5,323 research outputs found
Nuclear Physics from lattice QCD at strong coupling
We study numerically the strong coupling limit of lattice QCD with one flavor
of massless staggered quarks. We determine the complete phase diagram as a
function of temperature and chemical potential, including a tricritical point.
We clarify the nature of the low temperature dense phase, which is strongly
bound nuclear matter. This strong binding is explained by the nuclear
potential, which we measure. Finally, we determine, from this first-principle
limiting case of QCD, the masses of atomic nuclei up to A=12 "carbon".Comment: 4 pages, 5 figures; v2: references added, minor changes, published
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Extended Iterative Scheme for QCD: Three-point Vertices
In the framework of a generalized iterative scheme introduced previously to
account for the non-analytic coupling dependence associated with the
renormalization-group invariant mass scale Lambda, we establish the
self-consistency equations of the extended Feynman rules (Lambda-modified
vertices of zeroth perturbative order) for the three-gluon vertex, the two
ghost vertices, and the two vertices of massless quarks. Calculations are
performed to one-loop-order, in Landau gauge, and at the lowest approximation
level (r=1) of interest for QCD. We discuss the phenomenon of compensating
poles inherent in these equations, by which the formalism automatically cancels
unphysical poles on internal lines, and the role of composite-operator
information in the form of equation-of-motion condensate conditions. The
observed near decoupling of the four-gluon conditions permits a solution to the
2-and-3-point conditions within an effective one-parameter freedom. There
exists a parameter range in which one solution has all vertex coefficients
real, as required for a physical solution, and a narrower range in which the
transverse-gluon and massless-quark propagators both exhibit complex-conjugate
pole pairs.Comment: 28 pages, 7 figure
The ethical challenge of Touraine's 'living together'
In Can We Live Together? Alain Touraine combines a consummate analysis of crucial social tensions in contemporary societies with a strong normative appeal for a new emancipatory 'Subject' capable of overcoming the twin threats of atomisation or authoritarianism. He calls for a move from 'politics to ethics' and then from ethics back to politics to enable the new Subject to make a reality out of the goals of democracy and solidarity. However, he has little to say about the nature of such an ethics. This article argues that this lacuna could usefully be filled by adopting a form of radical humanism found in the work of Erich Fromm. It defies convention in the social sciences by operating from an explicit view of the 'is' and the 'ought' of common human nature, specifying reason, love and productive work as the qualities to be realised if we are to move closer to human solidarity. Although there remain significant philosophical and political differences between the two positions, particularly on the role to be played by 'the nation', their juxtaposition opens new lines of inquiry in the field of cosmopolitan ethics
Improved AdS/QCD Model with Matter
We study an improved AdS/QCD model at finite temperature and chemical
potential. An Ansatz for the beta-function for the boundary theory allows for
the derivation of a charged dilatonic black hole in bulk. The solution is
asymptotically RN-AdS in the UV and AdS2 * R3 in the IR. We discuss the
thermodynamical aspects of the solution. The fermionic susceptibilities are
shown to deviate from the free fermionic limits at asymptotic temperatures
despite the asymptotically free nature of the gauge coupling at the boundary.
The Polyakov line, the temporal and spatial string tensions dependence on both
temperature and chemical potential are also discussed
Satellite versus ground-based estimates of burned area: a comparison between MODIS based burned area and fire agency reports over North America in 2007
North American wildfire management teams routinely assess burned area on site during firefighting campaigns; meanwhile, satellite observations provide systematic and global burned-area data. Here we compare satellite and ground-based daily burned area for wildfire events for selected large fires across North America in 2007 on daily timescales. In a sample of 26 fires across North America, we found the Global Fire Emissions Database Version 4 (GFED4) estimated about 80% of the burned area logged in ground-based Incident Status Summary (ICS-209) over 8-day analysis windows. Linear regression analysis found a slope between GFED and ICS-209 of 0.67 (with R = 0.96). The agreement between these data sets was found to degrade at short timescales (from R = 0.81 for 4-day to R = 0.55 for 2-day). Furthermore, during large burning days (> 3000 ha) GFED4 typically estimates half of the burned area logged in the ICS-209 estimates
Getting Hooked on Supramolecular Coordination Chemistry
The author describes the beginnings of her research in Switzerland, the inspiration she received from her senior colleagues as well as her first successful research results in the chemistry of alkaline earth metal aggregates and silver coordination polymer networks. Her current interest
lies in the design of smart materials, using different building blocks from previous projects. These projects evolved in Geneva, Karlsruhe, Basel, and Fribourg, where she became a full professor in 2006
Eastern Airlines v. Floyd: Airline Passengers Denied Recovery for Emotional Distress Under The Warsaw Convention
This Note reviews prior district court and appellate court decisions regarding the translation and scope of bodily injury. Next, the Note discusses the Court\u27s analysis in Floyd, including the arguments for and against allowing recovery for emotional distress under the Warsaw Convention. Finally, the Note examines the ramifications of the Floyd Court\u27s interpretation and the uncertainties which remain in this area of the law
Jansen, F./Streit, U. (1992): Eltern als Therapeuten. Ein Leitfaden zum Umgang mit Schul- und Lernproblemen. Berlin: Springer (216 Seiten; DM 48,-) [Rezension]
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