Description
chair: Anna Pachoł, Tomasz Pawłowski
What happens at the evaporation of a black of a black hole is not only still unclear, but also -- contrary to what is sometimes claimed -- relevant for the issue of unitarity in blackhole physics. I illustrate what we know about this physics. I show that the problem breaks into three distinct processes, to some extent independent: the quantum physics of the matter reaching the black hole...
Causal Dynamical Triangulations (CDT) is a background independent approach to quantum gravity which introduces a lattice regularization. The framework uses only geometric invariants without referring to any coordinate system.
One of its features is the ability to control the topology of the Universe. The introduction of toroidal spatial topology allows for a definition of hypersurfaces which...
A space of quantum states and an algebra of quantum observables are constructed over the set of all metrics of arbitrary but fixed signature, defined on a manifold. The construction is diffeomorphism invariant, and unique up to natural isomorphisms.
In this talk, I will present the first construction of the theory of quantum gravity completely free of UV divergences. I will show the successful construction in the framework of quantum field theory of gravitational interactions. Moreover, I will relate the enhanced symmetry properties of this theory with fixed points of RG flow and ensuing quantum conformal invariance. The implications for...
The spectral dimension is one of definitions of the effective dimensionality of spacetime that is commonly applied to characterize quantum gravity models. A quite universal prediction is the dimensional reduction to 2 in the UV regime. The notion of spectral dimension can be seen as arising from properties of either a (fictitious) diffusion process or spectral geometry. In the latter context,...
The interior of a Schwarzschild black hole is quantized by the method of loop quantum gravity. The Hamiltonian constraint is solved and the physical Hilbert space is obtained in the model. The properties of a Dirac observable corresponding to the Arnowitt-Deser-Misner mass of the Schwarzschild black hole are studied by both analytical and numerical techniques. It turns out that zero is not in...
I will present quantum model of the dynamics underlying the Belinski-Khalatnikov-Lifshitz (BKL) scenario. The classical BKL scenario concerns generic singularity of general relativity. The quantum BKL scenario indicates that the gravitational singularity can be avoided by a quantum bounce. The latter presents a unitary evolution of considered gravitational system. It is fairly probable that...
It is well-known that quantum groups are relevant to describe the quantum regime of 3d gravity. They encode a deformation of the gauge symmetries (Lorentz symmetries) parametrized by the value of the cosmological constant. Such deformation might be perplexing from a classical picture since the action is defined in terms of plain/undeformed gauge symmetry. I would like to present here a novel...
