Astrophysics and Space Science in Marche III: Big Bang, Big stars, Big Computers

Contribution List

26. A Forest of Primordial Black Holes: Type I and Type II Formation in Stochastic Inflation

Chiara Animali (UCLouvain)

Talk

Stochastic trees describe the inflationary structure of spacetime generated by stochastic inflation as a branching process.
In this talk, I will show that a sampled implementation of the compaction function can be constructed on such trees, enabling a refined treatment of the impact of quantum diffusion on primordial black hole (PBH) formation. Type I and type II populations of PBHs can also...

19. Addressing Systematics in Large Galaxy Surveys: a new approach to exploit data and simulations

Francesca Passalacqua (INFN Padova)

Talk

Modern large galaxy surveys have reached a level of statistical precision where observational systematics dominate the error budget of large-scale structure measurements. Accurately quantifying and mitigating these effects is therefore essential to avoid biased cosmological constraints and to fully exploit the potential of current and upcoming surveys.

Observational systematics are...

47. An Spline Persistence Model for Euclid NISP H2RG Detectors

Amirmohammad Chegeni (Università degli Studi di Padova & INFN Padova)

Talk

The Euclid mission is the European Space Agency's (ESA) cosmology mission designed to map approximately 1.5 billion galaxies over 14,000 deg² to investigate the nature of dark energy and dark matter through weak gravitational lensing and galaxy clustering, combining high‑resolution optical imaging (VIS) with near‑infrared imaging and spectroscopy (NISP).Image persistence in large-format HgCdTe...

33. Anisotropic expansion in the Laniakea region from supernovae luminosity-distance kinematics

Francesco Sorrenti (ICC - University of Barcelona)

Talk

Peculiar velocities have emerged as essential tools in modern cosmology and astrophysics, playing a key role in the study of current cosmic tensions, such as the dipole tension and the Hubble tension. A particularly compelling application lies in the use of Type Ia supernova (SNIa) luminosity distances to probe the underlying large-scale matter distribution. In this talk, I will show that the...

28. Are Oscillons in Non-Minimally Coupled Theories Frame-Covariant?

Andrea Iacobellis

Talk

Abstract
Non-minimally coupled scalar theories can be written in a Jordan frame, where the scalar field couples directly to curvature, or in an Einstein frame, where gravity is canonical but the scalar sector is transformed. We ask whether an oscillon identified in one frame remains an oscillon after transforming to the other frame and taking the nonrelativistic limit, given conformal and...

29. Charged accretion Tori around Schwarzschild black hole: self-generated electromagnetic fields and their effect on disc structure

Serena Gambino (Scuola Superiore Meridionale)

Talk

We present a model of a charged, barotropic, thick accretion disc around a Schwarzschild black hole. In this model, the electromagnetic field is entirely self-generated by the azimuthal current of the accreting fluid. The vector potential is modelled using a heuristic expression inspired by the leading-order multipolar expansion of a circular current loop. We obtain two-dimensional maps of the...

36. Cosmic-Ray Energy Dissipation Mechanisms in AGN Plasmas: Photopion, Collisional, and Synchrotron Losses

Efe Yenice

Talk

Cosmic rays are an important non-thermal component of active galac
tic nuclei (AGN) and may contribute significantly to the pressure balance
and energy transport within galactic nuclei. The efficiency of cosmic-ray
confinement and survival strongly depends on the surrounding plasma
conditions, radiation fields, particle densities, and magnetic environments.
In this study, we compare the...

13. Dark Hydrogenic Atoms and Ions as Baryonic Dark Matter and their Role in Structure Formation

Eugene Oks (Auburn University, USA)

Talk

The explanation of a puzzling observation by Bowman et al 2018 (Nature, 555, 67) of the redshifted 21 cm spectral line from the early Universe, where it was found that the absorption in this line was about 2 to 3 times stronger than predicted by the standard cosmology and thus the primordial hydrogen gas was significantly cooler than predicted by the standard cosmology, required as the cooling...

37. Dark Matter Dominance and Disk Stability in the Dwarf Irregular Galaxy NGC 3741

Efe Yenice

Talk

We present a detailed analysis of the dark matter distribution and disk
stability of the dwarf irregular galaxy NGC 3741 using multi-wavelength
observations. HI, optical, and near-ultraviolet (NUV) imaging data were
retrieved from the SkyView Virtual Observatory, providing a comprehen
sive view of both the gaseous and stellar components.
Using the HI surface density and rotation curve...

21. Echoes of Curvature: Cosmic Topology & Lens Spaces

Mikel Martin Barandiaran (Instituto de Física Teórica IFT UAM-CSIC)

Talk

The possibility of our Universe having a non-trivial spatial topology has received significant attention recently, as it could serve as a potential explanation of the Cosmic Microwave Background (CMB) large-angle anomalies and have interesting phenomenology in the early Universe. So far most efforts to study the shape of the cosmos have focused on spatially flat models, such as the simple...

34. Gravitational waves: Where data science meets physics

Enrico Barausse (SISSA (Trieste, Italy))

Talk

Gravitational waves from mergers of compact objects, first predicted
by Einstein and confirmed through direct observation in 2015, have
revolutionized astrophysics. With next-generation detectors coming
online in the next decade, we anticipate observing thousands of such
events, offering unprecedented insights into strong-field gravity,
black hole dynamics, and cosmic structure formation....

24. How the Big Collaboration is Trying to Find Optical Counterparts of GWs

Nino Kochiashvili (Abastumani Astrophysical Observatory, Georgia)

Talk

The GRANDMA network's efforts in searching for optical counterparts of gravitational waves will be presented.
GRANDMA is a growing collaboration that brings together telescopes and scientific institutions from many countries around the world. Our telescopes are located in different parts of the Earth, in both the Northern and Southern Hemispheres. We use wide-field and narrow-field...

31. Improving H0 constraints from joint Planck and XMM-Newton observations of galaxy clusters

Federico De Luca (Università degli studi di Roma "Tor Vergata")

Talk

Observations of galaxy clusters offer several ways to constrain cosmological models. In particular, the combination of X-ray and millimetre observations of their intracluster medium can be used to measure the Hubble constant, $H_0$, independently of both CMB-based estimates and local distance-ladder measurements. However, the application of this method is limited by several astrophysical and...

22. Inflationary magnetogenesis with massive vector fields and Schwinger effect

Mattia Dubbini (University of Camerino)

Talk

We investigate inflationary magnetogenesis considering massive electromagnetic fields, including scalar particle production via the Schwinger effect and the backreaction induced on the background electric energy density. As long as the Schwinger effect is neglected, we fully quantize the electromagnetic field and solve the equations of motion for transverse and longitudinal modes, computing...

16. Linear perturbation theory and structure formation in a Brans–Dicke theory of gravity without dark matter

Lorenzo Gervani (University of Turin)

Talk

We investigate the formation of the large-scale cosmic structure in a scalar-tensor theory of gravity belonging to the class of the Brans-Dicke theories. The universe contains baryonic matter alone and neither dark matter nor dark energy. The two arbitrary functions of the scalar field characterizing the kinetic term and the self-interaction potential are set to W (φ) = −1 and V (φ) = −Ξφ,...

30. Mapping the redshift drift at various redshifts through cosmography

Anna Chiara Alfano (Scuola Superiore Meridionale)

Talk

The redshift drift provides a kinematic test of the cosmic expansion history through the slow time variation of the redshift of comoving sources. Motivated by the expected Sandage-Loeb measurements from future facilities, the drift is investigated within a cosmographic framework, modeling the Hubble rate through both a second-order Taylor expansion and a (2,1) Padé approximant. The constraints...

43. Neutron--hidden neutron mixing as a component of dark matter

Mr Francesco Lottatori (University of Salerno)

Talk

We study the mixing between a neutron and a hidden neutron within the framework of quantum field theory in curved spacetime. We show that in static and spherically symmetric geometries, the expectation value of the energy-momentum tensor in the mixed vacuum can take the form of a pressureless fluid. In the weak-field limit, we derive an effective condensate density that modifies Poisson’s...

35. Newtonian and GR simulations on nonlinear scales: from frame-dragging to massive BH seeds

Dr Marco Bruni (Institute of Cosmology and Gravitation, University of Portsmouth)

Talk

In this talk I will give an overview of work on non-perturbative nonlinear structure formation in ΛCDM in the context of General Relativity (GR). Using a "post-Friedmann" approximation, I will show how, at leading order, the gravito-magnetic vector potential (AKA frame-dragging potential) is generated by the momentum density on nonlinear scales, and can be extracted from ILLUSTRIS ...

23. Next-generation CMB polarization data reduction: Scalable map-making and $1/f$ noise mitigation with BrahMap

Avinash Anand (University of Rome "Tor Vergata")

Talk

As CMB polarization experiments target the primordial B-mode signal, addressing complex foregrounds and systematics requires deploying an unprecedentedly large number of detectors in their focal planes. The resulting data volume will be enormous, posing a critical data reduction challenge. To address this, we present BrahMap: a modular, scalable, and HPC-ready map-making framework designed for...

39. Parameter estimation of generalized Ghosh black holes using shadow observables and Event Horizon Telescope Constraints

Himanshi Gulia (Netaji Subhas University of Technology)

Talk

The Event Horizon Telescope images of M87 and Sgr A give us a unique chance to test gravity in the strong field regime and assess deviations from the Kerr solution. We study the shadows of rotating nonsingular black holes—namely, generalized Ghosh black holes (GGBHs), given by the mass function $m(r) = M e^{-(k/r)^n}$, which reduces to the Kerr black hole ($k \to 0$) and to the original...

41. Preparing Cosmological Simulations for heterogeneous European clusters: CINECA's Contributions to OpenGadget within the SPACE-CoE

Alessandro Romeo (CINECA)

Talk

Simulating the formation of large-scale structure in the Universe - from cosmic filaments to galaxy clusters - requires solving gravity for hundreds of millions of particles across a vast range of spatial scales. As HPC systems increasingly rely on GPU accelerators, ensuring that cosmological codes can exploit this hardware efficiently has become a critical challenge.
Within the SPACE-CoE...

46. Probing scalar-field dark matter with single-arm interferometry

Antonio Capolupo (University of Salerno and INFN)

Talk

We investigate the interaction between photons and a scalar dark matter field, and propose a single-arm interferometric scheme to detect its effects and constrain the parameter space of scalar dark matter models. By considering a coherent light beam combined with two spatially separated squeezing operations, we show that the photon–scalar dark matter interaction induces a measurable deviation...

18. Quasinormal Modes as Spectral Probes of Spacetime Geometry: From Plebański-Demiański to Black Hole Mimickers

Gabriele Bianchini (University of Camerino)

Talk

We study gravitational quasinormal modes (QNMs) for two classes of compact object geometries, using the spectrum as a direct probe of spacetime structure and physical parameters. We focus on gravitational QNMs as they encode the intrinsic spectrum of the metric and characterize its stability independently of any interaction with external fields.
In the first part, we consider the...

17. Redshift-dependent cosmic birefringence from pseudoscalar fields

Matteo Galaverni (Vatican Observatory - INAF/OAS - INFN Bologna)

Talk

Recent analyses of Cosmic Microwave Background (CMB) polarization data from satellite missions (both WMAP and Planck) as well as from the Atacama Cosmology Telescope, suggest a possible hint of cosmic birefringence (rotation of the linear polarization plane). We discuss the imprints of a redshift/time dependent cosmological pseudoscalar field on the CMB polarization power spectra. We consider...

40. Reframing information geometry via symmetric teleparallel gravity

Tatsuaki WADA (Ibaraki University)

Talk

Information geometry (IG) has traditionally been formulated within the framework of Riemannian geometry and dual affine connections. In this work, we reframe this foundational structure by introducing the geometric machinery of symmetric teleparallel gravity (STG). By requiring both curvature and torsion to vanish globally on the statistical manifold, the fundamental properties of the...

42. Scalable early warning for BNS mergers in next-generation ground-based detectors using SBI

Martin Gerini (UCLouvain)

Talk

Third-Generation (3G) observatories will observe Binary Neutron Star coalescences for hours before merger. Over these extended windows, Earth's motion induces signal modulations that render standard approaches computationally prohibitive for low-latency searches. To overcome this, we propose a 2D Convolutional Neural Network (CNN) processing multi-detector, complex Short Fourier Transform...

27. Scalar perturbations from a two-field unified warm-inflationary cosmological model

Tommaso Mengoni (University of Camerino)

Talk

Warm inflation offers an alternative description of the early Universe in which dissipative effects and radiation production are already present during the accelerated expansion. In this talk, I will discuss the scalar perturbation sector of warm-inflationary models, focusing on its extension from the standard single-field framework to two-scalar-field scenarios.

Starting from known...

14. Scalar–Vector–Tensor Gravity in FLRW Cosmology: Universal Structure versus Model Dependence

Yaghoub Heydarzade (Department of Mathematics, Bilkent University, Turkey)

Talk

We generalize our previous theorem for FLRW spacetimes within the framework of generic metric gravity theories. In earlier work, we proved that, in the absence of matter fields, the field equations of any metric gravity theory constructed from the curvature tensor and its covariant derivatives reduce in FLRW spacetime to the Einstein equations with an effective perfect-fluid source. In the...

45. Searching for Dark Sector with Neutron Interferometer

Prof. Antonio Capolupo (Università degli studi di Salerno), Gabriele Pisacane (Università degli studi di Salerno)

Talk

Hidden-sector extensions of the Standard Model predict a neutral partner of the neutron ($n'$), leading to oscillations between visible and dark baryonic states. We propose a Mach–Zehnder interferometer with very cold neutrons to detect this phenomenon. By combining controlled phase shifts, tunable magnetic fields, and material potentials, the setup maps $n \to n'$ oscillations into intensity...

32. Some Problems Between the Classical Big Bang Theory and Observational Data

Nino Kochiashvili (Abastumani Astrophysical Observatory, Georgia)

Talk

At least two of the key claims of the classical Big Bang theory, which concerned the very point of origin of the Universe, remain strangely unscientific even today: a) the universe arose from "nothing" and b) it then expanded inflationary.
I will briefly examine some discrepancies between theory and observations and propose a different starting point, attempting to build a model of the...

48. Stealth fields in cosmology: primordial magnetogenesis and the Theta-shift redefinition method

Antonino Marino

Talk

Experimental evidence shows that the Universe is currently permeated by large-scale magnetic fields whose strength is expected to reach the nano-Gauss level. The origin of these magnetic fields remains a matter of active investigation.
Although no consensus has yet been reached on the exact paradigm that explains these observations, the literature has increasingly favored primordial...

20. The challenges of using Baryon Acoustic Oscillations distances for cosmology

Stefano Anselmi (INFN, Sezione di Padova)

Talk

One of the landmarks guiding our understanding of physical cosmology is the large-scale structure, defined as the large scale distributions of galaxies, as observed by galaxy surveys. In this context, the so-called Baryon Acoustic Oscillations, are considered one of the most powerful cosmological probes. They are generally deemed to provide distance measures independent of a specific...

38. The power of Normalizing Flows for Bayesian inference

Eleonora Villa (INAF - IASF MI)

Talk

Pulsar Timing Array data analysis faces severe computational challenges as parameter spaces scale with the number of pulsars. I present two Normalizing Flows (NFs) based strategies to accelerate and improve Bayesian inference for stochastic gravitational wave background (SGWB). First, integrating NFs into the importance nested sampling framework i-nessai yields speedups of one to three orders...

25. Three-dimensional signatures of Cosmic Topology

Deyan Mihaylov (Case Western Reserve University / Sofia University)

Talk

Cosmic topology remains one of the last frontiers of modern cosmology. Recent theoretical developments, together with the rapidly growing volume and precision of cosmological data, now make it possible to probe the global shape of the Universe with renewed sensitivity. While current and future cosmic microwave background observations continue to provide powerful tests of topology, I will show...

44. Wave-Dark-Matter Halo Formation and Relaxation on a Neutrino Condensate

Simone Monda (Università degli Studi di Salerno)

Talk

We investigate the formation and relaxation of dark matter halos in the framework of wave dark matter particles evolving on a neutrino-condensate background. We numerically solve the Schrödinger–Poisson system to model the dynamical evolution of ultralight bosonic dark matter in the presence of a neutrino condensate. The latter is included as an additional source term in the Poisson equation,...