|  Cosmological Models in General Relativity | 
In General
  > s.a. 3D general relativity; early universe [including
  bounces, cyclic]; gravitation; string phenomenology;
  supergravity.
  * Idea: Based on what we see observationally,
    we need models which are statistically homogeneous and isotropic on large scales.
  @ Isotropic: Starobinsky PLB(80);
    Miritzis et al G&C(00) [Painlevé integrability].
  @ G2:
    van Elst et al CQG(02);
    Carot & Collinge CQG(03) [scalar field, as dynamical system];
    Fernández & González JMP(04) [stiffluid].
  @ Closed models: Lasenby & Doran PRD(05)ap/03 [with inflation];
    Heinzle et al PRD(05)gq/04 [Bianchi IX and Kantowski-Sachs pfluid].
  @ Classification, overviews: Fischer GRG(96);
    Coley gq/99-proc,
    Wainwright & Lim JHDE(05)gq/04 [dynamical systems];
    Barrow PRD(14) [4(1+F)+2S independent functions];
    Leon & Fadragas a1412-book [dynamical systems].
  @ Other models:
    Hayward & Twamley PLA(90) [spatially compact hyperbolic];
    Rendall gq/94 [locally homogeneous];
    Gott & Li PRD(98)ap/97 [self-generating];
    Ellis & van Elst in(99)gq/98 [covariant 3+1];
    van Elst et al PRD(00)gq [discontinuous];
    > s.a. models in cosmology; solutions with matter.
  @ Related topics:
    Tsamis & Woodard PLB(98) [expansion rate];
    Krauss & Turner GRG(99)ap [future];
    > s.a. generalized cosmologies.
Homogeneous and Isotropic
  > s.a. cosmological principle; observational
  cosmology; friedmann equation; FLRW models;
  Milne Universe.
  * Standard model: It is based
    on the cosmological principle, and predicts that the universe has evolved from
    an initial singularity, as a FLRW solution; We do not know whether observations
    lead uniquely to a FLRW model, since observational cosmology is very limited.
  * Successes: It has correctly
    explained the background microwave radiation and the He abundance in the universe.
  * Problems: Flatness, horizon,
    monopole (if one includes particle physics), present value
    nbaryons / nphotons
    = 10−10, singularity, structure formation
    (these are partly initial conditions problems); Small anisotropies in the cmb.
  * Solutions:
    Look for models in the usual theory with special properties (doesn't work);
    Completely different theory (?); Add some other ingredients (Steady State
    cosmology; Universal magnetic field; Cosmology and particle physics,
    including inflation; quantum cosmology).
  * Alternatives: "Small
    universes", philosophically attractive but observationally hard to
    distinguish; > s.a. cosmic topology.
  @ Accelerating: Albrecht & Skordis PRL(00)ap/99;
    Johri PRD(01) [tracker fields];
    Neupane CQG(04)ht/03;
    > s.a. theories of acceleration.
  @ As geodesic motion: Townsend & Wohlfarth CQG(04)ht [+ scalars];
    Elias & Saa PoS-gq/07,
    PRD(07)gq [non-minimal coupling, anisotropic].
  @ Related topics: Aguirre PRD(01)ap [and the anthropic principle];
    > s.a. chaos in gravitation.
Homogeneous, Anisotropic > s.a. bianchi
    models [including Kasner and Mixmaster];
    gödel solution; 
    kantowski-sachs models; perturbations.
  * Isometry group:
    An r (> 3)-parameter group of isometries with spacelike orbits;
    If r > 3 there is an isotropy group; Possibilities are R
    = 6, isotropic, FLRW models; or r = 4, local rotational symmetry.
  @ General references:
    Nilsson et al ApJL(99)ap/99 [metric vs radiation isotropy];
    Lim et al CQG(01)gq/99 [with isotropic cmb];
    Stavrinos et al GRG(08)gq/06 [weak anisotropy].
  @ Rotating:
    Obukhov in(00)ap;
    Chrobok et al PRD(01)gq;
    Carneiro GRG(02)gq/00.
  @ Related topics: Vollick GRG(03)ht/01 [Born-Infeld electrodynamics + cosmological constant];
    Hervik CQG(02)gq [5D];
    > s.a. semiclassical general relativity [isotropization].
Inhomogeneous Models
  > s.a. cosmological acceleration and perturbations;
  information; numerical models.
  * Idea: Slightly
    inhomogeneous models, such as perturbations off FLRW models, are used to
    write down corrections to the Friedmann, equation, verify predictions of
    inflation, and understand light propagation in a stochastic situation;
    Highly inhomogeneous models such as the swiss-cheese models (including
    the Einstein-Straus model) are used to find local effects of the overall
    expansion and other specific issues; Both types can be studied using exact
    solutions as models or approximation methods such as averaging.
  * Other examples: Spherical
    models like the Stephani model and the Lemaître-Tolman-Bondi models,
    hierarchical models.
  @ General references: Ellis in(93);
    Ibáñez & Olasagasti CQG(98) [and isotropization];
    Tanimoto PTP(99)gq [and criticality];
    Buchert GRG(00)gq/99,
    et al PRD(00)ap/99 [effect on average];
    Clarkson et al GRG(03) [and the Copernican principle];
    Berger CQG(04) [local Mixmaster dynamics];
    Ellis CQG(11)-a1103 [significance for cosmology];
    Bolejko et al CQG(11)-a1102 [rev];
    Buchert CQG(11)-a1103 [non-perturbative effects];
    Hellaby & Walters  JCAP(18)-a1708 [observables].
  @ And phenomenology:
    Kantowski et al ap/00 [distance vs z];
    Canfora  & Troisi GRG(04)ap/03 [structure formation];
    Moffat JCAP(05)ap [acceleration and cmb];
    Chuang et al CQG(08) [acceleration];
    Hellaby PoS-a0910 [overview];
    Clarkson & Maartens CQG(10)-a1005 [rev];
    Hellaby JCAP(12)-a1203;
    Mishra et al PRD(12)-a1206 [and type-Ia supernovae];
    Skarke PRD(14)-a1407 [evolution and acceleration, non-perturbative].
  @ N-body models: Clifton CQG(11)-a1005 [without averaging, many equally-spaced masses];
    Clifton et al PRD(12)-a1203 [quantification of backreaction].
  @ Methods and solutions:
    Futamase PRL(88) [clumpy universe];
    Krasiński 97;
    Yasuno et al CQG(01) [from gluing];
    Uggla et al PRD(03)gq  [framework];
    Abdalla & Chirenti PhyA(04) [extremely inhomogeneous];
    Ibáñez & Jhingan PRD(04)gq [renormalization group approach];
    Lim PhD(04)gq [pfluid + cosmological constant];
    Imponente & Montani AIP(06)gq [generic behavior];
    Fernández-Jambrina & González-Romero in(07)-a0904 [non-singular];
    di Teodoro & Villalba IJTP(08) [asymptotic symmetries];
    Ferreira PLB(10)-a1006 [locally anisotropic, expanding];
    Krasiński APPB-a1112-conf [comments on misunderstandings];
    Klinger CQG(16)-a1512 [with no symmetries, singularities and billiards];
    synopsis Phy(16)
      [results of relativistic numerical simulations].
  > Other models: see perturbations
    and  cosmological averaging; generalized FLRW models;
    solutions with matter; Stephani Model;
    Swiss-Cheese Models.
  > Related topics: see Ricci Flow;
    tests of general relativity with light; types
    of spacetimes [cylindrical].
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