Related papers: Cosmic strings, domain walls and environment-depen…
We study structure formation in alternative cosmological models constrained by background observations, including $\Lambda$CDM, wCDM, the Chevallier-Polarski-Linder parametrisation and a flexible Chebyshev expansion of the dark energy…
In the symmetron mechanism, the fifth force mediated by a coupled scalar field (the symmetron) is suppressed in high-density regions due to the restoration of symmetry in the symmetron potential. In this paper we study the background…
A quintessence scalar field or cosmon interacting with neutrinos can have important effects on cosmological structure formation. Within growing neutrino models the coupling becomes effective only in recent times, when neutrinos become…
Cosmological consequences of a string-motivated dark energy scenario featuring a scalar field coupled to the Gauss-Bonnet invariant are investigated. We study the evolution of the universe in such a model, identifying its key properties.…
A growing neutrino mass can stop the dynamical evolution of a dark energy scalar field, thus explaining the 'why now' problem. We show that such models lead to a substantial neutrino clustering on the scales of superclusters. Nonlinear…
The evidence in favor of a dark energy component dominating the Universe, and driving its presently accelerated expansion, has progressively grown during the last decade of cosmological observations. If this dark energy is given by a…
The symmetron is a dark energy and dark matter candidate that forms topological defects in the late-time universe and holds the promise of resolving some of the cosmological tensions. We performed high-resolution simulations of the…
Motivated in part by string theory, we consider the idea that the standard LambdaCDM cosmological model might be modified by the effect of a long-range scalar dark matter interaction. The variant of this widely-discussed notion considered…
We explore the effects of massive neutrinos on the cosmic web using the FLAMINGO simulations. We classify the cosmic web into voids, sheets, filaments, and clusters, and find that massive neutrinos affect the environment by decreasing the…
We lay out the framework to numerically study nonlinear structure formation in the context of scalar-field-coupled cold dark matter models (phiCDM models) where the scalar field phi serves as dynamical dark energy. Adopting parameters for…
The recently proposed Multi-coupled Dark Energy (McDE) scenario - characterised by two distinct Cold Dark Matter (CDM) particle species with opposite couplings to a Dark Energy scalar field - introduces a number of novel features in the…
We highlight a viable mechanism leading to the formation of dark energy structures on sub-horizon cosmological scales, starting from linear perturbations in scalar-tensor cosmologies. We show that the coupling of the dark energy scalar…
The recent observational evidence for the current cosmic acceleration have stimulated renewed interest in alternative cosmologies, such as scenarios with interaction in the dark sector (dark matter and dark energy). In general, such models…
We consider the evolution of linear perturbations in models with a nonminimal coupling between dark matter and scalar field dark energy. Growth of matter inhomogeneities in two examples of such models proposed in the literature are…
We investigate how the use of higher wavenumbers (smaller scales) in the galaxy clustering power spectrum influences cosmological constraints. We take into account uncertainties from nonlinear density fluctuations, (scale dependent) galaxy…
We investigate generalized interacting dark matter-dark energy scenarios with a time-dependent coupling parameter, allowing also for freedom in the neutrino sector. The models are tested in the phantom and quintessence regimes,…
Massive neutrinos suppress the growth of cosmic structure on small, non-linear, scales. It is thus often proposed that using statistics beyond the power spectrum can tighten constraints on the neutrino mass by extracting additional…
We use large N-body simulations of dissipationless gravitational clustering in cold dark matter (CDM) cosmologies to study whether the properties of dark matter halos are affected by their environment. We look for correlations between the…
Hamilton et al. have suggested an invaluable scaling formula which describes how the power spectra of density fluctuations evolve into the nonlinear regime of hierarchical clustering. This paper presents an extension of their method to…
In recent work, it was shown that velocity-dependent forces between moving strings or branes lead to an accelerating expanding universe without assuming the existence of a cosmological constant. Here we show that the repulsive…