Finite nuclei in many body theory

An exact method of solution of the Goldstone equation for reaction matrix for finite nuclei is presented. The method can be applied to any double-magic nucleus if the two-nucleon potential does not contain a hard core. The basic properties of the nucleus, i.e. binding energy, nucleon densities, r.m.s. and formfactor are expressed with the help of reaction matrix and certain auxiliary quantities and related to the centre of mass motion.The author would like to express his gratitude to the Rutherford High Energy Laboratory for the possibility to perform this study and especially to Dr G. H.Stafford, Dr G.Manning, Dr R. J. N.Phillips and Dr C. J.Batty for their encouraging interest.     

On the relativistic theory of tunneling

A relativistic generalization of the semiclassical theory of tunneling and multiphoton ionization of atoms and ions in the field of a high-intensity electromagnetic wave with linear, circular, and elliptic polarization is constructed. The exponential factor in the ionization probability is calculated for arbitrary values of adiabaticity parameter γ. In the case of low-frequency laser radiation, an asymptotically exact formula is derived for the ionization rate of the s atomic level, including the Coulomb, spin, and adiabatic corrections and the preexponential factor.     

Many body theory of photoemission in the quadratic response formalism

Many body Green's function techniques are applied to show that the three current correlation function relating the one photon photoemission current to the applied external field may be expressed by one and two particle correlation properties only for arbitrary many body interactions. An analysis of the double time derivative of the three current correlation function leads to a generalization for arbitrary many body interaction of a formula frequently used for calculations of the photocurrent in the independent electron model. Implications are discussed for the case that only electrostatic electron-electron interactions are present.     

On the relativistic generalization of Keldysh ionization theory

Relativistic generalization of the semiclassical theory of tunnel and multiphoton ionization of atoms and ions in the field of a high-intensity electromagnetic wave (Keldysh theory) with linear and elliptic polarizations is developed. The exponential factor in the ionization rate of relativistic bound state is calculated for arbitrary values of the adiabaticity parameter γ. In the case of low-frequency laser radiation, $\gamma \ll 1$, the asymptotically exact formula is derived for the ionization rate of atomic s-level, including the Coulomb, spin and adiabatic corrections and the pre-exponential factor. The ionization rate of the ground state of a hydrogen-like atoms (ions) with $Z\lesssim 100$ is calculated, depending on laser intensity and ellipticity of radiation.     

Origin of the pseudospin symmetry in the relativistic formalism

The grounds on which the nuclear pseudospin symmetry (PSS) is supposed to be based are analysed within the relativistic mean-field framework. A connection between the mechanisms responsible for the spin-orbit and pseudospin-orbit splittings is shown. The nature of the PSS is investigated through an extended Dirac equation which allows a generalization of the PSS breaking term. It is shown that the PSS breaking in real nuclei can be explained as a result of a non-perturbative transformation from non-physical solutions of the Dirac equation, which satisfy exactly the PSS, to the physical ones. The PSS breaking term produces important, though qualitatively similar, effects on both states of a pseudospin-orbit doublet. The similarity of these effects increases with the number of nodes of the small component of the Dirac spinor of these states.Received: 28 April 2003, Revised: 30 October 2003, Published online: 18 June 2004PACS: 24.10.Jv Relativistic models - 21.60.Cs Shell model - 21.10.Pc Single-particle levels and strength functions - 24.80. + y Nuclear tests of fundamental interactions and symmetries     

Redefined relativistic thermodynamics based on the Nakamura formalism

By using the concept of volume introduced by Nakamura in relativistic thermodynamics, a relativistic thermodynamical theory is proposed. A comparison is presented between the new theory, the van Kampen covariant theory and the Rohrlich proposal. A relativistic thermometer is proposed by using the Unruh-DeWitt detector.     

On relativistic kinetic gas theory: XV. The Ritz method in relativistic Boltzmann theory

The transport coefficients of a multicomponent gas mixture are approximated by means of a variational technique. It is shown that the procedure is equivalent to a more heuristic method developed earlier.     

Disappearance of unlinked graphs in field theory and the many body problem

Using the time path method introduced in the non-equilibrium many-body problem the contribution to perturbation series in field theory or many-body theory from unlinked graphs is shown to vanish identically due to a causality principle.     

On a modification of the boundary-state formalism in off-shell string theory

We examine the application of boundary states in computing amplitudes in off-shell open string theory. We find a straightforward generalization of a boundary state which produces the correct matrix elements with on-shell closed string states.     

On the relativistic field theory model of the deuteron II

The relativistic field theory model of the deuteron suggested previously is revised and applied to the calculation of the cross sections of the low-energ radiative neutron-proton capture n + p → D + γ and the low-energy two-proton fusion p + p → D + e⁺ + ν_e. For the low-energy data and the potential model prediction. In the case of the two-proton fusion the cross section obtained is 2.9 times as much as that given by the potential approach. The obtained result is discussed in connection with the solar neutrino problem.     

On the adhesion theory of solids in terms of the dielectric formalism

The calculated dependences for computing the energy and strength of the ideal adhesion for solids (metals, semiconductors, and dielectrics) have been obtained in terms of the dielectric formalism. The inclusion of the linear and quadratic dispersions of surface plasmons provides a good agreement of the calculated values with the available data.     

On the geometric and algebraic foundation of the spinor formalism and the application to relativistic field equations

The Hilbert calculus of segments plays an important role in the axiomatic foundation of the Euclidean geometry, as the relationship to some fundamental agebraic structures can be made more apparent. An extension of the Hilbert calculus to the field of the quaternionsU2 or biquaternionsU4 leads to some new aspects on the spinor formalism. By that, a geometrical interpretation of the Dirac equation is obtained. Including the torsion of the Minkowski space (Cartan geometry), the affine connection of the spinor spaceU4 also can be interpreted with the help of a generalized Hilbert calculus. These considerations lead to a simple geometrical access to the nonlinear spinor theory, proposed by Ivanenko, Heisenberg, Dürr, etc.     

The Brillouin-Wigner expansion in a relativistic two-body formalism

The Brillouin-Wigner perturbation theory is used to precisely calculate the energy levels of hydrogen-like systems.     

On the Thomas precession in the classical theory of relativistic radiation

It is demonstrated that the radiation of the angular momentum power of electromagnetic field is directly proportional to the Thomas precession frequency. Thereby the dynamical aspect of origin of this phenomenon is established for the first time.     

Measurement theory in the Lax-Phillips formalism

It is shown that the application of the Lax-Phillips scattering theory to quantum mechanics provides a natural framework for the realization of the ideas of the Many-Hilbert-Space theory of Machida and Namiki to describe the development of decoherence in the process of measurement. We show that if the quantum mechanical evolution is pointwise in time, then decoherence occurs only if the Hamiltonian is time-dependent. If the evolution is not pointwise in time (as in Liouville space), then the decoherence may occur even for closed systems. These conclusions apply as well to the general problem of mixing of states.