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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
High-precision covariant one-boson-exchange potentials for np scattering below 350 MeV
All realistic potential models for the two-nucleon interaction are to some
extent based on boson exchange. However, in order to achieve an essentially
perfect fit to the scattering data, characterized by a chi2/Ndata ~ 1, previous
potentials have abandoned a pure one boson-exchange mechanism (OBE). Using a
covariant theory, we have found a OBE potential that fits the 2006 world np
data below 350 MeV with a chi2/Ndata = 1.06 for 3788 data. Our potential has
fewer adjustable parameters than previous high-precision potentials, and also
reproduces the experimental triton binding energy without introducing
additional irreducible three-nucleon forces.Comment: 4 pages; revised version with augmented data sets; agrees with
published versio
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
Dynamical diversity and metastability in a hindered granular column near jamming
Granular media jam into a panoply of metastable states. The way in which
these states are achieved depends on the nature of local and global constraints
on grains; here we investigate this issue by means of a non-equilibrium
stochastic model of a hindered granular column near its jamming limit. Grains
feel the constraints of grains above and below them differently, depending on
their position. A rich phase diagram with four dynamical phases (ballistic,
activated, logarithmic and glassy) is revealed. The statistics of the jamming
time and of the metastable states reached as attractors of the zero-temperature
dynamics is investigated in each of these phases. Of particular interest is the
glassy phase, where intermittency and a strong deviation from Edwards' flatness
are manifest.Comment: 23 pages, 12 figure
Comment on ``Relativistic cluster dynamics of nucleons and mesons. II. Formalism and examples''
In a recent paper [Phys.\ Rev.\ C{\bf 49}, 2142 (1994)], Haberzettl presented
cluster N-body equations for arbitrarily large systems of nucleons and mesons.
Application to the three-nucleon system is claimed to yield a new kind of
three-nucleon force. We demonstrate that these three-nucleon equations contain
double counting.Comment: 6 pages in Revtex 3.0, 6 Postscript figures. Accepted for publication
in Phys. Rev.
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