Related papers: Structure formation simulations with momentum exch…
Low energy interactions between particles are often characterised by elastic scattering. Just as electrons undergo Thomson scattering with photons, dark matter particles may experience an analogous form of momentum exchange with dark…
No experimental test precludes the possibility that the dark matter experiences forces beyond general relativity -- in fact, a variety of cosmic microwave background observations suggest greater late-time structure than predicted in the…
We describe cosmological simulation techniques and their application to studies of cosmic structure formation, with particular attention to recent hydrodynamic simulations of structure in the high redshift universe. Collisionless N-body…
Initial conditions in cosmological $N$-body simulations are typically generated by displacing particles from a regular cubic lattice using a correlated field derived from the linear power spectrum, often via the Zel'dovich approximation.…
The dark energy dominated warm dark matter (WDM) model is a promising alternative cosmological scenario. We explore large-scale structure formation in this paradigm. We do this in two different ways: with the halo model approach and with…
(Abridged) An interaction between Cold Dark Matter (CDM) and a classical scalar field playing the role of the cosmic dark energy (DE) might provide long-range dark interactions without conflicting with solar system bounds. Although…
In a recent article, Kleidis and Spyrou (2015) proposed that both dark matter (DM) and dark energy (DE) can be treated as a single component, if accommodated in the context of a polytropic DM fluid with thermodynamical content. Depending…
The CMB is a remarkably distortionless blackbody, and this strongly constrains the amount of energy that can have been injected at high redshift, thereby limiting the role that hydrodynamical amplification can have played in cosmic…
We examine the cosmological redshift-space distortion effect on the power spectrum of the objects at high-redshifts, which is an unavoidable observational contamination in general relativistic cosmology. In particular, we consider the…
We study a coupled quintessence model with pure momentum exchange and present the effects of such an interaction on the Cosmic Microwave Background (CMB) and matter power spectrum. For a wide range of negative values of the coupling…
The currently standard theory of cosmic structure formation posits that the present-day clumpy appearance of the universe developed through gravitational amplification of the matter density fluctuations that are generated in the very early…
We study the nonlinear growth of cosmic structure in different dark energy models, using large volume N-body simulations. We consider a range of quintessence models which feature both rapidly and slowly varying dark energy equations of…
We discuss the thermodynamic and dynamical properties of a variable dark energy model with density scaling as $\rho_x \propto (1+z)^{m}$, z being the redshift. These models lead to the creation/disruption of matter and radiation, which…
Non-linear evolution of cosmological energy density fluctuations triggers deviations from Gaussianity in the temperature distribution of the cosmic microwave background. A method to estimate these deviations is proposed. N-body simulations…
Tensions between cosmological parameters (in particular the local expansion rate $H_0$ and the amplitude of matter clustering $S_8$) inferred from low-redshift data and data from the cosmic microwave background (CMB) and large-scale…
The standard cold dark matter (CDM) model predicts too many and too dense small structures. We consider an alternative model that the dark matter undergoes two-body decays with cosmological lifetime $\tau$ into only one type of massive…
In cosmology numerical simulations of structure formation are now of central importance, as they are the sole instrument for providing detailed predictions of current cosmological models for a whole class of important constraining…
We compare a large suite of theoretical cosmological models to observational data from the cosmic microwave background, baryon acoustic oscillation measurements of expansion, Type Ia SNe measurements of expansion, redshift space distortion…
This study explores the impact of cosmic curvature on structure formation through general relativistic first-order perturbation theory. We analyze continuity and Euler equations, incorporating cosmic curvature into Einstein equations.…
Future large-scale structure surveys of the Universe will aim to constrain the cosmological model and the true nature of dark energy with unprecedented accuracy. In order for these surveys to achieve their designed goals, they will require…