| Abstract: |
I introduce Group Field Theory (GFT) as a bridging framework for quantum gravity, emphasizing its formal and conceptual relations with different quantum gravity approaches such as string theory, simplicial gravity, and canonical (loop) quantum gravity. I then discuss how semiclassical, continuum physics can be obtained from GFT, touching upon the challenges in defining locality and coarse-graining in quantum gravity and showing how these issues can be solved by making use of the relational strategy. I provide a concrete example of the implementation of such a strategy in GFT and use it to extract cosmological physics. I show that,within the resulting cosmological models, the initial singularity is resolved into a quantum bounce and that cosmological perturbations emerge from the quantum entanglement of the underlying quantum gravity degrees of freedom, with their effective dynamics modified on trans-Planckian scales. Finally, I show that quantum gravitational interactions alone can produce cosmic acceleration, leading to the emergence of evolving dark energy as well as a slow-roll inflationary phase. I conclude by providing an outlook on future research directions.
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