arXiv subjects

Antonio Rizzo

Publications and source records attributed to Antonio Rizzo.

4 recordsLinked to original sources

arXiv2026

Symbiosis as a systemic catalyst and the impossibility of coalitions in optimal networks

The stability of complex systems hinges on the tension between individual incentives and collective welfare. Modeling these dynamics through strategic network interactions based on anti-coordination, we formally prove that any globally optimal configuration constitutes a Strong Nash Equilibrium, creating topological barriers against collective deviations. However, in sub-optimal states, strictly individualistic agents remain trapped in stagnant equilibria. We show that coalition formation acts as a vital catalyst for global efficiency. Paralleling Tomasello's evolutionary theory of shared intentionality, the emergence of symbiotic joint agency overcomes selfish stagnation and drives the system toward optimal niche partitioning. We validate our framework through extensive computational simulations and apply it to an empirical pollination network, demonstrating how symbiosis may steer real-world ecosystems toward maximum resilience. We uncover metastable dynamics where coalitions continuously reconfigure, revealing that biological evolution relies on a perpetual, adaptive balance between competition and cooperation.

physics.soc-ph↗

arXiv2025

Toward Explainable Offline RL: Analyzing Representations in Intrinsically Motivated Decision Transformers

Elastic Decision Transformers (EDTs) have proved to be particularly successful in offline reinforcement learning, offering a flexible framework that unifies sequence modeling with decision-making under uncertainty. Recent research has shown that incorporating intrinsic motivation mechanisms into EDTs improves performance across exploration tasks, yet the representational mechanisms underlying these improvements remain unexplored. In this paper, we introduce a systematic post-hoc explainability framework to analyze how intrinsic motivation shapes learned embeddings in EDTs. Through statistical analysis of embedding properties (including covariance structure, vector magnitudes, and orthogonality), we reveal that different intrinsic motivation variants create fundamentally different representational structures. Our analysis demonstrates environment-specific correlation patterns between embedding metrics and performance that explain why intrinsic motivation improves policy learning. These findings show that intrinsic motivation operates beyond simple exploration bonuses, acting as a representational prior that shapes embedding geometry in biologically plausible ways, creating environment-specific organizational structures that facilitate better decision-making.

cs.LG↗

arXiv2020

End-to-End Models for the Analysis of System 1 and System 2 Interactions based on Eye-Tracking Data

While theories postulating a dual cognitive system take hold, quantitative confirmations are still needed to understand and identify interactions between the two systems or conflict events. Eye movements are among the most direct markers of the individual attentive load and may serve as an important proxy of information. In this work we propose a computational method, within a modified visual version of the well-known Stroop test, for the identification of different tasks and potential conflicts events between the two systems through the collection and processing of data related to eye movements. A statistical analysis shows that the selected variables can characterize the variation of attentive load within different scenarios. Moreover, we show that Machine Learning techniques allow to distinguish between different tasks with a good classification accuracy and to investigate more in depth the gaze dynamics.

q-bio.NC↗

arXiv2015

Circular and linear magnetic birefringences in xenon at $λ= 1064$ nm

The circular and linear magnetic birefringences corresponding to the Faraday and the Cotton-Mouton effects, respectively, have been measured in xenon at $λ= 1064$ nm. The experimental setup is based on time dependent magnetic fields and a high finesse Fabry-Perot cavity. Our value of the Faraday effect is the first measurement at this wavelength. It is compared to theoretical predictions. Our uncertainty of a few percent yields an agreement at better than 1$σ$ with the computational estimate when relativistic effects are taken into account. Concerning the Cotton-Mouton effect, our measurement, the second ever published at $λ= 1064$ nm, agrees at better than $1σ$ with theoretical predictions. We also compare our error budget with those established for other experimental published values.

physics.optics↗