4 research outputs found
Relativistic calculations of isotope shifts in highly charged ions
The isotope shifts of forbidden transitions in Be- and B-like argon ions are
calculated. It is shown that only using the relativistic recoil operator can
provide a proper evaluation of the mass isotope shift, which strongly dominates
over the field isotope shift for the ions under consideration. Comparing the
isotope shifts calculated with the current experimental uncertainties indicates
very good perspectives for a first test of the relativistic theory of the
recoil effect in middle-Z ions
Quantum Cosmological Relational Model of Shape and Scale in 1-d
Relational particle models are useful toy models for quantum cosmology and
the problem of time in quantum general relativity. This paper shows how to
extend existing work on concrete examples of relational particle models in 1-d
to include a notion of scale. This is useful as regards forming a tight analogy
with quantum cosmology and the emergent semiclassical time and hidden time
approaches to the problem of time. This paper shows furthermore that the
correspondence between relational particle models and classical and quantum
cosmology can be strengthened using judicious choices of the mechanical
potential. This gives relational particle mechanics models with analogues of
spatial curvature, cosmological constant, dust and radiation terms. A number of
these models are then tractable at the quantum level. These models can be used
to study important issues 1) in canonical quantum gravity: the problem of time,
the semiclassical approach to it and timeless approaches to it (such as the
naive Schrodinger interpretation and records theory). 2) In quantum cosmology,
such as in the investigation of uniform states, robustness, and the qualitative
understanding of the origin of structure formation.Comment: References and some more motivation adde