10,616 research outputs found
Civil Procedure as a Critical Discussion
This Article develops a model for analyzing legal dispute resolution systems as systems for argumentation. Our model meshes two theories of argument conceived centuries apart: contemporary argumentation theory and classical stasis theory. In this Article, we apply the model to the Federal Rules of Civil Procedure as a proof of concept. Specifically, the model analyzes how the Federal Rules of Civil Procedure function as a staged argumentative critical discussion designed to permit judge and jury to rationally resolve litigants’ differences in a reasonable manner. At a high level, this critical discussion has three phases: a confrontation, an (extended) opening, and a concluding phase. Those phases are the umbrella under which discrete argumentation phases occur at points we call stases. Whenever litigants seek a ruling or judgment, they reach a stasis—a stopping or standing point for arguing procedural points of disagreement. During these stases, the parties make arguments that fall into predictable “commonplace” argument types. Taken together, these stock argument types form a taxonomy of arguments for all civil cases. Our claim that the Federal Rules of Civil Procedure function as a system for argumentation is novel, as is our claim that civil cases breed a taxonomy of argument types. These claims also mark the beginning of a broader project. Starting here with the Federal Rules of Civil Procedure, we embark on a journey that we expect to follow for several years (and which we hope other scholars will join), exploring our model’s application across dispute resolution systems and using it to make normative claims about those systems. From a birds-eye view, this Article also represents a short modern trek in a much longer journey begun by advocates in city states in and near Greece nearly 2500 years ago
Suprathermal electron isotropy in high-beta solar wind and its role in heat flux dropouts
[1] Time variations in plasma beta and a parameter which measures isotropy in suprathermal electron pitch angle distributions show a remarkably close correspondence throughout the solar wind. The finding implies that high-beta plasma, with its multiple magnetic holes and sharp field and plasma gradients, is conducive to electron pitch-angle scattering, which reduces heat flux from the Sun without field-line disconnection. Thus the finding impacts our understanding of signatures we use to determine magnetic topology in the heliosphere
Star Formation in Dwarf Galaxies
We explore mechanisms for the regulation of star formation in dwarf galaxies.
We concentrate primarily on a sample in the Virgo cluster, which has HI and
blue total photometry, for which we collected H data at the Wise
Observatory. We find that dwarf galaxies do not show the tight correlation of
the surface brightness of H (a star formation indicator) with the HI
surface density, or with the ratio of this density to a dynamical timescale, as
found for large disk or starburst galaxies. On the other hand, we find the
strongest correlation to be with the average blue surface brightness,
indicating the presence of a mechanism regulating the star formation by the
older (up to 1 Gyr) stellar population if present, or by the stellar population
already formed in the present burst.Comment: 15 pages (LATEX aasms4 style) and three postscript figures, accepted
for publication in the Astrophysical Journa
A Dynamical Study of the Non-Star Forming Translucent Molecular Cloud MBM16: Evidence for Shear Driven Turbulence in the Interstellar Medium
We present the results of a velocity correlation study of the high latitude
cloud MBM16 using a fully sampled CO map, supplemented by new CO
data. We find a correlation length of 0.4 pc. This is similar in size to the
formaldehyde clumps described in our previous study. We associate this
correlated motion with coherent structures within the turbulent flow. Such
structures are generated by free shear flows. Their presence in this non-star
forming cloud indicates that kinetic energy is being supplied to the internal
turbulence by an external shear flow. Such large scale driving over long times
is a possible solution to the dissipation problem for molecular cloud
turbulence.Comment: Uses AAS aasms4.sty macros. Accepted for publication in Ap
Turbulent Cooling Flows in Molecular Clouds
We propose that inward, subsonic flows arise from the local dissipation of
turbulent motions in molecular clouds. Such "turbulent cooling flows" may
account for recent observations of spatially extended inward motions towards
dense cores. These pressure-driven flows may arise from various types of
turbulence and dissipation mechanisms. For the example of MHD waves and
turbulence damped by ion-neutral friction, sustained cooling flow requires that
the outer gas be sufficiently turbulent, that the inner gas have marginal
field-neutral coupling, and that this coupling decrease sufficiently rapidly
with increasing density. These conditions are most likely met at the transition
between outer regions ionized primarily by UV photons and inner regions ionized
primarily by cosmic rays. If so, turbulent cooling flows can help form dense
cores, with speeds faster than expected for ambipolar diffusion. Such motions
could reduce the time needed for dense core formation and could precede and
enhance the motions of star-forming gravitational infall.Comment: To appear ApJL, Nov.10, 4 ApJ style pages, Postscrip
Top-down Automated Theorem Proving (Notes for Sir Timothy)
We describe a "top down" approach for automated theorem proving (ATP).
Researchers might usefully investigate the forms of the theorems mathematicians
use in practice, carefully examine how they differ and are proved in practice,
and code all relevant domain concepts. These concepts encode a large portion of
the knowledge in any domain. Furthermore, researchers should write programs
that produce proofs of the kind that human mathematicians write (and publish);
this means proofs that might sometimes have mistakes; and this means making
inferences that are sometimes invalid.
This approach is meant to contrast with the historically dominant "bottom up"
approach: coding fundamental types (typically sets), axioms and rules for
(valid) inference, and building up from this foundation to the theorems of
mathematical practice and to their outstanding questions. It is an important
fact that the actual proofs that mathematicians publish in math journals do not
look like the formalized proofs of Russell & Whitehead's Principia Mathematica
(or modern computer systems like Lean that automate some of this
formalization). We believe some "lack of rigor" (in mathematical practice) is
human-like, and can and should be leveraged for ATP.Comment: Cross list with cs.A
Heliospheric plasma sheets
[1] As a high-beta feature on scales of hours or less, the heliospheric plasma sheet (HPS) encasing the heliospheric current sheet shows a high degree of variability. A study of 52 sector boundaries identified in electron pitch angle spectrograms in Wind data from 1995 reveals that only half concur with both high-beta plasma and current sheets, as required for an HPS. The remaining half lack either a plasma sheet or current sheet or both. A complementary study of 37 high-beta events reveals that only 5 contain sector boundaries while nearly all (34) contain local magnetic field reversals, however brief. We conclude that high-beta plasma sheets surround current sheets but that most of these current sheets are associated with fields turned back on themselves. The findings are consistent with the hypothesis that high-beta plasma sheets, both at and away from sector boundaries, are the heliospheric counterparts of the small coronal transients observed at the tips of helmet streamers, in which case the proposed mechanism for their release, interchange reconnection, could be responsible for the field inversions
Relativistic nucleon optical potentials with isospin dependence in Dirac Brueckner Hartree-Fock approach
The relativistic optical model potential (OMP) for nucleon-nucleus scattering
is investigated in the framework of Dirac-Brueckner-Hartree-Fock (DBHF)
approach using the Bonn-B One-Boson- Exchange potential for the bare
nucleon-nucleon interaction. Both real and imaginary parts of isospin-dependent
nucleon self-energies in nuclear medium are derived from the DBHF approach
based on the projection techniques within the subtracted T -matrix
representation. The Dirac potentials as well as the corresponding Schrodinger
equivalent potentials are evaluated. An improved local density approximation is
employed in this analysis, where a range parameter is included to account for a
finite-range correction of the nucleon-nucleon interaction. As an example the
total cross sections, differential elastic scattering cross sections, analyzing
powers for n, p + 27Al at incident energy 100 keV < E < 250 MeV are calculated.
The results derived from this microscopic approach of the OMP are compared to
the experimental data, as well as the results obtained with a phenomenological
OMP. A good agreement between the theoretical results and the measurements can
be achieved for all incident energies using a constant value for the range
parameter.Comment: 10 pages, 16 figure
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