Complete Phase Diagrams for a Holographic Superconductor/Insulator System

The gravitational dual of an insulator/superconductor transition driven by increasing the chemical potential has recently been constructed. However, the system was studied in a probe limit and only a part of the phase diagram was obtained. We include the backreaction and construct the complete phase diagram for this system. For fixed chemical potential there are typically two phase transitions as the temperature is lowered. Surprisingly, for a certain range of parameters, the system first becomes a superconductor and then becomes an insulator as the temperature approaches zero. As a byproduct of our analysis, we also construct the gravitational dual of a Bose-Einstein condensate of glueballs in a confining gauge theory.Comment: 19 pages; v2: references adde

The Fiction Of Fishing: Richard Brautigan\u27s Metafictional Romance

The writings of Richard Brautigan achieved considerable popular and critical praise in the 1960s but were generally ignored or denounced thereafter. This dissertation offers a reassessment of Brautigan\u27s oeuvre by advancing a contemporary reading of his works within the critical and cultural environment of his times. After a preliminary examination of So the Wind Won\u27t Blow It All Away to illustrate the artful complexity of Brautigan\u27s final work, the dissertation examines the critical and literary framework that surrounded Brautigan\u27s earliest writings, submitting that his works are best understood in a postmodern critical context. Trout Fishing in America, A Confederate General from Big Sur, and In Watermelon Sugar are examined as metafictions, self-reflexive works that are concerned primarily with the nature of words and texts and which foreground the text itself as the dominant subject of fiction. In the 1970s, Brautigan turns this fully developed metafictional sensibility toward the genres of popular romance. Through a metafictional combination and adaptation of several romance forms, including western, gothic, erotic, detective and historical romance, these genre experimentations move Brautigan toward the development of a unique hybrid text that aspires to enfold all forms of human discourse in an elastic fictive structure--such is the final substance of Richard Brautigan\u27s metafictional romance

Holographic Josephson junctions.

We construct a gravitational dual of a Josephson junction. Calculations on the gravity side reproduce the standard relation between the current across the junction and the phase difference of the condensate. We also study the dependence of the maximum current on the temperature and size of the junction and reproduce familiar results

Influence of molecular weight average, degree of crystallinity, and viscosity of different polyamide PA12 powder grades on the microstructures of laser sintered part

Laser Sintering (LS) allows functional parts to be produced in a wide range of powdered materials using a dedicated machine, and is thus gaining popularity within the field of rapid prototyping. It offers the user the ability to optimise part design in order to meet customer requirements with few manufacturing restrictions. A problem with LS is that sometimes the surface of the parts produced displays a texture similar to that of the skin of an orange (the so-called “orange peel” texture). The main aim of this research is to develop a methodology of controlling the input material properties of PA12 powder that will ensure consistent and good quality of the fabricated parts. Melt Flow Rate (MFR) and Gel permeation chromatography (GPC) were employed to measure the flow viscosity and molecular weight distributions of Polyamide PA12 powder grades. The experimental results proved that recycle PA12 powder with higher melt viscosity polymer has a higher entanglement with a longer molecule chain causes a higher resistance to flow which cause poor and rough surface finished on laser sintered part

X-ray Over-Luminous Elliptical Galaxies: A New Class of Mass Concentrations in the Universe?

We detect four isolated, X-ray over-luminous (Lx>2e43 [h/0.5]**-2 erg/s) elliptical galaxies (OLEGs) in our 160 square degree ROSAT PSPC survey. The extent of their X-ray emission, total X-ray luminosity, total mass, and mass of the hot gas in these systems correspond to poor clusters, and the optical luminosity of the central galaxies (M_R<-22.5 + 5 lg h) is comparable to that of cluster cDs. However, there are no detectable fainter galaxy concentrations around the central elliptical. The mass-to-light ratio within the radius of detectable X-ray emission is in the range 250-450 Msun/Lsun, which is 2-3 times higher than typically found in clusters or groups. These objects can be the result of galaxy merging within a group. However, their high M/L values are difficult to explain in this scenario. OLEGs must have been undisturbed for a very long time, which makes them the ultimate examples of systmes in hydrostatic equilibrium. The number density of OLEGs is n=2.4(+3.1-1.2}x10**-7 (h/0.5)**-3 Mpc**-3 at the 90% confidence. They comprise 20% of all clusters and groups of comparable X-ray luminosity, and nearly all galaxies brighter than M_R=-22.5. The estimated contirubution of OLEGs to the total mass density in the Universe is close to that of T>7 keV clusters.Comment: 4 pages, 2 figures, uses emulateapj.sty, submitted to ApJ Letter