Modern Cosmology  

General Principles, Status, and Issues > s.a. anthropic principle; cosmological constant; holography; references [including conceptual aspects].
* Idea: The study of the properties of the universe as a whole (observations of the matter and radiation content, distribution and evolution, as well as other geometry, topology and dynamics of the spacetime itself), including the early universe.
* Steps, status: 1929, Cosmology becomes a science, based on observation, with Hubble's observation of the expansion of the universe, and its predictions are subject to testing; Proposal of hot Big Bang Theory (the name was first used jokingly by Fred Hoyle in a 1949 BBC broadcast); 1965, Observation of the cmb; 1992, First COBE results on anisotropy; 1997, First evidence that the expansion is accelerating, concept of dark energy; 2003, Emergence of "precision cosmology" with the first WMAP results; 2009, The dominant source of uncertainty in many observations will soon be cosmic variance as opposed to observational noise; 2013, Discrepancy between global (cmb) and local measurements of the Hubble constant and age of the Universe; 2014, Detection of B-mode polarization at angular scales of a few degrees by the BICEP2 cmb telescope.
* Central dogma: The same laws of physics we can test here on Earth apply everywhere in the universe.
@ Cosmography: [kinematics of cosmology] Visser GRG(05)gq/04-proc; Capozziello et al PRD(08).

blue bullet Models: see cosmological models; cosmological principle; multiverse cosmology; numerical general relativity; quantum cosmology.
blue bullet Observations: see cosmic microwave background; large-scale geometry and topology; matter content; observational cosmology [including age].

Other Aspects > s.a. entropy; gravitational thermodynamics; Rigidity; rotation; Superfluids.
* Cosmic coincidence problem: The fact that the densities of vacuum energy and matter are nearly equal today.
* Measure problem: The question of how to assign normalized probabilities to observations; Probabilities are often invoked, e.g., in the context of inflation, but problems arise for various reasons, from more formal ones to the fact that such a large universe may have many observations occurring at many different spacetime locations.
@ Statistics, number counts: Colombi et al MNRAS(00)ap/99; Szapudi et al MNRAS(00)ap/99, MNRAS(99)ap/99; > s.a. galaxy distribution.
@ Beginning and initial singularity: Narlikar PhSc(92)sep; Bogdanov & Bogdanov CQG(01) [!!!]; Vaas bdw(04)phy [lqg]; Szydłowski et al PRD(05) [vs bounce, test]; Grøn EJP(06) [and spatially infinite universe]; Ashtekar phy/06-conf [in quantum gravity]; Frampton a0704-book [I, re beginning and end]; Stenger Philo(06)-a0710 [model]; Berman IJTP(09) [not there]; Craps a1001-conf [intro, and AdS/cft correspondence]; Ashtekar AIP(10)-a1005 [and lqc]; Fujimoto a1103 [philosophical and mathematical]; Adler a1107 [cosmogenesis and spatial flatness]; Brustein & Kupferman HPLS-a1202-conf [the creation according to science]; Mithani & Vilenkin a1204-proc, response Susskind a1204 [on scenarios with no initial singularity]; Penrose FP(14) [conformal cyclic cosmology]; > s.a. arrow of time; boundary conditions in quantum cosmology; history [entropic creation argument]; quantum-gravity phenomenology; quantum cosmology; singularities.
@ Complexity and order: Layzer 89 [I-II]; Hu in(88)gq/95; Parker 96 [I]; Kunz et al PRD(06) [and parameters]; > s.a. complexity.
@ Local vs global physics: Ellis IJMPA(02)gq/01; Ellis & Stoeger MNRAS(09)-a1001 [local cosmic domain and effective causal limits]; > s.a. arrow of time; Birkhoff's Theorem; expansion rate [local effects]; mach's principle; Olbers' Paradox; relativistic cosmology.
@ Coincidences, tuning, naturality: & Hoyle; Carter pr(67)-a0710 [foundation for anthropic principle]; Griest PRD(02) [proposal]; Rees in(03)ap/04; Carroll Nat(06)apr-ht/05; França PLB(06), Funkhouser PRS(06), PRS(08)phy/06 [proposals]; del Campo et al PRD(08)-a0806; Barreira & Avelino PRD(11)-a1103 [anthropic vs cosmological solutions]; Sivanandam PRD(13)-a1203 [coincidence is not a problem, just an artifact of anthropic selection]; Carroll a1406-in [fine tuning].
@ The measure problem: Page JCAP(11)-a1011; Schiffrin & Wald PRD(12)-a1202.
> Pre-big-bang cosmology: see cmb anisotropy; loop quantum cosmology; string phenomenology.

The Future of the Universe > s.a. Big Crunch; Big Trip; civilizations [including Doomsday Argument]; cosmological models.
* Possibilities: If the cosmic energy density will remain constant or strictly increase in the future, the possible fates are:
- Constant expansion rate: The Hubble parameter H(t) = constant, for example if the energy density is dominated by a cosmological constant.
- Pseudo-rip: An intermediate case in which H(t) goes to a constant as time goes to infinity.
- Little rip: H(t) goes to infinity as time goes to infinity.
- Big rip: H(t) goes to infinity at a finite time and eventually all local structure will be ripped apart by the expansion, for example in the case of phantom energy.
* Matter and radiation: 2007, Krauss & Scherrer predict matter energy density will keep dominating radiation energy density.
@ General references: Davies 94 [I]; Krauss & Turner GRG(99); Krauss & Starkman SA(99)nov [and life]; Starobinsky G&C(00)ap/99-conf; Goldsmith 00, Barrow et al MNRAS(00)ap [including acceleration]; Avelino et al PLB(01) [and inflation]; Tipler AIP(01)ap; Chiueh & He PRD(02)ap/01 [local structure]; Hoeneisen ap/02; Ćirković AJP(03)feb-ap/02 [eschatology]; Dąbrowski AdP(06)ap-conf; Page PRD(08)ht/06 [future decay]; Nicolson 07; Krauss & Starkman ap/07 [WIMP annihilation]; Carlip JCAP(07)ht [and variation of constants]; Krauss & Scherrer GRG(07)-a0704-GRF [return of static universe], PRD(07) + sr(07)apr [matter domination]; Bose & Majumdar MNRAS(11)-a1010 [future deceleration]; Bousso et al PRD(11)-a1009 [eternal inflation and the end of time]; Lundgren et al a1201 [black hole evaporation and entropy]; Goldsmith SA(12)mar [new phenomena]; Bondarescu et al a1305-MG13.
@ And dark energy: Huterer et al PRD(02)ap; Kallosh et al PRD(02) [supergravity model]; Loeb PRD(02)ap/01; Adams et al IJMPD(03)ap [island universes]; Kallosh & Linde JCAP(03); Page JKPS(06)ht/05 [lower limit 26 Gyr, upper limit exp{1050}–exp{1060} yr]; > s.a. dark energy [including late-time interaction].
@ And astrophysics: Adams & Laughlin RMP(97)ap [evolution of planets, stars, galaxies]; Loeb JCAP(11)-a1102 + news pw(11)feb [Milkomeda and the role of hypervelocity stars]; Lundgren et al a1304 [thermodynamics and supercluster evolution]; Guillochon & Loeb AMSA-a1411 [using hypervelocity stars].
@ Big rip: Caldwell et al PRL(03)ap; González-Díaz PRD(03)ap, PLB(04)ap/03, PLB(06); Frampton & Takahashi APP(04)ap, Frampton ap/04-talk [no dark energy]; Barboza & Lemos GRG(06)gq [and quantum gravity]; Alvarenga et al G&C(10)-a0904 [back-reaction from particle creation]; > s.a. Phantom Field; viscosity.
@ Other scenarios: Faraoni PRD(03)gq [big smash, superquintessence]; Frampton et al PRD(11)-a1106 [little rip], PRD(12)-a1112 [pseudo-rip]; Bouhmadi-López et al IJMPD(15)-a1407 [little sibling of the big rip].

What caused the Big Bang? God divided by zero.

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