42 research outputs found
Planckian Scattering Beyond the Eikonal Approximation in the Functional Approach
In the framework of functional integration the non-leading terms to leading
eikonal behavior of the Planckian-energy scattering amplitude are calculated by
the straight-line path approximation. We show that the allowance for the
first-order correction terms leads to the appearance of retardation effect. The
singular character of the correction terms at short distances is also noted,
and they may be lead ultimately to the appearance of non-eikonal contributions
to the scattering amplitudes.Comment: 15 pages, no figure
Von Neumann's Quantization of General Relativity
Von Neumann's procedure is applied for quantization of General Relativity. We
quantize the initial data of dynamical variables at the Planck epoch, where the
Hubble parameter coincides with the Planck mass. These initial data are defined
via the Fock simplex in the tangent Minkowskian space-time and the Dirac
conformal interval. The Einstein cosmological principle is applied for the
average of the spatial metric determinant logarithm over the spatial volume of
the visible Universe. We derive the splitting of the general coordinate
transformations into the diffeomorphisms (as the object of the second N\"other
theorem) and the initial data transformations (as objects of the first N\"other
theorem). Following von Neumann, we suppose that the vacuum state is a quantum
ensemble. The vacuum state is degenerated with respect to quantum numbers of
non-vacuum states with the distribution function that yields the Casimir effect
in gravidynamics in analogy to the one in electrodynamics. The generation
functional of the perturbation theory in gravidynamics is given as a solution
of the quantum energy constraint. We discuss the region of applicability of
gravidynamics and its possible predictions for explanation of the modern
observational and experimental data.Comment: 14 pages, updated version with extended discussio
High Energy Scattering in the Quasi-Potential Approach
Asymptotic behavior of the scattering amplitude for two scalar particles by
scalar, vector and tensor exchanges at high energy and fixed momentum transfers
is reconsidered in quantum field theory. In the framework of the
quasi-potential approach and the modified perturbation theory a systematic
scheme of finding the leading eikonal scattering amplitudes and its corrections
are developed and constructed.The connection between the solutions obtained by
quasi-potential and functional approaches is also discussed.The first
correction to leading eikonal amplitude is found. Keywords: Eikonal scattering
theory, Quantum gravity.Comment: 18 pages. arXiv admin note: substantial text overlap with
arXiv:0804.343