This article argues that there is a consistent description of gravitationally collapsed bodies, including neutron stars above the Tolman-Oppenheimer-Volkoff mass and also supermassive galactic centres, according to which collapse stops before the object reaches its gravitational radius, the density reaching a maximum close to the surface and then decreasing towards the centre. Models for such s...

The finite-temperature dynamics of WAu12, incorporating both electronic and structural effects, is studied using a density-functional-based Born-Oppenheimer molecular dynamics method. Molecular dynamics simulations for monomolecular WAu12 suggest a surface-melting-type behaviour of the angular degrees of freedom between 366 and 512 K. Thermally averaged electron density-of-states of WAu12 are c...

Time-reversible ab initio molecular dynamics based on a lossless multichannel decomposition for the integration of the electronic degrees of freedom [Phys. Rev. Lett. 97, 123001 (2006)] is explored. The authors present a lossless time-reversible density matrix molecular dynamics scheme. This approach often allows for stable Hartree-Fock simulations using only one single self-consistent field cy...

Although the concept of a potential energy curve (PEC) originates from the outgrowth of the Born-Oppenheimer (BO) approximation, we propose the application of analysis methods for the physical PEC with non-Born-Oppenheimer (non-BO) wave functions. A numerical examination was performed with the highly accurate non-BO vibronic wave functions of hydrogen molecular ion, which were obtained in our p...

Akinori Igarashi1 and C. D. Lin2 1Department of Applied Physics, Faculty of Engineering, Miyazaki University, Miyazaki, 889-2192, Japan 2Department of Physics, Cardwell Hall, Kansas State University, Manhattan, Kansas 66506 (Received 18 May 1999) Cross sections for the nonresonant charge transfer process D 1 H 1s ! D 1s 1 H at low energies are calculated in hyperspherical coordinates. The metho...

Based upon the identification of 38 white dwarfs with halo kinematics, in a survey covering 10% of the sky near the south Galactic pole, Oppenheimer et al. (1) argue that at least 2% of the dark matter in the Galaxy has now been detected directly. Put into context, the Oppenheimer et al. result implies that the stellar remnant mass of the halo may be comparable to that of the entire disk of our...

The various recent studies on the application of the Born-Oppenheimer approach in a closed gravity matter system is examined. It is pointed out that the Born-Oppenheimer approach in the absence of an a priori time is likely to yield potentially new results.

where R is the set of nuclear coordinates and r is the set of electronic coordinates. If spin-orbit effects are important, they can be added through a spin-orbit operator Ĥso. Unfortunately, the V̂eN(r,R) term prevents us from separating Ĥ into nuclear and electronic parts, which would allow us to write the molecular wavefunction as a product of nuclear and electronic terms, Ψ(r,R) = Ψ(r)χ(R). W...