Niels Bohr Institute > Calendar > 2010 > Causal Dynamical Trian...

Causal Dynamical Triangulations, Mid-term colloquium by Laura Gava

In order to obtain a theory of quantum gravity for two-dimensional
spacetimes with Lorentzian signature, Causal Dynamical Triangulations (CDT) sums
over all possible geometries using triangles as "building blocks" while
imposing a causal structure on them. The Hausdorff dimension is found to be
2, contrasting with two-dimensional Euclidean quantum gravity, which has a
fractal dimension of 4. A more general version of CDT englobes topology
changes of space, thus allowing for the creation of baby universes. By
further allowing for the universes to merge, CDT has also been formulated as
a string field theory.

Quantum gravity in two-dimensions can be exactly solved and its tools may be
useful in a theory of quantum gravity of higher dimensions. In this talk, I
will give an overview of the construction of CDT as well as some of its
results.