GOV-AARGH-NANCE – “EVEN CRIMINALS NEED LAW AND ORDER”

We present a theoretical model postulating that the relationship between crime and governance is “hump-shaped”, rather than linearly decreasing, when criminals need access to markets. State collapse, violent conflict and a lack of infrastructure are not conducive for the establishment of any business, legal or illegal. At the bottom end of the spectrum, therefore, criminal gangs benefit from improved governance, especially when this is delivered informally. With significant improvements in formal governance criminal activities decline. We use data from the International Maritime Bureau to create a new dataset on piracy and find strong and consistent support for this non-linear relationship.Governance; Crime; Piracy; Informal governance; Law enforcement

Gov-aargh-nance: "Even Criminals Need Law and Order"

We present a theoretical model postulating that the relationship between crime and governance is "hump-shaped" rather than linearly decreasing. State failure, anarchy and a lack of infrastructure are not conducive for the establishment of any business. This includes illegal businesses, as criminals need protection and markets to convert loot into consumables. At the bottom end of the spectrum, therefore, both legal business and criminal gangs benefit from improved governance, especially when this is delivered informally. With significant improvements in formal governance criminal activities decline. We use data from the International Maritime Bureau to create a new dataset on piracy and find strong and consistent support for this non-linear relationship. The occurrence, persistence and intensity of small-scale maritime crime are well approximated by a quadratic relationship with governance quality. Organised crime benefits from corrupt yet effective bureaucrats, and informally governed areas within countries.Governance, Crime, Piracy, Informal Institutions, Law enforcement

Gov-aargh-nance - "even criminals need law and order"

We present a theoretical model postulating that the relationship between crime and governance is "hump-shaped" rather than linearly decreasing. State failure, anarchy and a lack of infrastructure are not conducive for the establishment of any business. This includes illegal businesses, as criminals need protection and markets to convert loot into consumables. At the bottom end of the spectrum, therefore, both legal business and criminal gangs benefit from improved governance, especially when this is delivered informally. With significant improvements in formal governance criminal activities decline. We use data from the International Maritime Bureau to create a new dataset on piracy and find strong and consistent support for this non-linear relationship. The occurrence, persistence and intensity of small-scale maritime crime are well approximated by a quadratic relationship with governance quality. Organised crime benefits from corrupt yet effective bureaucrats, and informally governed areas within countries.

Relativistic Nucleus-Nucleus Collisions: Zone of Reactions and Space-Time Structure of a Fireball

A zone of reactions is determined and then exploited as a tool in studying the space-time structure of an interacting system formed in a collision of relativistic nuclei. The time dependence of the reaction rates integrated over spatial coordinates is also considered. Evaluations are made with the help of the microscopic transport model UrQMD. The relation of the boundaries of different zones of reactions and the hypersurfaces of sharp chemical and kinetic freeze-outs is discussed.Comment: 6 pages, 5 figure

Magneto-resistance in a lithography defined single constrained domain wall spin valve

We have measured domain wall magnetoresistance in a single lithographically constrained domain wall. An H-shaped Ni nano-bridge was fabricated by e-beam lithography with the two sides being single magnetic do- mains showing independent magnetic switching. The connection between the sides constraining the domain wall when the sides line up anti-parallel. The magneto-resistance curve clearly identifies the magnetic con- figurations that are expected from a spin valve-like structure. The value of the magneto-resistance at room temperature is around 0.1% or 0.4 ­. This value is shown to be in agreement with a theoretical formulation based on spin accumulation. Micromagnetic simulations show it is possible to reduce the size of the domain wall further by shortening the length of the bridge

Dielectric properties of charge ordered LuFe2O4 revisited: The apparent influence of contacts

We show results of broadband dielectric measurements on the charge ordered, proposed to be mul- tiferroic material LuFe2O4. The temperature and frequency dependence of the complex permittivity as investigated for temperatures above and below the charge-oder transition near T_CO ~ 320 K and for frequencies up to 1 GHz can be well described by a standard equivalent-circuit model considering Maxwell-Wagner-type contacts and hopping induced AC-conductivity. No pronounced contribution of intrinsic dipolar polarization could be found and thus the ferroelectric character of the charge order in LuFe2O4 has to be questioned.Comment: 4 pages, 3 figure

Dissipative hydrodynamics in 2+1 dimension

In 2+1 dimension, we have simulated the hydrodynamic evolution of QGP fluid with dissipation due to shear viscosity. Comparison of evolution of ideal and viscous fluid, both initialised under the same conditions e.g. same equilibration time, energy density and velocity profile, reveal that the dissipative fluid evolves slowly, cooling at a slower rate. Cooling get still slower for higher viscosity. The fluid velocities on the otherhand evolve faster in a dissipative fluid than in an ideal fluid. The transverse expansion is also enhanced in dissipative evolution. For the same decoupling temperature, freeze-out surface for a dissipative fluid is more extended than an ideal fluid. Dissipation produces entropy as a result of which particle production is increased. Particle production is increased due to (i) extension of the freeze-out surface and (ii) change of the equilibrium distribution function to a non-equilibrium one, the last effect being prominent at large transverse momentum. Compared to ideal fluid, transverse momentum distribution of pion production is considerably enhanced. Enhancement is more at high $p_T$ than at low $p_T$. Pion production also increases with viscosity, larger the viscosity, more is the pion production. Dissipation also modifies the elliptic flow. Elliptic flow is reduced in viscous dynamics. Also, contrary to ideal dynamics where elliptic flow continues to increase with transverse momentum, in viscous dynamics, elliptic flow tends to saturate at large transverse momentum. The analysis suggest that initial conditions of the hot, dense matter produced in Au+Au collisions at RHIC, as extracted from ideal fluid analysis can be changed significantly if the QGP fluid is viscous.Comment: 11 pages, 10 figures (revised). In the revised version, calculations are redone with ADS/CFT and perurbative estimate of viscosity. Comments on the unphysical effects like early reheating of the fluid, in 1st order dissipative theories are added. The particle spectra calculations are redone with modified programm

Hard thermal loops with a background plasma velocity

I consider the calculation of the two and three-point functions for QED at finite temperature in the presence of a background plasma velocity. The final expressions are consistent with Lorentz invariance, gauge invariance and current conservation, pointing to a straightforward generalization of the hard thermal loop formalism to this physical situation. I also give the resulting expression for the effective action and identify the various terms.Comment: 11 pages, no figure