|  Causal Dynamical Triangulations | 
In General
  > s.a. Triangulations; Wilson Loops.
  * Idea: An approach to quantum
    gravity that takes inspiration from lattice field theory and statistical mechanics;
    The difference with respect to other dynamical triangulations is that the geometry
    is Lorentzian and one considers only triangulations admitting regular foliations.
  * Results: Both in 3 and 4 spacetime
    dimensions a geometric phase has been identified in which the large scale properties
    of the average spacetime are sufficiently classical, and spacetime emerges dynamically
    from the sum over histories.
  @ Reviews: Ambjørn et al CP(06)ht/05,
    in(09)ht/06;
    Alpert SA(07)feb; Loll CQG(08)-a0711;
    Ambjørn et al SA(08)jul,
    LNP(10)-a0906,
    in(12)-a1004;
    Forcier a1109-MS [introduction];
    Ambjørn et al PRP(12)-a1203 [and UV fixed point],
    a1302-ch,
    a1302-conf;
    Cooperman FP(15)-a1410 [concise yet comprehensive introduction];
    Ambjørn et al a1509-MG14 [recent results];
    Glaser & Loll CR(17)-a1703 [and cosmology];
    Loll CQG(20)-a1905.
  @ General references: Markopoulou & Smolin NPB(06)ht/04 [varying lapse];
    Benedetti PhD(07)-a0707 [analytical];
    Zohren PhD(08)-a0905;
    Durhuus et al JSP(10)-a0908 [spectral dimension];
    Ambjørn et al PLB(10)-a1001 [geometry];
    Kommu CQG(12)-a1110 [independent verification of results];
    Giasemidis PhD(13)-a1310 [graph toy models and spectral dimcnsion];
    Glaser a1409-PhD;
    Clemente et al PRD(19)-a1903,
    a1912-proc [spectral methods].
  @ Renormalization:
    Ambjørn et al CQG(14)-a1405
    & CQG+ [group flow];
    Cooperman GRG(16)-a1406;
    Ambjørn et al a1906 [possible UV fixed point].
  @ Continuum limit: Benedetti et al PRD(07)-a0704 [and Hamiltonian];
    Benedetti & Henson PRD(09)-a0911 [de Sitter space as semiclassical ground state];
    Ambjørn et al NPB(11)-a1102,
    Trzesniewski MS(10)-a1102 [4D];
    Smit JHEP(13)-a1304 [continuum interpretation];
    Cooperman a1604.
  @ Phase structure: Ambjørn et al PRL(11)-a1108 [evidence for a second-order phase transition];
    Ambjørn et al PRD(12)-a1205 [first-order and second-order];
    Ambjørn et al JHEP(15)-a1503 [signature change];
    Coumbe et al JHEP(16)-a1510;
    Ambjørn et al EPJC(17)-a1610;
    Clemente & D'Elia PRD(18)-a1804 [eigenvalues of the Laplace-Beltrami operator];
    Ambjørn et al CQG(19)-a1904 [critical phenomena].
  @ Topology change: Westra PhD-a0810;
    Ambjørn & Budd JPA(13) [generalized causal dynamical triangulations];
    > s.a. topology change.
  @ 2D: Ambjørn & Loll NPB(98)ht [initial idea];
    Ansari & Markopoulou NPB(05)ht [as a spin system];
    Loll et al AIP(06)ht [sum over topologies];
    Zohren MS(05)ht/06 [analytic results, rev];
    Benedetti & Loll GRG(07)gq/06 [counting graphs, and matter behavior];
    Ambjørn et al JHEP(07)-a0709 [with partial lifting of causality constraint];
    Ambjørn et al APPB-a0911-ln [survey];
    Atkin PhD(11)-a1111;
    Fuji et al PLB(11) [with extended interactions];
    Ambjørn PLB(12) [and baby universes];
    Ambjørn & Ipsen PLB(13) [universality];
    Ambjørn et al MPLA(15)-a1412 [coupled to scalar fields, spectral dimension];
    Ambjørn & Watabiki PLB(15)-a1505 [string field theory model];
    Ambjørn et al a2003 [zero-temperature criticality];
    > s.a. cosmological constant problem.
  @ 3D: Ambjørn et al NPB(01)ht [and 4D];
    Ambjørn et al NPPS(02)hl;
    Dittrich & Loll PRD(02);
    Konopka PRD(06)ht/05 [varying lapse];
    Sachs a1110 [power spectrum of quantum fluctuations];
    Cooperman & Miller CQG(14)-a1305 [transition amplitudes];
    Budd & Loll PRD(13)-a1305 [for torus topology];
    Bernabei & Thaler a1412 [central limit theorem];
    Cooperman et al CQG(17)-a1610 [Lorentzian vs Euclidean de Sitter space];
    Cooperman CQG(18)-a1711 [spectral dimension];
    Durhuus & Jonsson a1712 [structure of spatial slices].
  @ 3D, without a preferred foliation: Jordan & Loll PLB(13)-a1305;
    Jordan & Loll PRD(13)-a1307 [emergence of de Sitter space].
  @ 4D: Ambjørn et al PRL(04)ht;
    Ambjørn et al PRL(05)ht [small-scale spectral dimension],
    PRL(08)-a0712,
    PRD(08)-a0807,
    PLB(10)-a1001 [quantum de Sitter universe];
    Durhuus & Jonsson CMP(15)-a1408 [bound on the number of causal triangulations];
    Gizbert-Studnicki PhD(14)-a1510 [effective action];
    Gizbert-Studnicki APPB-a1704 [phase structure];
    Ambjørn et al a2007 [dynamical fractal geometries].
  @ 4D, toroidal topology: Ambjørn et al PRD(16)-a1604 [impact of spatial topology];
    Ambjørn et al NPB(17)-a1705,
    JHEP(18)-a1802;
    Gizbert-Studnicki APPB-a1912-conf [phase transitions];
    Ambjørn et al a2103 [overview].
  @ 4D, transfer-matrix approach:
    Görlich PhD(10)-a1111,
    a1302-proc;
    Ambjørn et al JHEP(14)-a1403.
  @ Related topics: Sisko et al a1201 [uniform infinite causal triangulations];
    Giasemidis et al JPA(12),
    a1209-proc
      [random multigraphs, random walk and scale-dependent spectral dimension];
    Cooperman PRD(14)-a1410 [scale-dependent homogeneity measures];
    > s.a. spacetime dimensionality [reduction].
Models, Phenomenology > s.a. minisuperspace
  quantum cosmology; quantum gravity and cosmology.
  * Cosmology: CDT predicts that the
    (renormalized) cosmological constant is positive, but not a specific value for it.
  @ References: Mielczarek EPL(17)-a1503 [dispersion relations and cosmological perturbations],
a1512-MG14.
Variations, Related Theories and Generalized Settings
  @ General references: Freedman a1008
      [for a formal chain of combinatorial spacetimes without predetermined dimensionality];
    Sisko et al JSP(13)-a1203 [growth process for causal triangulations by elementary moves].
  @ Relationship with asymptotic safety: Ambjørn et al LNP-a1007 [and entropic gravity];
    Coumbe & Jurkiewicz JHEP(15)-a1411 [from dimensional reduction].
  @ Relationship with Hořava-Lifshitz gravity:
    Ambjørn et al PLB(10)-a1002;
    Anderson et al PRD(12)-a1111;
    Ambjørn et al PLB(13)-a1302 [2D CDT is 2D Hořava-Lifshitz quantum gravity];
    Ambjørn et al IJMPD(13)-a1305;
    Benedetti & Henson CQG(15)-a1410
    + CQG+ [spacetime condensation];
    > s.a. hořava-lifshitz gravity.
  @ And other approaches / models:
    Ambjørn et al PLB(08),
    Benedetti & Henson PLB(09)-a0812 [and matrix models];
    Ambjørn et al JPCS(10)-a1004 [and stochastic quantization];
    Kawabe PTEP(16)-a1604 [generalized cdt of tensor model];
    > s.a. Dimer Models; Potts Model [coupled to gravity].
  @ Variations: Khavkine et al CQG(10)-a1002 [coupled to a pointlike mass];
    Atkin & Zohren JHEP(12) [multi-critical CDT, quantum geometry];
    Loll & Ruijl PRD(15)-a1507 [locally causal dynamical triangulations];
    Vojinović PRD(16)-a1506 [in the spincube model];
    Ambjørn et al a2105 with [scalar fields];
    > s.a. ising model.
 main page
  – abbreviations
  – journals – comments
  – other sites – acknowledgements
  send feedback and suggestions to bombelli at olemiss.edu – modified 23 may 2021