In this talk I will discuss PRyMordial: a program dedicated to the computation of observables in the early universe with a focus on the cosmological era of Big Bang Nucleosynthesis (BBN). The code is the first of its kind written in python and offers fast and precise evaluation of both the BBN light-element abundances and the effective number of relativistic degrees of freedom. PRyMordial was...
The Navier-Stokes equations are ubiquitous in the physical description of our universe, but their relativistic counterpart, as originally formulated many decades ago, suffer severe issues. Alternative formulations, like the widely used Muller-Israel-Stewart (MIS) theories that successfully describe the quark-gluon plasma, have also been recently found to present limitations. Moreover, weak...
The ICCUB Technology Unit is contributing to the software development and data processing of several projects of the Institute. The most important one is Gaia, where we develop data processing pipelines and catalogue validation tools, and research on data mining solutions including cloud computing. Gaia has even led to spin-off projects, related to light pollution or even cybersecurity, and we...
Holography (or the gauge/gravity correspondence) refers to the dual description of the same phenomena through two seemingly different theories: quantum field theory in four dimensions ("our world") and gravity in five dimensions. In some regimes, holography gives us a map to solve within one of the descriptions (classical Einstein gravity in 5D Anti-de-Sitter spacetime) something that is very...
The Milky Way is a dynamic system, exhibiting a wealth of complex processes revealed through the unprecedented precision of ESA's Gaia mission. Gaia's stellar data provide a detailed window into the ongoing dynamical evolution of our Galaxy. For instance, the Galactic bar appears to be slowing down in its angular rotation, while the outer disc shows perturbations likely caused by the passage...
Unstable domain wall (DW) networks in the early universe are cosmologically viable and can emit a large amount of gravitational waves (GW), both before and during annihilation. In my talk I will present recent results on the form of the generated GW spectrum, based on lattice simulations of the field dynamics in 3+1-dimensions.
The stars in the local stellar disc of the Milky Way (MW) exhibit a bimodal distribution in the chemistry of their alpha-process elements. This creates two distinct sequences: the high and low-alpha discs. Numerous hypotheses have been proposed to explain the origin of this bimodality, including the ‘two-infall’ model, which suggests two distinct epochs of gas accretion. This model is...
The merger of binary systems has been identified as the cause of peculiar class of astrophysical transients discovered within the last three decades. Archival pre-outburst data on the progenitors of these transients showed an interesting fact: all but one were Hertzsprung gap stars undergoing a phase of fast expansion after hydrogen exhaustion in the core of the more massive component. This...
Hadron spectroscopy plays an important role in understanding the strong interactions, from conventional hadrons to exotic states like hybrids with explicit gluonic components. Finite-Energy Sum Rules (FESR) link low-energy resonance dynamics with high-energy Regge behavior, providing a powerful theoretical framework to study these states. Building upon the JPAC's work on $\pi p \to \pi...
The Hubble parameter, H0, is one of the key parameters of the current cosmological model. But its value measured from the Cosmic Microwave Background in the early (distant) universe, differs from the value measured directly in the late (local) universe. Obviously, as all measurements are done in the same universe, they should be the same: any difference, a.k.a. tension between the early and...
The standard model of cosmology, known as ΛCDM, successfully explains a wide variety of observations spanning different epochs of cosmic evolution. However, its most abundant components—dark energy and dark matter—still lack a fundamental theoretical explanation. In addition, the past decade has highlighted several tensions between the model and observational data, potentially pointing to new...
The nuclear many-body problem poses a significant computational challenge. The Neural-Network Quantum States (NQS) method, leveraging machine learning, has emerged as a promising approach for nuclear structure and quantum many-body simulations [1-4]. This variational method employs neural networks as flexible wave function ansätze, enabling the representation of complex quantum states.
In...
RR Lyrae stars are a class of variable stars whose luminosity varies periodically, with periods ranging from 0.2 to 1 day. The shape and properties of their light curves correlate with intrinsic characteristics such as luminosity and metallicity (in astrophysics, "metals" refer to all elements heavier than helium). For this reason, RR Lyrae stars are considered standard candles and have been...
The intricate nature of nucleon-nucleon interactions within the atomic nucleus gives rise to a rich array of collective phenomena, including the emergence of permanently deformed shapes in the nucleus' intrinsic frame of reference$^{[1]}$. While spherical shapes are favored near magic numbers, most nuclei exhibit some degree of deformation, and many display shape coexistence within a narrow...
The study of excitation spectra of hadrons is a crucial experimental tool to understand the binding mechanism of quarks in the strong interaction. While big advances have been made in recent years in the study of heavy-flavour hadrons containing a charm (c) or beauty (b) quark, the field of multi-strange (s) baryons, especially $\Xi^{0,−}$ (ssu, ssd) and $\Omega^−$ (sss), is largely...
Gaia has provided the largest star map in history, but it has only detected the brightest 2% of our Galaxy's stars. Failing to account for this limitation can lead to inaccurate conclusions about the processes that have shaped our Galaxy. In this talk, I will discuss statistical methods to estimate Gaia's completeness and how these can influence the scientific conclusions about the Milky Way.
I will introduce a couple of recent exciting results and open questions in particle physics from cosmology and astrophysics.
