325 research outputs found
Human Ecology and Public Policy: Overcoming the Hegemony of Economics
The thinking of those with the power to formulate and implement public policy is now almost totally dominated by the so-called science of economics. While efforts have been made to supplement or modify economics to make it less brutal or less environmentally blind, here it is suggested that economics is so fundamentally flawed and that it so completely dominates the culture of late modern capitalism (or postmodernity) that a new master human science is required to displace it and provide an alternative coordinating framework for research and for defining reality. This could then provide an alternative basis for formulating public policy. It is argued that if human ecology is to fill this role, it will must be developed on consistently anti-reductionist foundations, and that such a social science would totally reorient public policy from a domain for power elites to a domain for genuinely democratic societies to define and control their destinies
Controllability of 2D Euler and Navier-Stokes equations by degenerate forcing
We study controllability issues for the 2D Euler and Navier-
Stokes (NS) systems under periodic boundary conditions. These systems
describe motion of homogeneous ideal or viscous incompressible fluid on
a two-dimensional torus T^2. We assume the system to be controlled by
a degenerate forcing applied to fixed number of modes.
In our previous work [3, 5, 4] we studied global controllability by
means of degenerate forcing for Navier-Stokes (NS) systems with nonvanishing
viscosity (\nu > 0). Methods of dfferential geometric/Lie algebraic
control theory have been used for that study. In [3] criteria for
global controllability of nite-dimensional Galerkin approximations of
2D and 3D NS systems have been established. It is almost immediate
to see that these criteria are also valid for the Galerkin approximations
of the Euler systems. In [5, 4] we established a much more intricate suf-
cient criteria for global controllability in finite-dimensional observed
component and for L2-approximate controllability for 2D NS system.
The justication of these criteria was based on a Lyapunov-Schmidt
reduction to a finite-dimensional system. Possibility of such a reduction
rested upon the dissipativity of NS system, and hence the previous
approach can not be adapted for Euler system.
In the present contribution we improve and extend the controllability
results in several aspects: 1) we obtain a stronger sufficient condition for
controllability of 2D NS system in an observed component and for L2-
approximate controllability; 2) we prove that these criteria are valid for
the case of ideal incompressible uid (\nu = 0); 3) we study solid controllability
in projection on any finite-dimensional subspace and establish a
sufficient criterion for such controllability
Defining biodiverse reforestation: Why it matters for climate change mitigation and biodiversity
Reforestation to capture and store atmospheric carbon is increasingly championed as a climate change mitigation policy response. Reforestation plantings have the potential to provide conservation co-benefits when diverse mixtures of native species are planted, and there are growing attempts to monetise biodiversity benefits from carbon reforestation projects, particularly within emerging carbon markets. But what is meant by ‘biodiverse’ across different stakeholders and groups implementing and overseeing these projects and how do these perceptions compare with long-standing scientific definitions? Here, we discuss approaches to, and definitions of, biodiversity in the context of reforestation for carbon sequestration. Our aim is to review how the concept of biodiversity is defined and applied among stakeholders (e.g., governments, carbon certifiers and farmers) and rights holders (i.e., First Nations people) engaging in reforestation, and to identify best-practice methods for restoring biodiversity in these projects. We find that some stakeholders have a vague understanding of diversity across varying levels of biological organisation (genes to ecosystems). While most understand that biodiversity underpins ecosystem functions and services, many stakeholders may not appreciate the difficulties of restoring biodiversity akin to reference ecosystems. Consequently, biodiversity goals are rarely explicit, and project goals may never be achieved because the levels of restored biodiversity are inadequate to support functional ecosystems and desired ecosystem services. We suggest there is significant value in integrating biodiversity objectives into reforestation projects and setting specific restoration goals with transparent reporting outcomes will pave the way for ensuring reforestation projects have meaningful outcomes for biodiversity, and legitimate incentive payments for biodiversity and natural capital accounting
The Seven-sphere and its Kac-Moody Algebra
We investigate the seven-sphere as a group-like manifold and its extension to
a Kac-Moody-like algebra. Covariance properties and tensorial composition of
spinors under are defined. The relation to Malcev algebras is
established. The consequences for octonionic projective spaces are examined.
Current algebras are formulated and their anomalies are derived, and shown to
be unique (even regarding numerical coefficients) up to redefinitions of the
currents. Nilpotency of the BRST operator is consistent with one particular
expression in the class of (field-dependent) anomalies. A Sugawara construction
is given.Comment: 22 pages. Macropackages used: phyzzx, epsf. Three epsf figure files
appende
Minimum Wages and Poverty with Income-Sharing
Textbook analysis tells us that in a competitive labor market, the introduction of a minimum wage in terms of poverty rather than in terms of unemployment. This paper makes three contributions to the basic theory of the minimum wage. First, we analyze the effects of a higher minimum wage in terms of poverty rather than in terms of unemployment. Second, we extend the standard textbook model to allow for income-sharing between employed and unemployed persons in society. Third, we extend the basic model to deal with income sharing within families. We find that there are situations in which a higher minimum wage raises poverty, others where it reduces poverty, and yet others in which poverty is unchanged. We characterize precisely how the poverty effect depends on four parameters: the degree of poverty aversion, the elasticity of labor demand, the ratio of the minimum wage to the poverty line, and the extent of income-sharing. Thus, shifting the perspective from unemployment to poverty leads to a considerable enrichment of the theory of the minimum wage
Quasi-particle model for lattice QCD: quark-gluon plasma in heavy ion collisions
We propose a quasi-particle model to describe the lattice QCD equation of
state for pure SU(3) gauge theory in its deconfined state, for .
The method involves mapping the interaction part of the equation of state to an
effective fugacity of otherwise non-interacting quasi-gluons. We find that this
mapping is exact. Using the quasi-gluon distribution function, we determine the
energy density and the modified dispersion relation for the single particle
energy, in which the trace anomaly is manifest. As an application, we first
determine the Debye mass, and then the important transport parameters, {\it
viz}, the shear viscosity, and the shear viscosity to entropy density
ratio, . We find that both and
are sensitive to the interactions, and that the interactions significantly
lower both and .Comment: 10 pages, 8 figures, epj class file, version accepted for publication
in Euro. Phys.J
Experimental and Theoretical Challenges in the Search for the Quark Gluon Plasma: The STAR Collaboration's Critical Assessment of the Evidence from RHIC Collisions
We review the most important experimental results from the first three years
of nucleus-nucleus collision studies at RHIC, with emphasis on results from the
STAR experiment, and we assess their interpretation and comparison to theory.
The theory-experiment comparison suggests that central Au+Au collisions at RHIC
produce dense, rapidly thermalizing matter characterized by: (1) initial energy
densities above the critical values predicted by lattice QCD for establishment
of a Quark-Gluon Plasma (QGP); (2) nearly ideal fluid flow, marked by
constituent interactions of very short mean free path, established most
probably at a stage preceding hadron formation; and (3) opacity to jets. Many
of the observations are consistent with models incorporating QGP formation in
the early collision stages, and have not found ready explanation in a hadronic
framework. However, the measurements themselves do not yet establish
unequivocal evidence for a transition to this new form of matter. The
theoretical treatment of the collision evolution, despite impressive successes,
invokes a suite of distinct models, degrees of freedom and assumptions of as
yet unknown quantitative consequence. We pose a set of important open
questions, and suggest additional measurements, at least some of which should
be addressed in order to establish a compelling basis to conclude definitively
that thermalized, deconfined quark-gluon matter has been produced at RHIC.Comment: 101 pages, 37 figures; revised version to Nucl. Phys.
Phi meson production in Au+Au and p+p collisions at sqrt (s)=200 GeV
We report the STAR measurement of Phi meson production in Au+Au and p+p
collisions at sqrt (s)=200 GeV. Using the event mixing technique, the Phi
spectra and yields are obtained at mid-rapidity for five centrality bins in
Au+Au collisions and for non-singly-diffractive p+p collisions. It is found
that the Phi transverse momentum distributions from Au+Au collisions are better
fitted with a single-exponential while the p+p spectrum is better described by
a double-exponential distribution. The measured nuclear modification factors
indicate that Phi production in central Au+Au collisions is suppressed relative
to peripheral collisions when scaled by the number of binary collisions. The
systematics of versus centrality and the constant Phi/K- ratio versus beam
species, centrality, and collision energy rule out kaon coalescence as the
dominant mechanism for Phi production.Comment: 6 pages, 3 figures, submitted to Phys. Rev. Let
Relevance of nucleon spin in amplitude analysis of reactions pi(-)p->pi(0)pi(0)n and pi(-)p->eta eta n
The measurements of reactions and on polarized targets at CERN found a strong dependence of pion
production amplitudes on nucleon spin. Analyses of recent measurements of
reaction on unpolarized targets by GAMS
Collaboration at 38 GeV/c and BNL E852 Collaboration at 18 GeV/c use the
assumption that pion production amplitudes do not depend on nucleon spin, in
conflict with the CERN results on polarized targets. We show that measurements
of and on unpolarized
targets can be analysed in a model independent way in terms of 4 partial-wave
intensities and 3 independent interference phases in the mass region where -
and -wave dominate. We also describe model-independent amplitude analysis of
reaction measured on polarized target, both in the
absence and in the presence of -wave amplitudes. We suggest that high
statistics measurements of reactions and be made on polarized targets at Protvino IHEP and at BNL, and
that model-independent amplitude analyses of this polarized data be performed
to advance hadron spectroscopy on the level of spin dependent production
amplitudes.Comment: 54 page
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