Galaxy clusters represent the top of hierarchical structure formation with the largest dark matter halos. Their abundance with respect to mass and redshift can be used to constrain cosmological parameters. The most extensive ...

Comprising the most massive gravitationally bound and relaxed structures in the Universe, galaxy clusters are essential in providing a deeper understanding of the properties of dark matter. Being cosmologically young ...

Evolution in the mass function of galaxy clusters sensitively traces both the expansion history of the Universe and cosmological structure formation. Hence, measuring the number density of galaxy clusters as a function of ...

Cosmology has recently entered an era of increasingly rich observational data sets, all being in agreement with a cosmological standard model that features only a small number of free parameters. One of the most powerful ...

Correlation functions are an omnipresent tool in astrophysics, and they are routinely used to study phenomena as diverse as the large-scale structure of the Universe, time-dependent pulsar signals, and the cosmic microwave ...

Systematic surveys of the extra-galactic sky have revealed the existence of large-scale structures in the Universe: the galaxy distribution is organized in a complex network of filaments surrounding underdense regions and ...

The formation of structures in the universe, such as galaxy clusters, depends sensitively on cosmological parameters. Measuring the abundance of clusters as a function of mass and redshift therefore yields a way to constrain ...

The Milky Way (MW) Galaxy is a unique laboratory to study the evolution of spiral galaxies, offering great sensitivities and angular resolutions with respect to observations of other galaxies. There, the large distance and ...

One of the most commonly asked questions in astrophysics today refers to the nature of dark energy. The characteristics of this parameter are imprinted in the large-scale structure of matter and accordingly also in the ......

This work is concerned with different aspects of observational cosmology. It covers a broad range of problems that one needs to deal with in optical astronomy.
Three introduction chapters about cosmology, gravitational ...