Research
My research work is in general in the field of nonequilibrium statistical
physics and theory of complex systems.
More in detail, I currently focus on the following topics:
- Regularities and universality in large-scale social phenomena
- Statistical physics approach to social dynamics
- Nonequilibrium dynamics on complex topologies
Regularities and universality in large-scale social phenomena
In social phenomena every individual interacts with
a limited number of peers, usually negligible as compared with
the total number of people in the system.
In spite of that, human societies are characterized by stunning global
regularities.
There are transitions from disorder to order, like the spontaneous
emergence of a common language/culture or the creation
of consensus about a specific topic. There are examples of
scaling, as in the distribution of votes in elections.
In order to understand the nature and the origin of such regularities
it is crucial to characterize them in a quantitatively precise way,
looking in particular for features that are universal, i.e. shared
by different phenomena. The identification of such features is
fundamental for devising sensible simple models able to reproduce
the empirical observations and suitable for theoretical investigation.
Statistical physics approach to social dynamics
In recent years it has become widely recognized that many large-scale
phenomena observed in social systems are the "macroscopic" complex
effect of the "microscopic" simple behavior of a large number of
interacting agents.
This has led social scientists to the introduction of elementary
models of social behavior (cellular automata, agent-based models).
Many of these models are somehow relatives of models that have been
introduced in modern traditional statistical physics, and it is natural
to approach them using the same concepts and tools that have been
successfully applied in physics.
Nonequilibrium dynamics on complex topologies
Dynamical processes have been studied for decades on regular lattices
and their behavior is generally very well understood.
When such processes take place on a complex network, what is the effect
of the disordered interaction pattern on their phenomenology?
In recent years I have been in particular involved in the investigation
of the effect of the absence of a characteristic scale in scale-free
networks on the behavior of the contact process. Interesting questions
concern the validity of mean-field theory and the application of
finite-size scaling theory.
Other research interests
I have interest in many other topics, including:
- Community structure of complex networks
- Non equilibrium surface growth
- Instabilities and pattern formation in epitaxial growth
- Phase-ordering dynamics