The Experts below are selected from a list of 278061 Experts worldwide ranked by ideXlab platform
Benjamin G Levine - One of the best experts on this subject based on the ideXlab platform.
-
Wave Function continuity and the diagonal born oppenheimer correction at conical intersections
Journal of Chemical Physics, 2016Co-Authors: Garrett A Meek, Benjamin G LevineAbstract:We demonstrate that though exact in principle, the expansion of the total molecular Wave Function as a sum over adiabatic Born-Oppenheimer (BO) vibronic states makes inclusion of the second-derivative nonadiabatic energy term near conical intersections practically problematic. In order to construct a well-behaved molecular Wave Function that has density at a conical intersection, the individual BO vibronic states in the summation must be discontinuous. When the second-derivative nonadiabatic terms are added to the Hamiltonian, singularities in the diagonal BO corrections (DBOCs) of the individual BO states arise from these discontinuities. In contrast to the well-known singularities in the first-derivative couplings at conical intersections, these singularities are non-integrable, resulting in undefined DBOC matrix elements. Though these singularities suggest that the exact molecular Wave Function may not have density at the conical intersection point, there is no physical basis for this constraint. Inste...
-
Wave Function continuity and the diagonal born oppenheimer correction at conical intersections
Journal of Chemical Physics, 2016Co-Authors: Garrett A Meek, Benjamin G LevineAbstract:We demonstrate that though exact in principle, the expansion of the total molecular Wave Function as a sum over adiabatic Born-Oppenheimer (BO) vibronic states makes inclusion of the second-derivative nonadiabatic energy term near conical intersections practically problematic. In order to construct a well-behaved molecular Wave Function that has density at a conical intersection, the individual BO vibronic states in the summation must be discontinuous. When the second-derivative nonadiabatic terms are added to the Hamiltonian, singularities in the diagonal BO corrections (DBOCs) of the individual BO states arise from these discontinuities. In contrast to the well-known singularities in the first-derivative couplings at conical intersections, these singularities are non-integrable, resulting in undefined DBOC matrix elements. Though these singularities suggest that the exact molecular Wave Function may not have density at the conical intersection point, there is no physical basis for this constraint. Instead, the singularities are artifacts of the chosen basis of discontinuous Functions. We also demonstrate that continuity of the total molecular Wave Function does not require continuity of the individual adiabatic nuclear Wave Functions. We classify nonadiabatic molecular dynamics methods according to the constraints placed on Wave Function continuity and analyze their formal properties. Based on our analysis, it is recommended that the DBOC be neglected when employing mixed quantum-classical methods and certain approximate quantum dynamical methods in the adiabatic representation.
Y Kuramashi - One of the best experts on this subject based on the ideXlab platform.
-
relation between scattering amplitude and bethe salpeter Wave Function in quantum field theory
Physical Review D, 2017Co-Authors: Takeshi Yamazaki, Y KuramashiAbstract:We reexamine the relations between the Bethe-Salpeter (BS) Wave Function of two particles, the on-shell scattering amplitude, and the effective potential in quantum filed theory. It is emphasized that there is an exact relation between the BS Wave Function inside the interaction range and the scattering amplitude, and the reduced BS Wave Function, which is defined in this article, plays an essential role in this relation. Based on the exact relation, we show that the solution of Schr\"odinger equation with the effective potential gives us a correct on-shell scattering amplitude only at the momentum where the effective potential is calculated, while wrong results are obtained from the Schr\"odinger equation at general momenta. We also discuss about a momentum expansion of the reduced BS Wave Function and an uncertainty of the scattering amplitude stemming from the choice of the interpolating operator in the BS Wave Function. The theoretical conclusion obtained in this article could give hints to understand the inconsistency observed in lattice QCD calculation of the two-nucleon channels with different approaches.
-
relation between scattering amplitude and bethe salpeter Wave Function in quantum field theory
Physical Review D, 2017Co-Authors: Takeshi Yamazaki, Y KuramashiAbstract:We discuss an exact relation between the two-particle scattering amplitude and the Bethe-Salpeter (BS) Wave Function inside the interaction range in quantum field theory. In the relation the reduced BS Wave Function defined by the BS Wave Function plays an essential role. Through the relation the on-shell and half off-shell amplitudes can be calculated. We also show that the solution of Schrodinger equation with the effective potential determined from the BS Wave Function gives a correct on-shell scattering amplitude only at the momentum where the effective potential is determined. Furthermore we discuss a derivative expansion of the reduced BS Wave Function and a condition to obtain results independent of the interpolating operators in the time-dependent HALQCD method.
Hsiangnan Li - One of the best experts on this subject based on the ideXlab platform.
-
joint resummation for pion Wave Function and pion transition form factor
Journal of High Energy Physics, 2014Co-Authors: Yuelong Shen, Hsiangnan Li, Yuming WangAbstract:We construct an evolution equation for the pion Wave Function in the k T factorization formalism, whose solution sums the mixed logarithm ln x ln k T to all orders, with x (k T ) being a parton momentum fraction (transverse momentum). This joint resummation induces strong suppression of the pion Wave Function in the small x and large b regions, b being the impact parameter conjugate to k T , and improves the applicability of perturbative QCD to hard exclusive processes. The above effect is similar to those from the conventional threshold resummation for the double logarithm ln2 x and the conventional k T resummation for ln2 k T . Combining the evolution equation for the hard kernel, we are able to organize all large logarithms in the γ * π 0 → γ scattering, and to establish a scheme-independent k T factorization formula. It will be shown that the significance of next-to-leading-order contributions and saturation behaviors of this process at high energy differ from those under the conventional resummations. It implies that QCD logarithmic corrections to a process must be handled appropriately, before its data are used to extract a hadron Wave Function. Our predictions for the involved pion transition form factor, derived under the joint resummation and the input of a non-asymptotic pion Wave Function with the second Gegenbauer moment a 2 = 0.05, match reasonably well the CLEO, BaBar, and Belle data.
Yuki Yamazaki - One of the best experts on this subject based on the ideXlab platform.
-
de broglie bohm interpretation for Wave Function of reissner nordstrom de sitter black hole
International Journal of Modern Physics A, 2000Co-Authors: Masakatsu Kenmoku, Hiroto Kubotani, Eiichi Takasugi, Yuki YamazakiAbstract:We study the canonical quantum theory of the spherically symmetric geometry with the cosmological constant and the electromagnetic field. We obtain a solution of the Wheeler–DeWitt equation for the geometrical variables and investigate the Wave Function from a viewpoint of the de Broglie–Bohm interpretation of the ordinary quantum mechanics. The de Broglie–Bohm interpretation introduces deterministic rigid trajectories on the minisuperspace without any outside observers nor the collapse of the Wave Function. It is shown that the Wave Function does not only correspond to the classical Reissner–Nordstrom–de Sitter black hole in the semiclassical region, but it also represents quantum geometrical fluctuations near the black hole horizon and the cosmological one. The result suggests that the semiclassical gravity on which the Hawking radiation is based is broken near the horizons.
-
de broglie bohm interpretation for Wave Function of reissner nordstrom de sitter black hole
arXiv: General Relativity and Quantum Cosmology, 1998Co-Authors: Masakatsu Kenmoku, Hiroto Kubotani, Eiichi Takasugi, Yuki YamazakiAbstract:We study the canonical quantum theory of the Reissner-Nordstrom-de Sitter black hole(RNdS). We obtain an exact general solution of the Wheeler-DeWitt equation for the spherically symmetric geometry with electro-magnetic field. We investigate the Wave Function form a viewpoint of the de Broglie-Bohm interpretation. The de Broglie-Bohm interpretation introduces a rigid trajectory on the minisuperspace without assuming an outside observer or causing collapse of the Wave Function. In our analysis, we obtain the boundary condition for the Wave Function which corresponds to the classical RNdS black hole and describe the quantum fluctuations near the horizons quantitatively.
Garrett A Meek - One of the best experts on this subject based on the ideXlab platform.
-
Wave Function continuity and the diagonal born oppenheimer correction at conical intersections
Journal of Chemical Physics, 2016Co-Authors: Garrett A Meek, Benjamin G LevineAbstract:We demonstrate that though exact in principle, the expansion of the total molecular Wave Function as a sum over adiabatic Born-Oppenheimer (BO) vibronic states makes inclusion of the second-derivative nonadiabatic energy term near conical intersections practically problematic. In order to construct a well-behaved molecular Wave Function that has density at a conical intersection, the individual BO vibronic states in the summation must be discontinuous. When the second-derivative nonadiabatic terms are added to the Hamiltonian, singularities in the diagonal BO corrections (DBOCs) of the individual BO states arise from these discontinuities. In contrast to the well-known singularities in the first-derivative couplings at conical intersections, these singularities are non-integrable, resulting in undefined DBOC matrix elements. Though these singularities suggest that the exact molecular Wave Function may not have density at the conical intersection point, there is no physical basis for this constraint. Inste...
-
Wave Function continuity and the diagonal born oppenheimer correction at conical intersections
Journal of Chemical Physics, 2016Co-Authors: Garrett A Meek, Benjamin G LevineAbstract:We demonstrate that though exact in principle, the expansion of the total molecular Wave Function as a sum over adiabatic Born-Oppenheimer (BO) vibronic states makes inclusion of the second-derivative nonadiabatic energy term near conical intersections practically problematic. In order to construct a well-behaved molecular Wave Function that has density at a conical intersection, the individual BO vibronic states in the summation must be discontinuous. When the second-derivative nonadiabatic terms are added to the Hamiltonian, singularities in the diagonal BO corrections (DBOCs) of the individual BO states arise from these discontinuities. In contrast to the well-known singularities in the first-derivative couplings at conical intersections, these singularities are non-integrable, resulting in undefined DBOC matrix elements. Though these singularities suggest that the exact molecular Wave Function may not have density at the conical intersection point, there is no physical basis for this constraint. Instead, the singularities are artifacts of the chosen basis of discontinuous Functions. We also demonstrate that continuity of the total molecular Wave Function does not require continuity of the individual adiabatic nuclear Wave Functions. We classify nonadiabatic molecular dynamics methods according to the constraints placed on Wave Function continuity and analyze their formal properties. Based on our analysis, it is recommended that the DBOC be neglected when employing mixed quantum-classical methods and certain approximate quantum dynamical methods in the adiabatic representation.
