Nonequilibrium entropic bounds for Darwinian replicators

Life evolved on our planet by means of a combination of Darwinian selection and innovations leading to higher levels of complexity. The emergence and selection of replicating entities is a central problem in prebiotic evolution. Theoretical models have shown how populations of different types of replicating entities exclude or coexist with other classes of replicators. Models are typically kinetic, based on standard replicator equations. On the other hand, the presence of thermodynamical constrains for these systems remain an open question. This is largely due to the lack of a general theory of out of statistical methods for systems far from equilibrium. Nonetheless, a first approach to this problem has been put forward in a series of novel developements in non-equilibrium physics, under the rubric of the extended second law of thermodynamics. The work presented here is twofold: firstly, we review this theoretical framework and provide a brief description of the three fundamental replicator types in prebiotic evolution: parabolic, malthusian and hyperbolic. Finally, we employ these previously mentioned techinques to explore how replicators are constrained by thermodynamics.Comment: 12 Pages, 5 Figure

Which Communities should be afraid of Mobility? The Effects of Agglomeration Economies on the Sensitivity of Firm Location to Local Taxes

This paper examines the effects of agglomeration economies (AE) on the sensitivity of firm location to tax differentials. An initial reading of the story suggests that, with AE, when a firm moves into a community attracted by a tax reduction, other firms may decide to move in as well. This suggests that AE increase the sensitivity of firm location to local taxes. However, a second version of the story reads that, if economic activities are highly concentrated in space, AE might offset any tax differential, hence suggesting a reduction in this sensitivity. This paper provides a theoretical model of intraregional firm location with Marshallian AE that is able to generate both hypotheses: AE increase (decrease) the effect of taxes when locations are (are not) of a similar size. We then use Spanish municipal data for the period 1995-2002 to test these hypotheses, analyzing the combined effect of local business taxes and Marshallian AE on the intraregional location of employment. In line with the theory, a municipality with stronger AE experiences lower (higher) tax effects if it is sufficiently dissimilar (similar) to its neighbors in terms of size.local taxes, agglomeration economies, local employment growth, instrumental variables

Tax differentials and agglomeration economies in intraregional firm location

This paper analyses empirically how differences in local taxes affect the intraregional location of new manufacturing plants. These effects are examined within the random profit maximization framework while accounting for the presence of different types of agglomeration economies (localization/ urbanization/ Jacobs’ economies) at the municipal level. We look at the location decision of more than 10,000 establishments locating between 1996 and 2003 across more than 400 municipalities in Catalonia, a Spanish region. It is necessary to restrict the choice set to the local labor market and, above all, to control for agglomeration economies so as to identify the effects of taxes on the location of new establishments.Local taxes, Agglomeration economies, Firm location.

DimDim a l'aula

Resultat del grup de treball CIFE-GI "Incorporació de les TIC a la docència" essent un espai d'intercanvi d'experiències i de promoció de la transferència d'activitats docents dutes a terme amb el suport de les TIC.Seguiment de la classe mitjaçant DimDi

Proposta de millora paisatgística del passeig marítim de sitges en el tram comprès entre el restaurant kansas i la riera de ribes

Treball final de carreraEl tram on s’actua té una secció constant que compren: la vorera adjunta a les cases de primera línia de mar amb una alineació de vegetació diversa molt maltractada, una via per al trànsit rodat de dos sentits i amb places d’aparcament a ambdues bandes, el passeig per a vianants amb una alineació de palmeres amb arbustos intercalats i uns parterres de gespa d’amplada variable que s’estenen fins més enllà de la meitat del passeig. És un passeig amb una escala relacionada amb la seva longitud (2 Km), però en cap cas, pensada per a la persona. Aquesta conformació comporta un passeig monòton, lineal i calorós, molt diferent del tram precedent , el passeig històric, on tenen gran importància l’abundant vegetació i la topografia marcada que el caracteritza. Es proposa una reordenació i, en alguns casos, fragmentació dels parterres de gespa existents de tal manera que modifiquin el recorregut de la gent i que juntament amb la plantació d’espècies arbòries, arbustives i herbàcies, totes elles de baix manteniment, es generi un espai amè, fresc i que convidi a passejar-hi. També s’intervindrà deixant un únic sentit de circulació i s’eliminaran les places d’una banda per a crear un carril per al transport públic i descongestionar la circulació. No s’intervindrà excessivament en els paviments només prolongant l’existent en les zones on eliminarem els parterres. Tot això fa que la proposta no necessiti un gran pressupost i que sigui totalment assequible per a l’ajuntament