In this article, I introduce ideas and techniques to extract information about the equation of
state of matter at very high densities from gravitational waves emitted before, during and …

Axion-like particle (ALP) dark matter shows distinctive behavior on scales where wavelike
effects dominate over self-gravity. Ultralight axions are candidates for fuzzy dark matter …

I present an introduction and topical review on axions as a dark matter candidate. Emphasis
is placed on issues surrounding the cosmology of axion dark matter that are relevant for …

We study Bose-Einstein condensation and the formation of Bose stars in virialized dark
matter halos and miniclusters by universal gravitational interactions. We prove that this …

We study the small scale structure of axion dark matter in the post-inflationary scenario,
which predicts the formation of low-mass, high density clumps of gravitationally bound …

Binary systems containing boson stars—self-gravitating configurations of a complex scalar
field—can potentially mimic black holes or neutron stars as gravitational-wave sources. We …

We apply current analytical knowledge on the characteristic mass and linear evolution of
miniclusters down to redshift z= 0 to the hypothetical minicluster distribution of the Milky …

A portion of light scalar dark matter, especially axions, may organize into gravitationally
bound clumps (stars) and be present in large number in the galaxy today. It is therefore of …

We study the nature of phase transitions between dilute and dense axion stars interpreted
as self-gravitating Bose-Einstein condensates. We develop a Newtonian model based on …

The particle that makes up the dark matter of the Universe could be an axion or axionlike
particle. A collection of axions can condense into a bound Bose-Einstein condensate called …