Cosmic Parallax as a probe of late time anisotropic expansion (2009)
Quercellini, Claudia, Cabella, Paolo, Amendola, Luca, Quartin, Miguel, Balbi, Amedeo
Cosmic parallax is the change of angular separation between pair of sources at cosmological distances induced by an anisotropic expansion. An accurate astrometric experiment like Gaia could observe...
Optimising Boltzmann codes for the Planck era (2009)
Hamann, Jan, Balbi, Amedeo, Lesgourgues, Julien, Quercellini, Claudia
High precision measurements of the Cosmic Microwave Background (CMB) anisotropies, as can be expected from the Planck satellite, will require high-accuracy theoretical predictions as well. One...
The equations of medieval cosmology (2008)
Buonanno, Roberto, Quercellini, Claudia
In Dantean cosmography the Universe is described as a series of concentric spheres with all the known planets embedded in their rotation motion, the Earth located at the centre and Lucifer at the...
Quercellini, Claudia, Quartin, Miguel, Amendola, Luca
Refined astrometry measurements allow us to detect large-scale deviations from isotropy through real-time observations of changes in the angular separation between sources at cosmic distances. This...
Affine parameterization of the dark sector: costraints from WMAP5 and SDSS (2008)
Pietrobon, Davide, Balbi, Amedeo, Bruni, Marco, Quercellini, Claudia
We study a set of universe models where the dark sector is described by a perfect fluid with an affine equation of state $P=P_0+\alpha \rho$, focusing specifically on cosmological perturbations in a...
Mapping the galactic gravitational potential with peculiar acceleration (2008)
Quercellini, Claudia, Amendola, Luca, Balbi, Amedeo
It has been suggested recently that the change in cosmological redshift (the Sandage test of expansion) could be observed in the next generation of large telescopes and ultra-stable spectrographs. In...
Late universe dynamics with scale-independent linear couplings in the dark sector (2008)
Quercellini, Claudia, Bruni, Marco, Balbi, Amedeo, Pietrobon, Davide
We explore the dynamics of cosmological models with two coupled dark components with energy densities $\rho_A$ and $\rho_B$. We assume that the coupling is of the form $Q=Hq(\rho_A,\rho_B)$, so that...
Amendola, Luca, Quercellini, Claudia, Balbi, Amedeo
It has been proposed recently to observe the change in cosmological redshift of distant galaxies or quasars with the next generation of large telescope and ultra-stable spectrographs (the so-called...
Affine equation of state from quintessence and k-essence fields (2007)
Quercellini, Claudia, Bruni, Marco, Balbi, Amedeo
We explore the possibility that a scalar field with appropriate Lagrangian can mimic a perfect fluid with an affine barotropic equation of state. The latter can be thought of as a generic...
Balbi, Amedeo, Bruni, Marco, Quercellini, Claudia
We consider the hypothesis that dark energy and dark matter are the two faces of a single dark component, a unified dark matter (UDM) that we assume can be modeled by the affine equation of state...
Constraints on perfect fluid and scalar field dark energy models from future redshift surveys (2004)
Amendola, Luca, Quercellini, Claudia, Giallongo, Emanuele
We discuss the constraints that future photometric and spectroscopic redshift surveys can put on dark energy through the baryon oscillations of the power spectrum. We model the dark energy either...
Skewness as a test of the equivalence principle (2004)
Amendola, Luca, Quercellini, Claudia
The skewness of the large scale distribution of matter has long been known to be a probe of gravitational clustering. Here we show that the skewness is also a probe of violation of the equivalence...
N-body simulations for coupled dark energy: halo mass function and density profiles (2003)
Maccio', Andrea V., Quercellini, Claudia, Mainini, Roberto, Amendola, Luca, Bonometto, Silvio A.
We present the results of a series of N-body simulations in cosmologies where dark matter (DM) is coupled to dark energy (DE), so easing the cosmic coincidence problem. The dark-dark coupling...
Tracking and coupled dark energy as seen by WMAP (2003)
Amendola, Luca, Quercellini, Claudia
The satellite experiment WMAP has produced for the first time a high-coverage, high resolution survey of the microwave sky, releasing publicly available data that are likely to remain unrivalled for...
The nature of dark energy (2002)
Amendola,Luca, Quercellini,Claudia, Tocchini-Valentini,Domenico, Pasqui,Alessandro
According to a variety of cosmological observations at small and large redshifts, the universe is composed by a large fraction of a weakly clustered component with negative pressure, called dark...
Amendola, Luca, Quercellini, Claudia, Tocchini-Valentini, Domenico, Pasqui, Alessandro
It is well-known that even high quality cosmic microwave background (CMB) observations are not sufficient on their own to determine the equation of state of the dark energy, due to the effect of the...