Month: November 2024

06/12/2024 Pierre Roux @UniMi

Ngọc Nhi NguyễnSeminar UniMi 
Wednesday, December 6, 2024 - 14:00

Aula Dottorato,
Dipartimento di Matematica,
Università degli Studi di Milano,
Via Cesare Saldini 50.

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SPEAKER: Pierre Roux (Institut Camille Jordan, École Centrale de Lyon)

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Disentangling pulse-coupled oscillators in the mean-field regime through the pseudo-inverse in a dilated timescale

Systems of pulse-coupled oscillators model synchronization through singular interactions occurring at discrete times, when particles reach a specific firing phase. They have numerous applications in physics, biology and engineering, for example to cardiac cells, neurons and fireflies. In the mean-field limit, the probability density in phase satisfies a singular continuity equation prone to finite-time blow-up, for which very few theoretical results are available. With José A. Carrillo, Xu’an Dou and Zhennan Zhou, we have introduced a reformulation of the mean-field system based on the inverse distribution function seen in a dilated timescale. It allows to show a hidden contraction/expansion mechanism and to propose simple and rigorous proofs of the long-time behaviour, the existence of steady states, the rates of convergence and the occurence of finite time blow-up for a large class of monotone phase response functions.

27/11/2024 : Mathematical and Philosophical Foundations of Open Systems @PoliMi

Marco FalconiSeminar PoliMi 
Wednesday, November 27, 2024 - 9:00 - 12:30

Sala Consiglio (7th floor), D-Mat
Mathematics Department of PoliMi
Campus Leonardo, bd.14 "Nave".

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Program:

9:00 Karim Thebault (Bristol): “The Universe as an Open Quantum System”

9:45 Mike Cuffaro (Munich): “The Open Systems View (and Algebraic Quantum Field Theory)”

Coffee break

11:00 Sebastien Rivat (Munich): “The Open Systems View in Field Theory”

11:45 Michele Correggi (PoliMi): Quasi-classical Limit of a Spin Coupled to a Reservoir

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Description

The existence of open systems in physics poses outstanding philosophical issues. Indeed, while closed systems can be studied in isolation from the rest of the universe, open systems interact with the environment by exchanging heat and work, information, or matter. As such, open systems are subjected to changes due to uncontrollable external influences, which makes it challenging to precisely determine their properties. Since typical systems in the physical universe are not isolated, providing an adequate description of open systems lies at the heart of contemporary physics. In quantum theory, this issue is further complicated by the presence of entanglement between distant systems. Even more puzzling, at a cosmological scale, it is still a controversial matter whether the whole universe should be considered a closed or open system. The present workshop brings together philosophers and mathematical physicists to discuss the foundations of open systems both from a formal and a conceptual point of view. The invited speakers are Mike Cuffaro (Munich), Michele Correggi (PoliMi), Karim Thebault (Bristol) and Sebastien Rivat (Munich).

Organizing Committee: Antoine Brandelet, Massimo Moscolari and Giovanni Valente – Department of Mathematics, Politecnico di Milano

Participation is free of charge.

Funding: The conference is funded by Line 3 of the “Dipartimento di Eccellenza 2023-2027” on Mathematical features of quantum mechanics (Principal Investigator: Prof. Correggi), and by the Italian Ministry of University and Research within the PRIN 2022 project Analogical Reasoning in Contemporary Physical Theories (ID: 2022F4Z8YH, Principal Investigator: Giovanni Valente).