73,896 research outputs found
Calculation of accurate permanent dipole moments of the lowest states of heteronuclear alkali dimers using extended basis sets
The obtention of ultracold samples of dipolar molecules is a current
challenge which requires an accurate knowledge of their electronic properties
to guide the ongoing experiments. In this paper, we systematically investigate
the ground state and the lowest triplet state of mixed alkali dimers (involving
Li, Na, K, Rb, Cs) using a standard quantum chemistry approach based on
pseudopotentials for atomic core representation, gaussian basis sets, and
effective terms for core polarization effects. We emphasize on the convergence
of the results for permanent dipole moments regarding the size of the gaussian
basis set, and we discuss their predicted accuracy by comparing to other
theoretical calculations or available experimental values. We also revisit the
difficulty to compare computed potential curves among published papers, due to
the differences in the modelization of core-core interaction.Comment: accepted to J. Chem. Phy
Sound separation probe
Probe separates sound waves from turbulent flow pressure fluctuations in ducted airstreams by using principle that sound waves and turbulent flow pressure perturbations travel at different velocities
Comment on "General Method to Determine Replica Symmetry Breaking Transitions"
In a recent letter Marinari et al [Phys. Rev. Lett. 81, 1698 (1998)]
introduced a new method to study spin glass transitions and argued that by
probing replica symmetry (RS) as opposed to time reversal symmetry (TRS), their
method unambiguously shows that replica symmetry breaking (RSB) occurs in
short-range spin glasses. In this comment we show that while the new method is
indeed useful for studying transitions in systems where TRS is absent (such as
the p-spin model studied by them), the conclusion that it shows the existence
of RSB in short-range spin glasses is wrong.Comment: 1 page, RevTe
A pseudo-potential analog for zero-range photoassociation and Feshbach resonance
A zero-range approach to atom-molecule coupling is developed in analogy to
the Fermi-Huang pseudo-potential treatment of atom-atom interactions. It is
shown by explicit comparison to an exactly-solvable finite-range model that
replacing the molecular bound-state wavefunction with a regularized
delta-function can reproduce the exact scattering amplitude in the
long-wavelength limit. Using this approach we find an analytical solution to
the two-channel Feshbach resonance problem for two atoms in a spherical
harmonic trap
From an axiological standpoint
I maintain that intrinsic value is the fundamental concept of axiology. Many contemporary philosophers disagree; they say the proper object of value theory is final value. I examine three accounts of the nature of final value: the first claims that final value is non‐instrumental value; the second claims that final value is the value a thing has as an end; the third claims that final value is ultimate or non‐derivative value. In each case, I argue that the concept of final value described is either identical with the classical notion of intrinsic value or is not a plausible candidate for the primary concept of axiology
- …