Observable implications of geometrical and dynamical aspects of freeze-out in heavy ion collisions

Using an analytical parameterization of hadronic freeze-out in relativistic heavy ion collisions, we present a detailed study of the connections between features of the freeze-out configuration and physical observables. We focus especially on anisotropic freeze-out configurations (expected in general for collisions at finite impact parameter), azimuthally-sensitive HBT interferometry, and final-state interactions between non-identical particles. Model calculations are compared with data taken in the first year of running at RHIC; while not perfect, good agreement is found, raising the hope that a consistent understanding of the full freeze-out scenario at RHIC is possible, an important first step towards understanding the physics of the system prior to freeze-out.Comment: 36 pages, 56 figures, 2 tables; version accepted for publication in PRC: some figures, references and discussion added; now also discusses classical versus quantum statistic

Non-Abelian vortices with a twist

Non-Abelian flux-tube (string) solutions carrying global currents are found in the bosonic sector of four-dimensional N = 2 super-symmetric gauge theories. The specific model considered here possesses U(2)local×SU(2)global symmetry, with two scalar dou- blets in the fundamental representation of SU(2). We construct string solutions that are stationary and translationally symmetric along the x3 direction, and they are character- ized by a matrix phase between the two doublets, referred to as “twist”. Consequently, twisted strings have nonzero (global) charge, momentum, and in some cases even angular momentum per unit length. The planar cross section of a twisted string corresponds to a rotationally symmetric, charged non-Abelian vortex, satisfying first order Bogomolny-type equations and second order Gauss-constraints. Interestingly, depending on the nature of the matrix phase, some of these solutions even break cylindrical symmetry in R3. Al- though twisted vortices have higher energy than the untwisted ones, they are expected to be linearly stable since one can maintain their charge (or twist) fixed with respect to small perturbations

Axistationary perfect fluids -- a tetrad approach

Stationary axisymmetric perfect fluid space-times are investigated using the curvature description of geometries. Attention is focused on space-times with a vanishing electric part of the Weyl tensor. It is shown that the only incompressible axistationary magnetic perfect fluid is the interior Schwarzschild solution. The existence of a rigidly rotating perfect fluid, generalizing the interior Schwarzschild metric is proven. Theorems are stated on Petrov types and electric/magnetic Weyl tensors.Comment: 12 page

Idylls of socialism : the Sarajevo Documentary School and the problem of the Bosnian sub-proletariat

This historical overview of the Sarajevo Documentary School considers the films, in the light of their recent re-emergence, as indicative of both the legacy of socialist realism (even in the context of Yugoslav media) and attempted social engineering in the Bosnia of the 1960s and 1970s. The argument is made that the documentaries, despite their questionable aesthetic status (in respect of cinma-vrit and ethnography) and problematic ideological strategies and attempted interventions, document a history and offer insights that counter the prevailing revisionist trends in the presentation of Eastern and Central European history

Thermal Hadron Production in High Energy Heavy Ion Collisions

We provide a method to test if hadrons produced in high energy heavy ion collisions were emitted at freeze-out from an equilibrium hadron gas. Our considerations are based on an ideal gas at fixed temperature $T_f$, baryon number density $n_B$, and vanishing total strangeness. The constituents of this gas are all hadron resonances up to a mass of 2 GeV; they are taken to decay according to the experimentally observed branching ratios. The ratios of the various resulting hadron production rates are tabulated as functions of $T_f$ and $n_B$. These tables can be used for the equilibration analysis of any heavy ion data; we illustrate this for some specific cases.Comment: 12 pages (not included :13 figures + tables) report CERN-TH 6523/92 and Bielefeld preprint BI-TP 92/0

A procedurális emlékezet szerepe a testkép zavaraiban = The role of procedural memory in trouble of body picture

Az evészavarok egyik vezető betegségfenntartó tényezője a betegek torzult, diszfunkcionális kogníciója. Ezen belül is kiemelendők a táplálékfelvételi viselkedés zavaraival és a testélménnyel kapcsolatban lévő, a zavarok létrejöttében kulcsszerepet játszó kognitív disztorziók, melyek az információfeldolgozási folyamatokon belül elsősorban a perceptuális élményfeldolgozást érintik és evészavaros betegeknél a testkép speciális zavarában mutatkoznak meg. A kognitív információfeldolgozást a sémák irányítják, amelyekben a selfről való komplex tudás szerveződik. A sémák procedurális ismeretanyagot is hordoznak, úgy mint motoros készségeket, szokásokat, szabályokat, célképzeteket, döntéshozatali stratégiákat. Ezek alapján felmerül, hogy az evészavarokra jellemző viselkedéses rutincselekvések, mint például a diétázás, falásroham, önhánytatás a testkép sémáján belül procedurális élményanyagként kódolódhat és a munkamemóriában automatikusan a többi explicit tudással és emlékkel együtt aktiválódik. Elméleti áttekintésünkben ezeknek a prekognitív folyamatoknak keressük a helyét és szerepét az evészavaros betegekre jellemző kognitív információfeldolgozási jellegzetességek kialakításában

On the order of summability of the Fourier inversion formula

In this article we show that the order of the point value, in the sense of Łojasiewicz, of a tempered distribution and the order of summability of the pointwise Fourier inversion formula are closely related. Assuming that the order of the point values and certain order of growth at infinity are given for a tempered distribution, we estimate the order of summability of the Fourier inversion formula. For Fourier series, and in other cases, it is shown that if the distribution has a distributional point value of order k, then its Fourier series is e.v. Cesàro summable to the distributional point value of order k+1. Conversely, we also show that if the pointwise Fourier inversion formula is e.v. Cesàro summable of order k, then the distribution is the (k+1)-th derivative of a locally integrable function, and the distribution has a distributional point value of order k+2. We also establish connections between orders of summability and local behavior for other Fourier inversion problems

Towards a critical theory of communication as renewal and update of Marxist humanism in the age of digital capitalism

This paper's task is to outline some foundations of a critical, Marxist-humanist theory of communication in the age of digital capitalism. It theorises the role of communication in society, communication and alienation, communication in social struggles, social struggles for democratic communication, the contradictions of digital capitalism, and struggles for digital socialist humanism. Marxist humanism is a counter-narrative, counter-theory, and counter-politics to neoliberalism, new authoritarianism, and postmodernism. A critical theory of communication can should draw on this intellectual tradition. Communication and work stand in a dialectical relationship. Communication mediates, organises and is the process of the production of sociality and therefore of the reproduction of society. Society and communication are in class and capitalist societies shaped by the antagonism between instrumental and co-operative reason. Authoritarianism and humanism are two basic, antagonistic modes of organisation of society and communication. Instrumental reason creates and universalises alienation. Digital capitalism is a dimension of contemporary society where digital technologies such as the computer, the Internet, the mobile phone, tablets, robots, and AI-driven (“smart”) technologies mediate the accumulation of capital, influence, and reputation. A Marxist-humanist theory of communication aims to inform struggles for a good, commons-based, public Internet in a good, commons-based society that has a vivid, democratic public sphere