We have recently constructed a many-body theory for composite excitons, in which the possible carrier exchanges between N excitons can be treated exactly through a set of dimensionless “Pauli scatterings” between two excitons. Many-body effects with excitons turn out to be rather simple because excitons are the exact one-electron-hole-pair eigenstates of the semiconductor Hamiltonian, thus form...

Ab-initio predictions of nuclei with masses up to A⇠100 or more are becoming possible thanks to novel advances in computations and in the formalism of many-body physics. Some of the most fundamental issues include how to deal with many-nucleon interactions, how to calculate degenerate—open shell—systems, and pursuing ab-initio approaches to reaction theory. Self-consistent Green’s function (SCG...

I review the description of the electroweak nuclear response at large momentum transfer within nonrelativistic many-body theory. Special consideration is given to the effects of final state interactions, which are known to be large in both inclusive and semi-inclusive processes. The results of theoretical calculations of electron-nucleus scattering observables are compared to the data, and the ...

On the atomic scale, Molecular Dynamic (MD) Simulation of Nano Al cluster impact on Al (100) substrate surface has been carried out for energies of 1-20 eV/atom to understand quantitatively the interaction mechanisms between the cluster atoms and the substrate atoms. The many body Embedded Atom Method (EAM) was used in this simulation. We investigated the maximum substrate temperature Tmax  and...

The ground states of all even-even nuclei have angular momentum, I, equal to zero, I = 0, and positive parity, π = +. This feature was believed to be a consequence of the attractive short-range interaction between nucleons. However, in the presence of two-body random interactions, the predominance of I = 0 ground states (0 g.s.) was found to be robust both for bosons and for an even number of f...

We investigate whether coherent flavor conversion of neutrinos in a neutrino background is substantially modified by many-body effects, with respect to the conventional one-particle effective description. We study the evolution of a system of interacting neutrino plane waves in a box. Using its equivalence to a system of spins, we determine the character of its behavior completely analytically....