Espais incorporats, llocs identitaris : Recorreguts per A cidade sitiada, de Clarice Lispector

Quin paper té la identitat a l’hora d’interpretar el lloc, entès com a espai viscut –incorporat–? Què fa que a un espai se li puguin inscriure significats i sentits de lloc? A través de quins mecanismes la ciutat –com a una possible materialització del lloc– permet que no tot els seus espais puguin ser incorporats per a tothom? Com podran tenir lloc els cossos que la norma mantè al marge? Les temptatives de resposta a aquestes preguntes tracen uns recorreguts que, a través de la lectura d’A cidade sitiada, de Clarice Lispector, n’obren d’altres entorn de la identitat, el lloc i el cos: tres conceptes que, conjugats, reinterpreten el sentit de pertinença identitària.

Leaving the Dark ages with AMIGA

We present an Analytic Model of Intergalactic-medium and GAlaxy (AMIGA) evolution since the dark ages. AMIGA is in the spirit of the popular semi-analytic models of galaxy formation, although it does not use halo merger trees but interpolates halo properties in grids that are progressively built. This strategy is less memory-demanding and allows one to start modeling at sufficiently high redshifts and low halo masses to have trivial boundary conditions. The number of free parameters is minimized by making a causal connection between physical processes usually treated as independent of each other, which leads to more reliable predictions. However, the strongest points of AMIGA are the following: (1) the inclusion of molecular cooling and metal-poor, population III (Pop III) stars with the most dramatic feedback and (2) accurate follow up of the temperature and volume filling factor of neutral, singly ionized, and doubly ionized regions, taking into account the distinct halo mass functions in those environments. We find the following general results. Massive Pop III stars determine the intergalactic medium metallicity and temperature, and the growth of spheroids and disks is self-regulated by that of massive black holes (MBHs) developed from the remnants of those stars. However, the properties of normal galaxies and active galactic nuclei appear to be quite insensitive to Pop III star properties due to the much higher yield of ordinary stars compared to Pop III stars and the dramatic growth of MBHs when normal galaxies begin to develop, which cause the memory loss of the initial conditions.