westerbork Synthesis Radio Telescope (WSRT), Very Large Array (VLA), Australia Telescope Compact Array (ATCA), and Giant Metrewave Radio Telescope (GMRT). Subsequently, we searched the Spitzer archive and found useful [3.6] images for 175 galaxies. Most of these objects are part of the Spitzer Survey for Stellar Structure in Galaxies (S 4 G; Sheth et al. 2010). We also used [3.6] images from Schombert & McGaugh (2014b) for low-surface-brightness (LSB) galaxies, which are usually underrepresented in optical catalogs with respect to high-surface-brightness (HSB) spirals (e.g., McGaugh et al. 1995a). SPARC is not a statistically complete or volumelimited sample, but it forms a representative sample of disk galaxies in the nearby universe spanning the widest possible range of properties for galaxies with extended rotation curves. Table 1 lists the main properties of SPARC galaxies." "SPARC spans a broad range in morphologies (S0 to Im/BCD), luminosities ( 10 7 to L e ), effective radii ( 0.3 to 15kpc), effective surface brightnesses ( 5 to 5000 L e pc 2 ), rotation velocities ( 20 to 300 km s 2 ), and gas content (0.01 < M H I /L [3.6] < 10). " "We note that SPARC galaxies are representative of the disk population in the field, nearby groups, and diffuse clusters like Ursa Major (Tully & Verheijen 1997). " 41 Lelli et al. (2016) : The SPARC disk galaxy sample "For most low-mass and LSB galaxies, exponential functions provide a good description of the surface brightness profiles over a broad radial range, but several galaxies show light enhancements/ depressions in the inner parts (similar to optical bands; e.g., Swaters & Balcells 2002; Schombert et al. 2011). As expected, the vast majority of spiral galaxies show deviations from exponential profiles in the inner parts due to bulges, bars, and lenses." 42

22 Lelli et al. (2016) : The SPARC disk galaxy sample "For most low-mass and LSB galaxies, exponential functions provide a good description of the surface brightness profiles over a broad radial range, but several galaxies show light enhancements/ depressions in the inner parts (similar to optical bands; e.g., Swaters & Balcells 2002; Schombert et al. 2011). As expected, the vast majority of spiral galaxies show deviations from exponential profiles in the inner parts due to bulges, bars, and lenses." 43 Galactic disks are exponential disks why? "These observations suggest that exponentials are the generic surface density forms for the full range of two-dimensional galaxy components, and that these profiles extend over a huge range of surface brightness. They must be able to reform promptly after major disturbances, especially in dwarfs, and initially form promptly as judged by their presence in high-redshift galaxies (Fathi et al. 2012). These more recent results greatly stress some older theories for the origin of the exponentials. " --> not understood yet ( since 70 years)! 44

23 Lelli et al. (2016) : The SPARC disk galaxy sample "For most low-mass and LSB galaxies, exponential functions provide a good description of the surface brightness profiles over a broad radial range, but several galaxies show light enhancements/ depressions in the inner parts (similar to optical bands; e.g., Swaters & Balcells 2002; Schombert et al. 2011). As expected, the vast majority of spiral galaxies show deviations from exponential profiles in the inner parts due to bulges, bars, and lenses." 45 Lelli et al. (2016) : The SPARC disk galaxy sample "For most low-mass and LSB galaxies, exponential functions provide a good description of the surface brightness profiles over a broad radial range, but several galaxies show light enhancements/ depressions in the inner parts (similar to optical bands; e.g., Swaters & Balcells 2002; Schombert et al. 2011). As expected, the vast majority of spiral galaxies show deviations from exponential profiles in the inner parts due to bulges, bars, and lenses." 46

24 The SPARC sample 47 The SPARC sample 48

25 The SPARC sample 49 The SPARC sample 50

26 The SPARC sample Lelli et al. (2016) M =0.5L [3.6 µm] log 10 (M HI )=(0.54 ± 0.02)log 10 (L [3.6 µm] )+(3.90 ± 0.23) log 10 (M HI )=(1.87 ± 0.03)log 10 (R HI ) (7.20 ± 0.03) log 10 (R HI )=(0.86 ± 0.04)log 10 (R d )+(0.79 ± 0.02) Compare with the findings by Wang, Koribalski et al. (2016) shown above - do they agree? Thus, if L [3.6 µm] is measured, we can determine the stellar mass, the HI gas mass, the radial disk scale length and the HI radius of any star-forming rotationally supported disk galaxy. 51 END of Lecture 3

Why is the dark-matter approach ill-fated?

Why is the dark-matter approach ill-fated? First PoR Meeting Observatoire astronomique de Strasbourg 21st of September 2015 Pavel Kroupa Helmholtz-Institut fuer Strahlen und Kernphysik (HISKP) Helmholtz