The strong cosmic censorship conjecture states that black hole spacetimes cannot be continued beyond their inner horizon due to the divergence of local observables, such as the stress-energy tensor of a classical or quantum scalar field, at that horizon. In the case of a spherically symmetric, charged black hole, numerical and analytical studies indicate, that this conjecture is violated...
Many results in general relativity rely crucially on classical energy conditions inflicted on the stress-energy tensor. Quantum matter, however, violates these conditions since its energy density can become arbitrarily negative at a point. Nonetheless quantum matter should have some reminiscent notion of stability, which can be captured by the so-called quantum (weak) energy inequalities...
The Einstein-Palatini formulation of gravity treats the metric and the connection as independent degrees of freedom. The most general extension on the level of the Einstein-Hilbert action equips the connection with a U(1)-symmetric vector field as an addition to the conventional Levi-Cevita connection. Making a scale-dependant analysis within the Asymptotic Safety scenario of quantum gravity...
Multi-messenger observations of binary neutron star mergers can provide essential information on the properties of the nuclear equation of state of these compact objects. We perform Bayesian inference on GW170817 and its kilonova counterpart AT2017gfo, constraining the radius of a neutron star of 1.4 M⊙ to 12.2±0.5 km (1σ level). Furthermore, we show how post-merger gravitational-waves can...
The outcome of a binary neutron star merger dominantly depends on the total mass of the system and the equation of state describing the matter. However, the mass ratio also influences the postmerger evolution, in particular, whether there is a prompt or delayed collapse. Furthermore, the mass ratio influences which fraction of the initial baryonic mass ends up in a disc around a so formed...
Though General Relativity has been successfully tested so far, concepts such as dark energy and string theory suggest the need of modifying it. Scalar-tensor theory is one of the most popular alternatives discussed. The key motivation for looking at the ones with massive fields is that they are far less constrained by binary pulsar observations, in contrast to the massless case. In this talk,...
Topological systems of non-interacting electrons may be forced by their topological nature to have a gapless spectrum. As two examples, Integer quantum Hall states and topological insulators must carry gapless edge states, which allow them to carry current. Whether interaction between the electrons may turn a gapless conductor into a fully gapped insulator depends on the case at hand, with a...