Deformed Wong Particles

By generalizing the Feynman proof of the Lorentz force law, recently reported by Dyson, we derive equations of motion for particles possessing internal degrees of freedom $I^a$ which do not, in general, generate a finite algebra. We obtain consistency criteria for fields which interact with such particles. It is argued that when a particle with internal $SU_q(2)$ degrees of freedom is coupled to $SU(2)$ gauge fields, $SU(2)$ gauge invariance is broken to $U(1)$. We further claim that when such an $SU_q(2)$ particle acts as a source for the field theory, the second rank antisymmetric field tensor, in general, cannot be globally defined.Comment: 14 pages, LATE

Two-parameter deformation of the Poincar\'e algebra

We examine a two-parameter ($\hbar ,$ $\lambda$) deformation of the Poincar\`e algebra which is covariant under the action of $SL_q(2,C).$ When $\lambda \rightarrow 0$ it yields the Poincar\`e algebra, while in the $\hbar\rightarrow 0$ limit we recover the classical quadratic algebra discussed previously in \cite{ssy95}, \cite{sy95}. The analogues of the Pauli-Lubanski vector $w$ and Casimirs $p^2$ and $w^2$ are found and a set of mutually commuting operators is constructed.Comment: 10 pages, Latex2

Deformation Quantization of the Isotropic Rotator

We perform a deformation quantization of the classical isotropic rigid rotator. The resulting quantum system is not invariant under the usual $SU(2)\times SU(2)$ chiral symmetry, but instead $SU_{q^{-1}}(2) \times SU_q(2)$.Comment: 12pp, LATE

The Other Pathway To The Boardroom: Interpersonal Influence Behavior As A Substitute For Elite Credentials And Majority Status In Obtaining Board Appointments

Using survey data on interpersonal influence behavior from a large sample of managers and chief executive officers (CEOs) at Forbes 500 companies, we examine how ingratiatory behavior directed at individuals who control access to board positions can provide an alternative pathway to the boardroom for managers who lack the social and educational credentials associated with the power elite. Findings show that top managers who engage in ingratiatory behavior toward their CEO, with ingratiation comprising flattery, opinion conformity, and favor-rendering, will be more likely to receive board appointments at other firms where their CEO serves as director and at boards to which the CEO is indirectly connected in the board interlock network. Further results suggest that interpersonal influence behavior substitutes to some degree for the advantages of an elite background or demographic majority status. Our findings help explain why norms of director deference to CEOs have persisted despite increased diversity in the corporate elite and have implications for research on corporate governance, social networks in the corporate elite, and for the sociological question of whether demographic minorities and individuals who lack privileged backgrounds have equal access to positions of leadership in large U.S. companies. Our study ultimately suggests that such individuals face a rather subtle and perhaps unexpected form of social discrimination, in that they must engage in a higher level of interpersonal influence behavior in order to have the same chance of obtaining a board appointment.Managemen

Global Sulfur Emissions in the 1990s

This paper provides global and individual country estimates of sulfur emissions from 1991-2000. Raw estimates are obtained in two ways. For countries and years with published data I compile that data from the available sources. For the remaining countries and for missing years for countries with some published data, I use either the decomposition model estimated by Stern (2002), the first differences environmental Kuznets curve model estimated by Stern and Common (2001), or a simple extrapolation, depending on the availability of data to interpolate or extrapolate estimates. The results are combined with estimates from the ASL database for earlier years to develop continuous time series from 1850 to 2000. Finally, I discuss the main movements in global and regional emissions in the 1990s and compare the results to other studies. Global emissions peaked in 1989 or 1991 and declined rapidly thereafter. The locus of emissions shifted towards East and South Asia, but even this region peaked in 1996. Our estimates tend to be lower than other published studies and show a much more rapid decline reflecting the view that technological progress in reducing sulfur based pollution has been rapid and is beginning to diffuse worldwide.

Reversal in the Trend of Global Anthropogenic Sulfur Emissions

Global anthropogenic sulfur emissions increased until the late 1980s. Existing estimates for 1995 and 2000 show a moderate decline from 1990 to 1995 or relative stability throughout the decade. This paper combines previously published data and new econometric estimates to show a 25% decline over the decade to a level not seen since the early 1960s. The decline is evident in North America, Western and Eastern Europe and in the last few years in East and South Asia. If this new trend is maintained local air pollution problems will be ameliorated but global warming may be somewhat exacerbated.

Derivation of the Hicks Elasticity of Substitution from the Input Distance Function

The Hicks or direct elasticity of substitution is traditionally derived from the production function. This paper exploits duality theory to present a more general derivation from the input distance function, which is exactly dual to the Shadow Elasticity of Substitution. The new elasticity is more general than the traditional one as it can handle situations of technical inefficiency, nonseparability between inputs and outputs, and multiple outputs, but is equal to the traditional elasticity under the classical conditions. The new derivation is related to the Morishima and Antonelli Elasticities of Complementarity in the same way that the Shadow Elasticity of Substitution is related to the Morishima and Allen-Uzawa Elasticities of Substitution. Furthermore, distance (technical efficiency) is not constant for the Morishima and Antonelli Elasticities of ComplementarityMicroeconomics; production; substitution

Global sulfur emissions in the 1990s

This paper provides global and country by country estimates of sulfur emissions for the early and mid-1990s. Raw estimates are obtained in two ways. For countries with published data we compile that data from the available sources. For the remaining countries, we use either the decomposition model estimated by Stern (1999), the first differences environmental Kuznets curve model estimated by Stern and Common (2001), or simple extrapolation depending on the availability of data on the explanatory variables. We then examine the compatibility of these estimates with the ASL estimates for 1990. Based on these and other comparisons we construct a preferred database for 1850-1999 and discuss the main movements in the 1990s. The data is available from the datasite.

The Physical Significance of Singularities in the Chern--Simons Fermi Liquid Description of a Partially Filled Landau Level

We analyze the linear response of a half filled Landau level to long wavelength and low frequency driving forces, using Fermi liquid theory for composite fermions. This response is determined by the composite fermions quasi--particle effective mass, $m^*$, and quasi--particle Landau interaction function $f(\theta-\theta')$. Analyzing infra--red divergences of perturbation theory, we get an exact expression for $m^*$, and conjecture the form of the $f(\theta-\theta')$. We then conclude that in the limit of infinite cyclotron frequency, and small ${\bf q},\omega$, the composite fermion excitation spectrum is continuous for $0<\omega<\gamma \frac{e^2}{\epsilon h}q$, with $\gamma$ an unknown number. For fractional quantum Hall states near a half filled Landau level, we derive an exact expression for the energy gap.Comment: 4 pages, RevTeX. This paper, being short and non-technical, could serve as a useful starting point for reading our manuscript cond-mat/9502032. The present paper does, however, include results not published in the forme