Einstein’s field equations in general relativity admit a variety of solutions with spacetime singularities. Numerical relativity has recently revealed the properties of somewhat generic spacetime singularities. It has been found that in a variety of systems self-similar solutions can describe asymptotic or intermediate behaviour of more general solutions. The typical example is the convergence ...

We derive the equations of motion in metric-affine gravity by making use of the conservation laws obtained from Noether’s theorem. The results are given in the form of propagation equations for the multipole decomposition of the matter sources in metric-affine gravity, i.e., the canonical energymomentum current and the hypermomentum current. In particular, the propagation equations allow for a ...

We calculate the D-instanton corrections (with all D-instanton numbers) to the quantum moduli space metric of a single matter hypermultiplet with toric isometry, in the effective N=2 supergravity arising in type-IIA superstrings compactified on a CalabiYau (CY) threefold of Hodge number h2,1 = 1. The non-perturbative quaternionic hypermultiplet metric is derived by resolution of a complex orbif...

We derive the equations of motion in metric-affine gravity by making use of the conservation laws obtained from Noether’s theorem. The results are given in the form of propagation equations for the multipole decomposition of the matter sources in metric-affine gravity, i.e., the canonical energymomentum current and the hypermomentum current. In particular, the propagation equations allow for a ...

We derive the equations of motion in metric-affine gravity by making use of the conservation laws obtained from Noether’s theorem. The results are given in the form of propagation equations for the multipole decomposition of the matter sources in metric-affine gravity, i.e., the canonical energymomentum current and the hypermomentum current. In particular, the propagation equations allow for a ...

We examine some peculiarities of the subset of lattice preserving elements in a pseudo-Euclidean group, when the lattice under consideration contains a lightlike vector, or more generally, when the restriction of a pseudo-Euclidean metric to the real linear enveloppe of the lattice is not definite. For the case of a Lorentzian metric, it is shown in detail that the isometry group of the spaceti...

In this article we use the idea of algorithmic complexity (AC) to study various cosmological scenarios, and as a means of quantizing the gravitational interaction. We look at 5D and 7D cosmological models where the Universe begins as a higher dimensional Planck size spacetime which fluctuates between Euclidean and Lorentzian signatures. These fluctuations are governed by the AC of the two diffe...

The recent formulation of locally covariant quantum field theory may open the way towards a background independent perturbative formulation of Quantum Gravity. 1 Problems of perturbative Quantum Gravity In quantum field theory the fields are defined as operator-valued distributions on a given spacetime, and many of their properties, in particular the commutativity at spacetime separated points,...

The strongest evidence for dark energy comes presently from geometric techniques such as the supernova distance-redshift relation. By combining the measured expansion history with the Friedmann equation one determines the energy density and its time evolution, hence the equation of state. Because these methods rely on the Friedmann equation which has not been independently tested it is desirabl...