57 citations · 234 across the 16 of their papers we have counts for
15 papers · 1 filter
Tilt in quadratic gravity
Waleska P. F. de Medeiros, Matheus J. Lazo, Daniel Müller +1
In this work, tilted source solutions in both Einstein-Hilbert General Relativity (GR) and Quadratic Gravity (QG) for the anisotropic Bianchi V model are addressed. Since the excel…
Initial conditions for Starobinsky Inflation with a positive spatial curvature
Daniel Müller, Alexey Toporensky
We have found numerically initial conditions in the plane leading to a successful Starobinsky inflation in gravity for a isotropic metrics with positive spatial cu…
Probing time orientability of spacetime
N. A. Lemos, D. Müller, M. J. Reboucas
In general relativity, cosmology and quantum field theory, spacetime is assumed to be an orientable manifold endowed with a Lorentz metric that makes it spatially and temporally or…
Probing spatial orientability of Friedmann--Robertson--Walker spatially flat spacetime
N. A. Lemos, D. Müller, M. J. Reboucas
One important global topological property of a spacetime manifold is orientability. It is widely believed that spatial orientability can only be tested by global journeys around th…
Generality of Starobinsky and Higgs inflation in the Jordan frame
Swagat S. Mishra, Daniel Müller, Aleksey V. Toporensky
We revisit the problem of generality of Starobinsky and Higgs inflation. The known results obtained in the Einstein frame are generalized for the case of an arbitrary initial energ…
Anisotropic cosmological solutions in gravity
Daniel Müller, Angelo Ricciardone, Alexei A. Starobinsky +1
In this paper we investigate the past evolution of an anisotropic Bianchi I universe in gravity. Using the dynamical system approach we show that there exists a new two-par…
On stability of the Kasner solution in quadratic gravity
A. Toporensky, D. Müller
We consider dynamics of a flat anisotropic Universe filled by a perfect fluid near a cosmological singularity in quadratic gravity. Two possible regimes are described -- the Kasner…
Bianchi I solutions of effective quadratic gravity
Daniel Müller, Juliano A. de Deus
It is believed that soon after the Planck time, Einstein's general relativity theory should be corrected to an effective quadratic theory. Numerical solutions for the anisotropic g…
Bianchi solutions of quadratic gravity
Juliano A. de Deus, Daniel Müller
It is believed that soon after the Planck time, Einstein's general relativity theory should be corrected to an effective quadratic theory. Numerical solutions for the anisotropic g…
Isotropisation of Quadratic Gravity: Scalar and Tensor Components
Daniel Müller, Márcio E. S. Alves, José C. N. de Araujo
It is believed that soon after the Planck era, spacetime should have a semi-classical nature. Therefore, it is unavoidable to modify the theory of General Relativity or look for al…
Numerical Bianchi I solutions in semi-classical gravitation
Sandro P. Vitenti, Daniel Müller
It is believed that soon after the Planck era, spacetime should have a semi-classical nature. In this context we consider quantum fields propagating in a classical gravitational fi…
Casimir Effect in Compact Universes
Daniel Muller
The Casimir effect in compact hyperbolic Universes was numerically obtained in previous publications. In this talk, I expose these results.
Casimir energy in multiply connected static hyperbolic Universes
D. Muller, H. V. Fagundes, R. Opher
We generalize a previously obtained result, for the case of a few other static hyperbolic universes with manifolds of nontrivial topology as spatial sections.
Casimir energy density in closed hyperbolic universes
Daniel Muller, Helio V. Fagundes
The original Casimir effect results from the difference in the vacuum energies of the electromagnetic field, between that in a region of space with boundary conditions and that in…
Casimir energy in a small volume multiply connected static hyperbolic pre-inflationary Universe
Daniel Muller, Helio V. Fagundes, Reuven Opher
A few years ago, Cornish, Spergel and Starkman (CSS), suggested that a multiply connected ``small'' Universe could allow for classical chaotic mixing as a pre-inflationary homogeni…