Mural jako atrakcja turystyczna w mieście poprzemysłowym – przykład Łodzi

W artykule zaprezentowano rozwój łódzkich murali w XXI w., przedstawiono opinie uczestników wycieczek organizowanych w 2014 r. przez Galerię Urban Forms, której głównym zadaniem jest nasycenie tkanki miejskiej sztuką uliczną oraz jej promocja. Ponadto wskazano zasięg oddziaływania łódzkich murali poprzez analizę: wspomnień zarejestrowanych i udostępnionych na YouTube, informacji w mediach lokalnych, krajowych i zagranicznych, opinii udostępnionych w Internecie na blogach i w galeriach turystów oraz miłośników sztuki ulicznej, a także prezentacji w galeriach na stronach internetowych autorów murali. Pozwoliło to na poszukiwanie odpowiedzi na pytanie: czy murale mogą być atrakcją turystyczną miasta poprzemysłowego, jakim jest Łódź

Knowledge-to-fact arguments can deliver knowledge

In a recent paper, Murali Ramachandran endorses a principle that he thinks can help us solve the surprise test puzzle and cause problems for a Williamsonian argument against KK principles. But in this paper I argue that his principle is false and as a result it cannot do either

The Globular Cluster System in the Inner Region of the Giant Elliptical Galaxy NGC 4472

We present a study of globular clusters in the inner region of the giant elliptical galaxy NGC 4472, based on the HST WFPC2 archive data. We have found about 1560 globular cluster candidates at the galactocentric radius r < 4 arcmin. V-(V-I) diagram of these objects shows a dominant vertical structure which consists obviously of two components: blue globular clusters (BGCs) and red globular clusters (RGCs). The luminosity function of the globular clusters is derived to have a peak at V(max)=23.50+/-0.16 from Gaussian fitting. The distance to NGC 4472 is estimated to be d=14.7+/-1.3 Mpc.The peak luminosity for the RGCs is similar to that for the BGCs, which indicates that the RGCs may be several Gyrs younger than the BGCs. The mean luminosity of the bright BGCs decreases by 0.2 mag with increasing galactocentric radius over the range of 9 arcmin, while that of the RGCs does not. The observed color distribution of these globular clusters is distinctively bimodal with peaks at (V-I) = 0.98 and 1.23. The mean observed color of all the globular clusters with V < 23.9 mag is derived to be (V-I)=1.11. These colors are exactly the same as those for the globular clusters in M87. It is found that the relative number of the BGCs to the RGCs is increasing with the increasing galactocentric radius. Surface number density profiles of both the BGCs and RGCs get flat in the central region, and the core radii of the globular cluster systems are measured to be r_c = 1.9 arcmin for the BGCs, r_c = 1.2 arcmin for the RGCs, and r_c = 1.3 arcmin for the total sample, which are much larger than the stellar core of the galaxy. In general the properties of the globular clusters in the inner region of NGC 4472 are consistent with those of the globular clusters in the outer region of NGC 4472.Comment: 27 pages (AASLaTex), 22 Postscript Figures, Accepted for Publication in the Astronomical Journal, Jul. 31st, 200

On the Self-Consistent Response of Stellar Systems to Gravitational Shocks

We study the reaction of a globular star cluster to a time-varying tidal perturbation (gravitational shock) using self-consistent N-body simulations and address two questions. First, to what extent is the cluster interior protected by adiabatic invariants. Second, how much further energy change does the postshock evolution of the cluster potential produce and how much does it affect the dispersion of stellar energies. We introduce the adiabatic correction} as ratio of the energy change, , to its value in the impulse approximation. When the potential is kept fixed, the numerical results for the adiabatic correction for stars with orbital frequency \omega can be approximated as (1 + \omega^2 \tau^2)^{-\gamma}. For shocks with the characteristic duration of the order the half-mass dynamical time of the cluster, \tau < t_{dyn,h}, the exponent \gamma = 5/2. For more prolonged shocks, \tau > 4 t_{dyn,h}, the adiabatic correction is shallower, \gamma = 3/2. When we allow for self-gravity and potential oscillations which follow the shock, the energy of stars in the core changes significantly, while the total energy of the system is conserved. Paradoxically, the postshock potential fluctuations reduce the total amount of energy dispersion, . The effect is small but real and is due to the postshock energy change being statistically anti-correlated with the shock induced heating. These results are to be applied to Fokker-Planck models of the evolution of globular clusters.Comment: 20 pages; ApJ 513 (in press

Gli affreschi della cripta di Aquileia

Analisi iconografica e stilistica, con proposta di datazione legata anche alla committenza patriarcale, del ciclo di pitture murali del XII secolo nella cripta della basilica di Aquilei

Transmission and amplification of disturbances by massive halos

We study how massive halos respond to perturbations. Through numerical solution of the coupled linearized Boltzmann-Poisson equations, we find that halos transmit and amplify disturbances over large distances within galaxies. In particular, as Weinberg has noted, the halo provides an excellent medium for transmitting disturbances from the outer regions of galaxies to the inner regions. The dipolar response typically dominates and, in some cases, is very weakly damped. The monopole and quadrupole response can also make significant contributions. Overall, the results support the notion that disk structure can be excited by transmission of noise from the distant halo. The strong dipolar response suggests that halos play a role in producing lopsided disks. These results also suggest that, during formation from initial collapse, halos do not settle rapidly into static equilibrium: instead, they may continue to ring and interact with other embryonic components of the proto-galaxyComment: 22 pages, submitted to Ap