FAU^2 Workshop on quantum gravity across scales: from physics at the Planck scale to effective theories

Session

Session 5

22 May 2025, 13:30

ECAP Laboratory Building

59. Quantum reference frames and their application in quantum gravity

Philipp Höhn

22/05/2025, 13:30

invited talk

Quantum reference frames are a universal tool for dealing with symmetries in quantum systems. They are the means to describe a quantum system "from the inside" and key for completing the relational paradigm. As such, they naturally arise in quantum gravity whenever we build invariant observables. In this talk, I will review quantum reference frames and some of their applications to questions...

54. Effective actions and observables

Kevin Falls

22/05/2025, 14:10

invited talk

In quantum gravity, there is a huge freedom in constructing effective actions since they depend on a choice of gauge and field parameterisation. In this talk, I will discuss an approach to constructing effective actions for gauge-invariant fields. Moreover, I will discuss recent progress in understanding when two effective actions are physically equivalent. Some consequences for quantum...

61. Hamiltonian renormalisation of the U(1)^3 model for 3+1 quantum gravity

Melissa Rodriguez Zarate

22/05/2025, 14:50

contributed talk

64. What triangulations at criticality in TGFT?

Johannes Thürigen

22/05/2025, 15:20

contributed talk

One way to obtain a continuum limit of Spin Foams is to use a field-theory partitition function to generate triangulations as Feynman diagrams and tune to criticality. This philosophy works well for Matrix-Models with a limit to 2D Quantum Gravity and these have a well established generalization to Tensorial Group Field Theory (TGFT) generating 4D triangulations. However, finding a 4D...

63. Dynamics of semiclassical states in the single-vertex model of quantum-reduced loop gravity

Ilkka Mäkinen

22/05/2025, 15:50

contributed talk

62. Computing the graph-changing dynamics of loop quantum gravity

Thiago Lucena de Macedo Guedes

22/05/2025, 16:20

contributed talk