I will review models in which dark matter is described by an ultralight field. In particular, I will focus on the cosmological perturbations of spin-0 and spin-1 candidates. I will highlight the main differences in their predictions, and discuss the possibility for distinguishing the spin of dark matter using data from the matter power spectrum.
Ultralight dark matter (ULDM) has emerged as a compelling candidate to explain the dark sector, motivated not only by its potential to resolve small-scale structure issues but also by its natural appearance in high-energy theories such as string compactifications, as well as the coincidence of the observed abundance in the case of spin-0 scalar dark matter. In this talk, I will discuss the...
The possibility of additional spin-2 particles beyond the graviton has attracted growing interest in both cosmology and high-energy theory. In particular, massive spin-2 fields, or “dark gravitons”, have emerged as compelling dark matter candidates. Such states naturally arise in consistent ghost-free extensions of General Relativity, such as bigravity. The dynamics of these fields are...
I will give a pedagogical review on traces of ultralight dark matter in the cosmological perturbations. Specifically, I will discuss the suppression of small-scale structures due to their quantum pressure and the effects of isocurvature perturbations.
Scalar field dark matter (SFDM) is an alternative candidate to standard
dark matter models, gaining attention due to the unique effects
associated with its ultra-light mass. While its dynamics have been
extensively studied across different scales, its full phenomenology
remains under active investigation. In particular, the role of
self-interactions and their impact on structure formation...
I will describe how post inflationary production mechanisms (and even some inflationary ones) of ultralight dark fields, naturally lead to a free-streaming/Jeans suppression as well as a Poisson fluctuation related enhancement in the matter power spectrum. The lack of observation of these features can provide relatively model independent bound on the mass of dark matter particles. In general...
Ultralight Dark Matter (ULDM) has emerged as a compelling alternative to the Cold Dark Matter paradigm at small scales, naturally producing solitonic cores at the center of halos and granular structures arising from wave interference. These features lead to distinctive dynamical effects, including the random motion of the core and dynamical heating of stars in galactic systems. In this work we...
In this talk, I will show how orbital resonances offer a new handle in the searches of GWs and ULDM. I will mainly focus on satellite and lunar laser ranging and binary pulsars.
Ultralight bosonic fields are well-motivated candidates for explaining dark matter, dark energy, and other open problems in cosmology. While scalars are the standard approach, higher-spin fields—including vectors and spin-2 gravitons—can exhibit similar behavior with distinctive phenomenology. This talk explores the cosmological evolution of such fields, emphasizing the isotropy theorem that...
I will discuss the ways in which non-linear behaviour of scalar field theories, in particular variations of the mass of the scalar with the density of the local environment, can both hinder and help the detection of such scalars. To illustrate this I will discuss chameleon dark energy scalars, and quadratically coupled ultra-light dark matter.
The nature of dark matter remains unknown to date, although several candidate particles are being considered in a dynamically changing research landscape. Scalar field dark matter is a prominent option that is being explored with precision instruments, such as atomic clocks and optical cavities.
In particular, low-mass (sub-eV) scalar field dark matter may induce apparent oscillations of...
In this talk I will explain how levitated sensors can be used to search for ultralight dark matter with different spins: scalar, vector, and tensor. I will focus on a magnetically levitated superconducting particle (maglev) and describe the experimental setup that creates the magnetic trap. I will then show how interactions with ultralight dark matter give rise to a force, leading to a...
Dark matter remains one of the most intriguing mysteries in our understanding of the universe. Recent theoretical advancements have motivated new experimental strategies to detect ultralight dark matter particles. This talk explores innovative methods for searching for these elusive particles using gravitational wave detectors. I will discuss how ultralight dark matter may generate detectable...
