7 papers
Light propagation and intensity transport in metric-affine geometry
Antonio De Felice, Lavinia Heisenberg, Gonzalo J. Olmo +1
We study electromagnetic wave propagation in metric--affine geometries, where torsion and non-metricity may be present and the coupling between electromagnetism and spacetime is no…
Cosmology from asymptotically safe Proca theories
Carlos Pastor-Marcos, Lavinia Heisenberg, Álvaro Pastor-Gutiérrez +2
Effective field theories for cosmology offer a powerful framework to investigate the dynamics of space--time and address longstanding open puzzles. In this work, we initiate a prog…
Autoparallels and the Inverse Problem of the Calculus of Variations
Lavinia Heisenberg
We prove that autoparallel curves associated with a torsion-free but not necessarily metric-compatible affine connection can be derived from an action principle. We explicitly cons…
A Re-Examination Of Foundational Elements Of Cosmology
Lavinia Heisenberg
This paper undertakes a conceptual re-examination of several foundational elements of cosmology through the lens of spacetime symmetries. A new derivation of the Friedmann-Lemaître…
Neutron stars in gravity
Lavinia Heisenberg, Carlos Pastor-Marcos
We investigate the challenges of constructing neutron star (NS) solutions in gravity, highlighting the importance of treating the affine connection as an active, dy…
Counting Degrees of Freedom: A Method Applicable from Scalars to f(Q) Gravity and Beyond
Lavinia Heisenberg
We present a clear, step-by-step method for counting degrees of freedom and identifying constraints in general field theories. This approach, grounded in the works of Einstein, Hil…
To the Problem of Cosmic Expansion in Massive Gravity
Lavinia Heisenberg, Alessandro Longo, Giovanni Tambalo +1
We consider evolving, spatially flat isotropic and homogeneous (FLRW) cosmologies in ghost-free (dRGT) massive gravity. In this theory, no dynamical flat FLRW background exists if…