21,903 research outputs found
Nuclear Dynamics with the Sky3D code
A description is presented of how to use the Sky3D time-dependent
Hartree-Fock code to calculate giant monopole resonances. This requires
modification to the code, and a step-by-step guide of how to make the necessary
modification is given. An example of how to analyse the output of the code to
obtain quantities of physics interest is included. Together, the modifications
and the post-processing are intended to serve as a typical example of how the
code, which was designed to be extendable to particular users' needs, can be
extended.Comment: submitted to Proceedings of the International Workshop on Nuclear
Theory 33 (Rila, Bulgaria
Exploring arbitrarily high orders of optimized perturbation theory in QCD with nf -> 16.5
Perturbative QCD with nf flavours of massless quarks becomes simple in the
hypothetical limit nf -> 16.5, where the leading beta-function coefficient
vanishes. The Banks-Zaks (BZ) expansion in a0=(8/321)(16.5-nf) is
straightforward to obtain from perturbative results in MSbar or any
renormalization scheme (RS) whose nf dependence is `regular.' However,
`irregular' RS's are perfectly permissible and should ultimately lead to the
same BZ results. We show here that the `optimal' RS determined by the Principle
of Minimal Sensitivity does yield the same BZ-expansion results when all orders
of perturbation theory are taken into account. The BZ limit provides an arena
for exploring optimized perturbation theory at arbitrarily high orders. These
explorations are facilitated by a `master equation' expressing the optimization
conditions in the fixed-point limit. We find an intriguing strong/weak coupling
duality a -> a*^2/a about the fixed point a*.Comment: 32 pages, 4 figure
The lambda Phi^4 Miracle: lattice data and the zero-point potential
Recent lattice data for the effective potential of lambda Phi^4 theory fits
the massless one-loop formula with amazing precision. Any corrections are at
least 100 times smaller than is reasonable, perturbatively. This is strong
evidence for the "exactness conjecture" of Consoli and Stevenson.Comment: 6 pages, LaTe
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