Galaxy Distribution and Motions  

In General > s.a. cosmological principle [homogeneity, isotropy]; matter distribution in cosmology [including cosmic web].
* Distance determination: For nearby galaxies, variable stars like Cepheids; For other ones, (type Ia) supernovae and Hubble's law.
* 1908: C V I Charlier proposed a hierarchical model of galaxy distribution.
* 1986: Bubble structure observed from survey of 1100 galaxies near the galactic north pole, with visible light, and 2700 galaxies in another region, with 21 cm radiation; The size of bubbles is as large as 50 Mpc; These could be formed by first generation explosions (quasars, supernovae?).
* 1989: A galaxy in formation seen at 65 Mly, 10 times larger than the Milky Way.
* 1994: Galaxies as faint as magnitude 27 (blue) can be seen with CCDs.
* 1996: Youthful galaxies studied at z ~ 3.5, 15% of present time, when galaxy formation was under way.
* 1998: 0140+326RD1 at z = 5.34, other at z = 6.68 [this must have not been confirmed, see 2002].
* 1999: Information on \(5 \times 10^7\) galaxies collected by Digital Palomar Sky Survey; The most numerous ones are dwarves; About 104 redshifts have been measured (notice that z space is not identical with real space, because of virialization).
* 2002: Most distant galaxy so far (not a quasar) seen at \(z\) = 6.56, or 15.5 Gly, using the Abell 370 cluster as lens.
* 2006: First observational evidence that galaxies are not randomly oriented, but follow the dark-matter pattern [@ news sr(06)apr].
* 2009: Large-volume cosmological surveys reveal that galaxies are distributed along filaments, connected to form a percolating network, the cosmic web.
@ Large-scale structure: de Lapparent et al ApJL(86) [bubble picture]; Coles Nat(90)aug; Hendry & Simmons ViA(95)ap; Pietronero et al ap/95-proc; Einasto NAR(01)ap/00, ap/00-MG9; Nabokov & Baryshev Astr(10)-a1004, Astr(10)-a1004 [at Gpc scales]; Scargle et al ApJ(17)-a1510 [Fourier transform].
@ Books, reviews: Rowan-Robinson 85; Dressler 94 [I]; Saslaw 00; Lahav & Soto LRR(04) [redshift surveys].
@ Rotation alignment: Lee ApJL(04)ap; Longo ap/07, a0812, a0904, a0908-wd [handedness and preferred axis]; Hahn et al MNRAS(10)-a1002 [large-scale orientations]; Aryal RAA(11)-a1010 [winding around the Local Supercluster]; Lee ApJ(11)-a1011 [high statistical significance]; Shamir PLB(12) [handedness asymmetry at z < 0.3]; Blazek et al JCAP(15)-a1504, a1504-proc [tidal alignment]; Joachimi et al SSR(15)-a1504 [rev]; > s.a. galaxies [rotation].
@ Related topics: Kraan-Korteweg et al ap/98-proc [on other side of Milky Way]; Sylos Labini A&A(10)-a1007 [gravitational field and large-scale flows]; Finkelstein PASA(16)-a1511 [searches for galaxies at z > 6]; > s.a. higher-dimensional gravity.
> Online resources: The Extragalactic Distance Database site.

Groups, Clusters, Superclusters, Filaments, Sheets > s.a. cosmological constant; local group; types of galaxies.
* Difference: Galaxy groups differ from clusters primarily by way of their lower masses, \(M\sim10^{14}\,M_\odot\) vs. \(M\sim10^{15}\,M_\odot\).
* Largest structure: In 1999, a filament at least 4 × 108 ly long, perhaps \(10^9\) ly, in Aquarius, with at least \(10^5\) galaxies.
* Assembly bias: The fact that the distribution of galaxies and galaxy clusters depends both on the total mass of the objects and on the assembly history.
@ General references: Abdullah et al MNRAS(11)-a1408 [nearby, dynamical properties]; Sepp & Gramann IJGMP(14)-a1309-proc [rev]; Sepp & Gramann IJGMP(14) [rev]; Holanda & Alcaniz APP(15)-a1404 [cosmological constraints].
@ Catalogs, surveys: Bernardi ap/03-in [SDSS]; Lahav & Suto LRR(04) [and cosmology]; Strauss SA(04)feb; Driver et al MNRAS(05)ap [MGC]; Zhan et al ApJ(06)ap/05 [future, applications]; Padmanabhan et al MNRAS(07)ap/06 [SDSS]; SubbaRao & Aragón-Calvo pw(08)dec [maps]; Scranton et al a0902-rp, Myers a0903-rp [the case for deep, wide surveys]; Bonvin & Durrer PRD(11)-a1105 [what is really measured]; Percival a1312-ln; Bland-Hawthorn IAU(15)-a1410 [Hector: integral field spectroscopy of 100,000 galaxies].
@ Description and detection: Pimbblet PASA(05)ap [filaments]; Noh & Lee ap/06/ApJL [local pancakes]; Simon et al ApJ(06)ap [fundamental line for disk galaxies]; Sarkar & Bharadwaj MNRAS(09)-a0812 [local dimension]; Shandarin JCAP(09)-a0812 [great walls]; Makarov & Karachentsev a0908-proc [groups in the Local Supercluster]; Gay et al MNRAS(10)-a0910 [filamentary environment]; Einasto et al A&A(10)-a1007 [Sloan Great Wall]; news ps(10)oct [most massive cluster known seen in cmb distorsions, with 800 trillion solar masses]; Capozzi et al MNRAS(12)-a1207 [Shakhbazyan groups]; Kovetz & Kamionkowski PRD(13)-a1210 [masses, using 21-cm radiation lensing]; Balaguera-Antolínez A&A(14)-a1306 [spatial distribution of galaxy clusters and scaling relations]; Kovács & García-Bellido MNRAS(16)-a1511 [Cold Spot, Eridanus Supervoid, and Great Walls].
@ Dynamics and implications: Jackson MNRAS(72)-a0810 [velocity dispersion and "Fingers-of-God" effect]; Bahcall ap/98-ln; Schindler ap/00-conf, ap/01-conf [simulations], ap/01-conf [rev]; Reed et al MNRAS(09)-a0804 [first galaxies, simulations]; Rossetti et al A&A(11)-a1106 [cool core and non-cool core clusters]; Kravtsov & Borgani ARAA(12)-a1205 [clusters, formation]; Ota a1211-conf [particle acceleration, gas heating]; Guo et al ApJ(15)-a1403 [galaxies in filaments have more satellites]; Yoo CQG(14)-a1409 [galaxy clustering, relativistic effects]; Miyatake et al PRL(16) + Dalal Phy(16) [evidence for assembly bias]; Rudnick PT(19)jan [interactions].
@ Specific clusters: Biviano ap/97-conf [properties of the Coma cluster]; Sorce et al MNRAS(16)-a1605 [Virgo cluster, formation].
@ Related topics: Brosch a0906-conf [truly isolated galaxies]; Cavaliere & Lapi PRP(13) [intracluster plasma].
> Catalogs and surveys: see the Abell Catalog of galaxy clusters; Sloan Digital Sky Survey of galaxies (and Wikipedia page); 2dF Galaxy Redshift Survey.
> Related topics: see galaxies [velocity fields]; phenomenology of higher-order gravity [cluster density profiles].

Voids and Motions > s.a. cosmic acceleration and inhomogeneities; Intergalactic Matter.
* Bulk flow: A (scale-dependent) volume average of the peculiar velocities of galaxies, and a useful probe of the mass distribution on large scales.
@ Local Void: Iwata et al ASP-ap/05; Tully IAU(07)-a0708 [evacuation, really empty]; Iwata & Chamaraux A&A(11)-a1105; Whitbourn & Shanks a1307-MNRAS [from galaxy counts and redshifts]; Xie et al MNRAS(14)-a1401 [statistical analysis]; Cusin et al JCAP(17)-a1609 [lensing signature].
@ General references: Peebles ApJ(01)ap; Serpico ap/07-proc; Tikhonov AL(07)-a0707; von Benda-Beckmann & Mueller a0710/MNRAS; Park & Lee PRL(07) [ellipticity and cosmology]; Gaite a0802; Foster & Nelson ApJ(09)-a0904 [SDSS, void catalog]; Slosar & White JCAP(09) [alignment of nearby-galaxy spins]; Giovanelli a0909 [Void Phenomenon]; Gaite JCAP(09)-a0911 [statistics]; van de Weygaert & Platen MPLA(11)-a0912-conf, et al a0912-in [rev]; Aragón-Calvo et al MNRAS(10)-a1002 [hierarchical identification]; Einasto et al A&A(11)-a1105 [understanding void formation]; Thompson & Gregory a1109 [historical view]; Alpaslan et al MNRAS(14)-a1401 [filaments of galaxies detected within voids]; Hamaus et al PRL(14) [universal density profile]; Szapudi et al MNRAS(14)-a1405 [and the cmb cold spot]; Hamaus et al a1409-IAU [void statistics]; Tavasoli et al ApJL(15)-a1410 [properties of galaxies residing in voids]; Nadathur & Hotchkiss MNRAS(15)-a1504 [void finders and theoretical models]; Pycke & Russell ApJ(16)-a1602 [statistical perspective]; > s.a. cmb anisotropy [Cold Spot and supervoid].
@ And tests of fundamental physics: Triay & Fliche PTPS(08)-a0801 [voids and the cosmological constant]; Cai & Padilla a1410-IAU [and gravity tests]; Pisani et al PRD(15) [void counts and the dark energy equation of state]; > s.a. cosmological tests of general relativity.
@ Dynamics, and bulk flows: Yoo et al PRD(09)-a0907; Ma et al PRD(11)-a1010; Bland-Hawthorn & Sharma a1410-IAU [and void asymmetries in the cosmic web]; Padilla a1410-IAU; Nusser MNRAS(16)-a1508 [comparing several estimators]; Lambas et al MNRAS(16)-a1510 [bulk motions]; Kumar et al a1512 [bulk flows and gravitational potential wells]; Andersen et al MNRAS(16)-a1609 [peculiar velocities and cosmological models].
@ Related topics: Pavlovski et al MNRAS(08)-a0709, a0709/MNRAS [buoyant bubbles].

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