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Pre-gauging the cosmological scale factor $a(t)$ does not introduce unphysical degrees of freedom into the exact FLRW classical solution. It seems to lead, however, to a non-dynamical mini superspace. The missing ingredient, a generalised momentum enjoying canonical Dirac (rather than Poisson) brackets with the lapse function $n(t)$, calls for measure scaling which can be realised by means of a scalar field. The latter is essential for establishing a geometrical connection with the 5-dimensional Kaluza-Klein Schwarzschild-deSitter black hole. Contrary to the Hartle-Hawking approach, (i) The $t$-independent wave function $psi(a)$ is traded for an explicit $t$-dependent $psi(n, t)$, (ii) The classical FLRW configuration does play a major role in the structure of the most classical cosmological wave packet, and (iii) The non-singular Euclid/Lorentz crossovers get quantum mechanically smeared.
De Sitter Chern-Simons gravity in D = 1 + 2 spacetime is known to possess an extension with a Barbero-Immirzi like parameter. We find a partial gauge fixing which leaves a compact residual gauge group, namely SU(2). The compacticity of the residual g
We consider a model involving a self-interacting complex scalar field minimally coupled to gravity and emphasize the cylindrically symmetric classical solutions. A general ansatz is performed which transforms the field equations into a system of diff
We extend Derricks theorem to the case of a generic irrotational curved spacetime adopting a strategy similar to the original proof. We show that a static relativistic star made of real scalar fields is never possible regardless of the geometrical pr
Applying the Pomeransky inverse scattering method to the four-dimensional vacuum Einstein equation and using the Levi-Civita solution for a seed, we construct a cylindrically symmetric single-soliton solution. Although the Levi-Civita spacetime gener
We consider the entanglement dynamics between two-level atoms in a rotating black hole background. In our model the two-atom system is envisaged as an open system coupled with a massless scalar field prepared in one of the physical vacuum states of i