Theoretical Physics
Theoretical Physics has a long standing tradition at Parma, since 60's of the past century. Parma contributed to the Physics of the Fundamental Interactions (QCD, Standard Model, QFT), Statistical Mechanics and General Relativity. Recent new lines include supercomputing code developments in nonperturbative quantum chromodynamics and relativistic astrophysics, complexity and string inspired quantum field theory.
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Fundamental interactions at high energy The study of elementary particle interactions at very high energy has been one of the most productive aspects of Theoretical Physics over the last century. Accelerator experiments continue to play a central role in the investigation of the fundamental laws of nature. The socalled Standard Model classifies and correctly describes all known particles, as well as their mutual interactions, which is considered as one of the major achievements of theoretical particle physics. The DIFEST group is nowadays focussed on the calculations related to a few aspects of the currently active experiments at the CERN LHC accelerator: diffractive phenomena, the investigation of the heavy (bottom and top) quarks, the physics of the neutrino, including precision calculations of the related cross sections. 

The theory that describes gravitational interactions and generalizes the newtonian formulation in many relevant contexts (astrophysics, cosmology and also in applied fields as metrology) is General Relativity. The gravitational field is interpreted geometrically and matter interacts dynamically with spacetime. The accurate theoretical study of extreme astrophysical objects (such as pulsar, xrays sources, neutron stars, black holes etc) requires General Relativity and the relevant equations for both matter and the electromagnetic fields. This is a formidable problem both theoretically and numerically. At present the only viable approach is by computer simulation. This approach requires appropriate architectures and dedicated numerical codes. In the last years our group at DIFEST has developed the relevant expertise and we investigate compact astrophysical objects which are the potential sources of gravitational waves that are the target of large scale experiments like the LIGO/VIRGO ones.


Quantum Field theory, Lattice Field Theory and Strings A consistent description of fundamental forces of Nature requires a theoretical formulation where Quantum Mechanics and Special Relativity are unified into the concept of quantum field. The unified quantum field implies the existence of all elementary particles and describes all the possible experimental events. Among the current topics explored by our research group at DIFEST we quote supercomputer studies of Quantum Field Theories on discrete lattices, where the mass of hadrons and the properties of quarkgluon plasma are numerically computed. Another major line is concerned with the mathematical properties of quantum field theories, as well as their developments as theories of extended objects (string theories), both with and without supersymmetries.


Statistical Physics, Quantum Mechanics and Complex Systems
The thermodynamical behavior of systems composed of a large number of particles (electrons, atoms, molecules, etc.) can be modelled statistically, in order to obtain their macroscopic properties starting from those of the single components. Complexity may emerge, typically over networks with nontrivial geometric and dynamical properties. That is, a complex unexpected behaviour may arise from many interacting simpler components that do not individually display that same behaviour. The research at DIFEST deals with topics both within and at the borders of Statistical Mechanics, Quantum Mechanics and Condensed Matter Physics with other fields (such as Biology and Social Sciences), studying both classical and quantum examples of complexity. 