Large-Scale Response Theory for Gapless Lattice Fermi Systems in Low Dimensions

This thesis develops a rigorous large-scale response theory for gapless lattice Fermi systems in low dimensions, focusing on the mathematical validity of linear response -- the Kubo formula -- for transport in gapless systems, where the absence of a spectral gap prevents the direct use of standard adiabatic theorems. After reviewing fundamental results on many-body lattice fermions, we first analyse the transport properties of non-interacting, gapless, one-dimensional quantum systems and o...

A distance‐based framework for causal discovery from high‐dimensional time series

Unveiling causal relationships between time-dependent variables, observed as time series, is a challenge with countless applications across diverse scientific fields. This task lies at the heart of a research area known as causal discovery. In this thesis, we introduce a framework for causal discovery which is based on the quantification of the information content of different distance measures, built with suitable subsets of the observed variables. Focusing on distances, rather than di...

Sensory Neuron Rewiring in Pancreatic Ductal Adenocarcinoma: from Single-Cell RNA Profiling to Extracellular Vesicles-based strategies

Background & Aims: Neuronal innervation of the pancreas has historically been characterized using marker-based classification and physiological studies, but its transcriptomic landscape remains only partially explored. A detailed molecular profile of pancreatic sensory neurons could provide insights into their role in health and disease, particularly in pancreatic ductal adenocarcinoma (PDAC), where neural remodeling influences tumor progression and pain signaling. Methods: Wild-type an...

Winds of Change: The Decisive Role of Mass Loss in the Evolution of Very Massive Stars

Massive and very massive stars are among the most influential objects in our Universe, being key agents in chemical enrichment, sources of ionizing photons, and representing progenitors of extreme explosions and exotic compact objects. Despite significant progress in our understanding of stellar structure and evolution over the past century, there remain open questions regarding the physical processes of very massive stars (above ∼ 100 M⊙) formation and evolution. The evolution of the most ma...

QUBO-Based Sampling of Lattice Polymers with Classical and Quantum Computers

Charting the SHORES of the Radio Sky - Investigating extragalactic source populations through radio surveys

Surveys of galaxies are among the most powerful tools to investigate the Universe, allowing us to trace the statistical properties of large samples and to connect them to the physical processes driving galaxy evolution. Radio observations, in particular, have historically played a significant role — from settling the steady-state versus Big Bang debate through radio number counts, to shaping our understanding of Active Galactic Nuclei (AGN) and, more recently, uncovering obscured galaxy popul...

Lattice field theories for polymer systems

Modified Gravity In Galaxy Clusters: Insights From The Caustic Technique

On the Geometry of Ends of Ricci Shrinkers

In this thesis we study a particular type of Riemannian manifolds, namely gradient shrinking Ricci solitons, or Ricci shrinkers for short. Besides being generalisations of positive Einstein manifolds, Ricci shrinkers play a fundamental role in Ricci flow theory, modeling the finite-time singularities of the flow. While Ricci shrinkers are fully classified in dimensions two and three, in higher dimensions such a classification is far from being complete, and it is customary to study instead th...