Steffen Gielen

Dr. Steffen Gielen is a Royal Society University Research Fellow at the School of Mathematical and Physical Sciences, University of Sheffield. His research focuses on quantum gravity, cosmology, and the application of group field theory to understand fundamental spacetime structures and singularities. Gielen explores topics such as black hole singularity resolution, quantum cosmology, and the interplay between unitarity and gravitational dynamics.

His work integrates advanced mathematical frameworks (e.g., unimodular gravity, Plebański formalism) with quantum field theory techniques to address unresolved questions in early universe physics and black hole physics. Gielen's contributions include studies on metric reconstruction in group field theory, low-curvature quantum corrections, and the role of Gaussian states in cosmological models.

Key research areas include quantum resolution of cosmological and black hole singularities, the nature of the cosmological constant, and the application of relational dynamics in quantum gravity. His findings have implications for reconciling general relativity with quantum mechanics at a foundational level.

• Awards: Royal Society University Research Fellow (2025–present)

Gielen’s work often involves collaborations on quantum gravity phenomenology, with a focus on group field theory condensates as a tool for cosmological modeling. He contributes to theoretical advancements in understanding spacetime geometry’s quantum origins and its implications for observable cosmological phenomena.