Caustics are regions of high intensity created generically by the natural focusing of waves. Some examples include optical rainbows, gravitational lensing, sonic booms, and even rouge waves. The intensity at a caustic is singular in the classical ray theory, but can be smoothed out by taking into account wave interference effects. Caustics are universally described by the mathematical theory...
Despite its success in explaining the large-scale evolution of the universe, standard big bang cosmology has many unsolved problems. For example, it cannot explain why the universe is homogeneous and flat to the degree of precision we observe today. Moreover, as one goes back to the time of the big bang, the universe’s energy density is expected to reach infinity, leading to an initial...
In his seminal work, Bekenstein conjectured that quantum-gravitational black holes possess a discrete mass spectrum, due to quantum fluctuations of the horizon area. The existence of black holes with quantized mass implies the possibility of considering superposition states of a black hole with different masses. Here we construct a spacetime generated by a BTZ black hole in a superposition of...
The classical black hole is one of the most extreme and scientifically rich products of classical
general relativity. However, it has predictions which still leave some uncomfortable; these primarily being
the nature of the event horizon and the mass singularity. This has led to the development of alternative
black hole ‘mimicking’ models which correct for these singularities and retain...
