184 citations · 325 across the 8 of their papers we have counts for
8 papers
Unphysical properties in a class of interacting dark energy models
R. von Marttens, H. A. Borges, S. Carneiro +2
Models with non-gravitational interactions between the dark matter and dark energy components are an alternative to the standard cosmological scenario. These models are characteriz…
Matter growth in extended CDM cosmology
W. Zimdahl, H. E. S. Velten, W. C. Algoner
On the basis of a previously established scalar-tensor extension of the CDM model we develop an effective fluid approach for the matter growth function. This extended CDM (he…
Matter Perturbations in Scaling Cosmology
A. Romero Fuño, W. S. Hipólito-Ricaldi, W. Zimdahl
A suitable nonlinear interaction between dark matter with an energy density and dark energy with an energy density is known to give rise to a non-canonical scaling…
Viscous dark matter growth in (neo-)Newtonian cosmology
H. Velten, D. J. Schwarz, J. C. Fabris +1
We assume cold dark matter to possess a small bulk-viscous pressure which typically attenuates the growth of inhomogeneities. Explicit calculations, based on Eckart's theory of dis…
Viscous dark fluid Universe: a unified model of the dark sector?
W. Zimdahl, H. E. S. Velten, W. S. Hipólito-Ricaldi
The Universe is modeled as consisting of pressureless baryonic matter and a bulk viscous fluid which is supposed to represent a unified description of the dark sector. In the homog…
Bulk Viscous Cosmology
R. Colistete, J. C. Fabris, J. Tossa +1
We propose a scenario in which the dark components of the Universe are manifestations of a single bulk viscous fluid. Using dynamical system methods, a qualitative study of the hom…
Gas models for inflation and quintessence
W. Zimdahl, A. B. Balakin, D. J. Schwarz +1
Specific internal self-interactions in gaseous cosmic fluids are shown to give rise to effective negative pressures which may violate the strong energy condition. On this basis we…
Reheating and causal thermodynamics
Winfried Zimdahl, Diego Pavón, Roy Maartens
The reheating process in inflationary universe models is considered as an out-of-equilibrium mixture of two interacting and reacting fluids, and studied within the framework of cau…