Pseudo-topological transitions in 2D gravity models coupled to massless scalar fields

TY - JOUR

T1 - Pseudo-topological transitions in 2D gravity models coupled to massless scalar fields

AU - Ambjørn, Jan

AU - Gorlich, A. T.

AU - Jurkiewicz, J.

AU - Zhang, H-G.

PY - 2012/10/11

Y1 - 2012/10/11

N2 - We study the geometries generated by two-dimensional causal dynamical triangulations (CDT) coupled to d massless scalar fields. Using methods similar to those used to study four-dimensional CDT we show that there exists a c=1 "barrier", analogous to the c=1 barrier encountered in non-critical string theory, only the CDT transition is easier to be detected numerically. For d≤1 we observe time-translation invariance and geometries entirely governed by quantum fluctuations around the uniform toroidal topology put in by hand. For d>1 the effective average geometry is no longer toroidal but "semiclassical" and spherical with Hausdorff dimension d H=3. In the d>1 sector we study the time dependence of the semiclassical spatial volume distribution and show that the observed behavior is described by an effective mini-superspace action analogous to the actions found in the de Sitter phase of three- and four-dimensional pure CDT simulations and in the three-dimensional CDT-like Hořava-Lifshitz models.

AB - We study the geometries generated by two-dimensional causal dynamical triangulations (CDT) coupled to d massless scalar fields. Using methods similar to those used to study four-dimensional CDT we show that there exists a c=1 "barrier", analogous to the c=1 barrier encountered in non-critical string theory, only the CDT transition is easier to be detected numerically. For d≤1 we observe time-translation invariance and geometries entirely governed by quantum fluctuations around the uniform toroidal topology put in by hand. For d>1 the effective average geometry is no longer toroidal but "semiclassical" and spherical with Hausdorff dimension d H=3. In the d>1 sector we study the time dependence of the semiclassical spatial volume distribution and show that the observed behavior is described by an effective mini-superspace action analogous to the actions found in the de Sitter phase of three- and four-dimensional pure CDT simulations and in the three-dimensional CDT-like Hořava-Lifshitz models.

U2 - 10.1016/j.nuclphysb.2012.05.024

DO - 10.1016/j.nuclphysb.2012.05.024

M3 - Journal article

SN - 0550-3213

VL - 863

SP - 421

EP - 434

JO - Nuclear Physics, Section B

JF - Nuclear Physics, Section B

IS - 2

ER -