Related papers: Crossed-boson exchange contribution and Bethe-Salp…
We calculate at two-loop order the complex-valued scattering amplitude related to the twice-iterated scalar-isovector boson-exchange between nucleons. In comparison to the once-iterated boson-exchange amplitude it shows less dependence on…
A new formulation for the study of interacting bosons on a lattice is introduced. This approach is used to give analytical expressions for the Mott insulating lobes in the phase diagram and to calculate the density-density correlation…
The exclusive deuteron break-up reaction is analyzed within a covariant approach based on the Bethe-Salpeter equation with realistic meson-exchange interaction. Relativistic effects in the cross section, tensor analyzing power and…
A two-body interaction or force between quantum particles is ubiquitous in nature, and the microscopic description in terms of the bare two-body interaction is the basis for quantitatively describing interacting few- and many-body systems.…
Nucleon transfer reactions in deuteron-deuteron collisions at energies above the three- and four-body breakup threshold are described using exact four-body equations for transition operators that are solved in the momentum-space framework.…
An enhanced binding of an $N$-particle system interacting through a scalar bose field is investigated, where $N\geq 2$. It is not assumed that this system has a ground state for a zero coupling. It is shown, however, that there exists a…
The Bethe-Salpeter equation is a non-perturbative, relativistic and covariant description of two-body bound states. We derive the classical Bethe-Salpeter equation for two massive point particles (with or without spin) in a bound…
We investigate the nonrelativistic reduction of the Bethe-Salpeter amplitude for the deuteron electrodisintegration near threshold energies. To this end, two assumptions have been used in the calculations: 1) the static approximation and 2)…
We rigorously discuss the large-$N$ thermodynamics of a Bose gas with a short-range two-body potential. Considering the system as a mixture of $N$ identical components with symmetrical interaction we calculated numerically the temperature…
We calculate the two-pion exchange potential between a heavy meson and a heavy baryon. We find this potential is as strong as the one-pion exchange potential between two heavy mesons and is enough to bind $\Lambda_b-\bar B$. Though our…
As well known, the spectrum of a non-relativistic two-body system interacting by the Coulomb potential is the Balmer series $E_n=\frac{\alpha^2m}{4n^2}$ produced by the Schr\"odinger equation. In 1954, Wick and Cutkosky have found, in the…
Quantum energy transfer in a chain of two-level (spin) units, connected at its ends to two thermal reservoirs, is analyzed in two limits: (i) In the off-resonance regime, when the characteristic subsystem excitation energy gaps are larger…
We present a new method of obtaining nonlinear integral equations characterizing the thermodynamics of one-dimensional multi-component gases interacting via a delta-function potential. In the case of the repulsive two-component Bose gas we…
We study the rotational properties of a two-component Bose-Einstein condensed gas of distinguishable atoms which are confined in a ring potential using both the mean-field approximation, as well as the method of diagonalization of the…
The two-fermion bound system is an attractive subject of atomic and sub-atomic physics. Despite these systems are rather simple the study of two-particle bound states is challenging and still remains a source of progress in quantum theory.…
We establish bounds on the energy of a system of N identical bosons bound by attractive pair potentials and obeying the semirelativistic Salpeter equation. The lower bound is provided by a `reduction', with the aid of Jacobi relative…
We perform a systematic study of the possible molecular states composed of a pair of heavy mesons such as $D^{(*)}D^{(*)}$, $D^{(*)}\bar{D}^{(*)}$ in the framework of the one-boson-exchange model. The exchanged bosons include the…
We present a method to compute optical spectra and exciton binding energies of molecules and solids based on the solution of the Bethe-Salpeter equation (BSE) and the calculation of the screened Coulomb interaction in finite field. The…
In the framework of the interacting boson model the three transitional regions (rotational-vibrational, rotational-$\gamma$-unstable and, vibrational-$\gamma$-unstable transitions) are reanalyzed. A new kind of plot is presented for…
In this work, we extend the analysis of interacting bosons at 2D-1D dimensional crossover for finite size and temperature by using field-theory approach (bosonization) and quantum Monte Carlo simulations. Stemming from the fact that finite…