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Commercial Incentives in Academia
This paper investigates the effects of monetary rewards from commercialisation on the pattern of research. We build a simple repeated model of a researcher capable to obtain innovative ideas. We analyse how academic and market incentives affect the allocation of the researcher’s time between research and development. We argue, however, that technology transfer objectives also affect the choice of research projects. Although commercialisation incentives reduce the time spent in research, they might also induce researchers to conduct research that is more basic in nature, contrary to what the “skewing problem” would presage. Monetary rewards induce a more intensive search for (ex-post) path-breaking innovations, which are more likely to be generated through (ex-ante) basic research programs. These results are shown to hold even if development delays publication
The shape of the baryon in a covariant spectator quark model
Using a covariant spectator quark model that describes the recent lattice QCD
data for the electromagnetic form factors and all available
experimental data on transitions, we analyze the charge
and magnetic dipole distributions of the baryon and discuss its shape.
We conclude that the quadrupole moment of the is a good indicator of
the deformation and that the charge distribution has an oblate
shape. We also calculate transverse moments and find that they do not lead to
unambiguous conclusions about the underlying shape.Comment: Extended introduction, references added, other small modifications.
To appear in Phys. Rev. D. 14 pages, 8 figure
Nucleon Resonance Effects in near Threshold
The role of the low lying nucleon resonances beyond the in the
reaction near threshold is shown to be numerically significant
by a calculation, which takes into account the pion re-scattering contribution
described by chiral perturbation theory and the short-range mechanisms that are
implied by the nucleon-nucleon interaction model. The intermediate N(1440)
(P) resonance is excited by the short-range exchange mechanisms, while
the N(1535) () and N(1520) () resonances are excited by
and meson exchange, respectively. The increases the calculated
cross section, whereas the and resonances decrease it. The
calculation takes full account of the initial and final state interactions.Comment: Revised accepted versio
Off-Mass-Shell N Scattering and
We adapt the off-shell N amplitude of the Tucson-Melbourne three-body
force to the half-off-shell amplitude of the pion rescattering contribution to
near threshold. This {\em pion} rescattering contribution,
together with the impulse term, provides a good description of the data when
the half-off-shell amplitude is linked to the phenomenological invariant
amplitudes obtained from meson factory N scattering data.Comment: 3 pages, contributed to STORRI99, Bloomington, Indiana, September
199
Can the System be Bound?
Motivated by the -hypernuclear states reported in ()
experiments, we have explored the possibility that there exists a
particle-stable bound state. For the J\"ulich \~A
hyperon-nucleon, realistic-force model, our calculations yield little reason to
expect a positive-parity bound state in either the or the channels.Comment: 6 pages in LaTeX, 1 Figure (appended in uuencoded tar-compressed
PostScript format), College of William and Mary preprint WM-94-103, LANL
preprint LA-UR-94-023
Metastable States in High Order Short-Range Spin Glasses
The mean number of metastable states in higher order short-range spin
glasses is estimated analytically using a variational method introduced by
Tanaka and Edwards for very large coordination numbers. For lattices with small
connectivities, numerical simulations do not show any significant dependence on
the relative positions of the interacting spins on the lattice, indicating thus
that these systems can be described by a few macroscopic parameters. As an
extremely anisotropic model we consider the low autocorrelated binary spin
model and we show through numerical simulations that its landscape has an
exceptionally large number of local optima
A covariant constituent-quark formalism for mesons
Using the framework of the Covariant Spectator Theory (CST) [1] we are
developing a covariant model formulated in Minkowski space to study mesonic
structure and spectra. Treating mesons as effective states, we
focused in [2] on the nonrelativistic bound-state problem in momentum space
with a linear confining potential. Although integrable, this kernel has
singularities which are difficult to handle numerically. In [2] we reformulate
it into a form in which all singularities are explicitely removed. The
resulting equations are then easier to solve and yield accurate and stable
solutions. In the present work, the same method is applied to the relativistic
case, improving upon the results of the one-channel spectator equation (1CSE)
given in [3].Comment: 6 pages, 5 figures, Presented at EEF70, Workshop on Unquenched Hadron
Spectroscopy: Non-Perturbative Models and Methods of QCD vs. Experimen
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