Functional Urban Areas as the Focus of Development Policy in Poland

This article presents the premises, current status and the prospects of using functional urban areas as the focus of Poland's development policy. For the past 10 years, cities, especially large ones, have been increasingly impacting on their surrounding areas defined as functional urban areas. The size of those areas is determined by the process of suburbanisation. The article emphasises the issue of uncoordinated development of functional urban areas surrounding core cities and on grassroot and top-down attempts to integrate their development

Screening at finite temperature and density

We present lattice QCD results on heavy quark free energies, extract from its temperature dependence entropy and internal energy contributions, and discuss the onset of medium effects that lead to screening of static quark-antiquark sources in a thermal medium. Most results are obtained in (2+1)-flavour QCD on a line of constant physics with almost realistic quark masses and compared to previous results from 2-flavor QCD as well as pure gauge theory. Furthermore, we discuss results on the density dependence of screening masses that have been obtained using a leading order Taylor expansion in the baryon chemical potential.Comment: 10 pages, 15 figures, Presented at Critical Point and Onset of Deconfinement 4th International Workshop, GSI Darmstadt, Germany, July 9-13 200

Architecture of Poland as the Heritage of the Past in the Present. Castles, palaces and mansions, historic cities

The present book “Poland – History, Culture and Society. Selected Readings” is the third edition of a collection of academic texts written with the intention to accompany the module by providing incoming students with teaching materials that will assist them in their studies of the course module and encourage further search for relevant information and data. The papers collected in the book have been authored by academic teachers from the University of Łódź, specialists in such fields as history, geography, literature, sociology, ethnology, cultural studies, and political science. Each author presents one chapter related to a topic included in the module or extending its contents. The book contains the extensive bibliography

Abstract objects: Species, Kinds, Concepts

In the paper I present Kotarbiński’s approach to abstract objects and show some mistakes in his investigations. By formal ontology I try to explain Kotarbiński’s view and proffer a new solution, a formal solution that is – I hope – in the spirit of Lvov–Warsaw (Lwów–Warsaw) School

Continuum estimate of the heavy quark momentum diffusion coefficient κ\kappa

Among quantities playing a central role in the theoretical interpretation of heavy ion collision experiments at RHIC and LHC are so-called transport coefficients. Out of those heavy quark diffusion coefficients play an important role e.g. for the analysis of the quenching of jets containing c or b quarks (D or B mesons) as observed at RHIC and LHC. We report on a lattice investigation of heavy quark momentum diffusion within pure SU(3) plasma above the deconfinement transition with the quarks treated to leading order in the heavy mass expansion. We measure the relevant colour-electric Euclidean correlator and based on several lattice spacings perform the continuum extrapolation. This extends our previous studies progressing towards a removal of lattice artifacts and a physical interpretation of the results. We find that the correlation function clearly exceeds its perturbative counterpart which suggests that at temperatures just above the critical one, non-perturbative interactions felt by the heavy quarks are stronger than within the weak-coupling expansion. Using an Ansatz for the spectral function which includes NNLO perturbative contributions we were able to determine, for the first time, a continuum estimate for the heavy quark momentum diffusion coefficient.Comment: 4 pages, 4 figures, to appear in the proceedings of the 24th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (Quark Matter 2014), accepted version to appear in Nucl.Phys.

Heavy quark free energies for three quark systems at finite temperature

We study the free energy of static three quark systems in singlet, octet, decuplet and average color channels in the quenched approximation and in 2-flavor QCD at finite temperature. We show that in the high temperature phase singlet and decuplet free energies of three quark systems are well described by the sum of the free energies of three diquark systems plus self energy contributions of the three quarks. In the confining low temperature phase we find evidence for a Y-shaped flux tube in SU(3) pure gauge theory, which is less evident in 2-flavor QCD due to the onset of string breaking. We also compare the short distance behavior of octet and decuplet free energies to the free energies of single static quarks in the corresponding color representations.Comment: 11 pages, 17 figure

The Problem of Mass: Mesonic Bound States Above T_c

We discuss the problem of mass, noting that meson masses decrease with increasing scale as the dynamically generated condensate of "soft glue" is melted (Brown/Rho scaling). We then extend the Bielefeld LGS color singlet interaction computed for heavy quarks in a model-dependent way by including the Ampere law velocity-velocity interaction. Parameterizing the resulting interaction in terms of effective strength of the potential and including screening, we find that the masses of pi, sigma, rho and A1 excitations, 32 degrees of freedom in all, go to zero (in the chiral limit) as T goes to Tc essentially independently of the input quark (thermal) masses in the range of 1-2 GeV, calculated also in Bielefeld. We discuss other LGS which show q-bar q bound states, which we interpret as our chirally restored mesons, for T > Tc.Comment: 20 pages, 6 figures (Table 2 is added

Screening of heavy quark free energies at finite temperature and non-zero baryon chemical potential

We analyze the dependence of heavy quark free energies on the baryon chemical potential (mu_b) in 2-flavour QCD using improved (p4) staggered fermions with a bare quark mass of m/T = 0.4. By performing a 6th order Taylor expansion in the chemical potential which circumvents the sign problem. The Taylor expansion coefficients of colour singlet and colour averaged free energies are calculated and from this the expansion coefficients for the corresponding screening masses are determined. We find that for small mu_b the free energies of a static quark anti-quark pair decrease in a medium with a net excess of quarks and that screening is well described by a screening mass which increases with increasing mu_b. The mu_b-dependent corrections to the screening masses are well described by perturbation theory for T > 2 T_c. In particular, we find for all temperatures above T_c that the expansion coefficients for singlet and colour averaged screening masses differ by a factor 2.Comment: 14 page

Static quark anti-quark interactions in zero and finite temperature QCD. I. Heavy quark free energies, running coupling and quarkonium binding

We analyze heavy quark free energies in 2-flavor QCD at finite temperature and the corresponding heavy quark potential at zero temperature. Static quark anti-quark sources in color singlet, octet and color averaged channels are used to probe thermal modifications of the medium. The temperature dependence of the running coupling, $\alpha_{qq}(r,T)$, is analyzed at short and large distances and is compared to zero temperature as well as quenched calculations. In parts we also compare our results to recent findings in 3-flavor QCD. We find that the characteristic length scale below which the running coupling shows almost no temperature dependence is almost twice as large as the Debye screening radius. Our analysis supports recent findings which suggest that $\chi_c$ and $\psi\prime$ are suppressed already at the (pseudo-) critical temperature and thus give a probe for quark gluon plasma production in heavy ion collision experiments, while $J/\psi$ may survive the transition and will dissolve at higher temperatures.Comment: 16 pages, 15 encapsulated postscript figures, revtex