La economía mexicana, 1830-1940: Obstáculos a la industrialización (I)

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La economía mexicana. 1810-1940: obstáculos a la industrialización (II)

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Concentración industrial, desarrollo del mercado de capitales y redes financieras basadas en el parentesco: un estudio comparado de Brasil, México y los Estados Unidos, 1840-1930 (2.ª parte)

Editada en la Universidad Carlos IIIEste artículo aborda la relación entre el desarrollo del mercado de capital y la estructura industrial durante las primeras etapas de la industrialización a partir de las experiencias de Brasil, México y los Estados Unidos. En él se arguye que las dos restricciones básicas a la formación de intermediarios crediticios en América Latina, una mala definición de derechos de propiedad y la intervención estatal, produjeron una concentración más alta en el textil algodonero de México y Brasil que en el de Estados Unidos.This article examines the relatíonship between capital market development and industrial structure during the early stages of industrialization, contrasting the experiences of Brazil, México, and the United States. It argues that the two constraints placed on the formation of credit intermediaries in Latin America, namely, poorly defined property rights and govemment regulatory policies, produced greater concentration in the Mexican and Braxilian cotton textile industries than that which developed in the United Stares.Publicad

On the Importance to Economic Success of Property Rights in Finance and Innovation

This Essay surveys recent developments across the fields of finance and innovation to highlight some common themes concerning the importance of property rights to economic success. Society regularly makes choices when shaping the precise contours of the legal institutions that govern the behavior of market actors, often in response to high profile issues like the collapse of Enron and the patenting of life-saving AIDS drugs. Recognizing that no set of legal institutions or related enforcement mechanisms will be perfect, this Essay explores some particularly helpful institutional features based on property rights that too often are overlooked by policy makers and commentators, even though these property-based institutional features have long been associated with economic success in a number of diverse settings

Low energy supersymmetry with a neutralino LSP and the CDF ee\gamma\gamma + missing E_T event

We present a refined and expanded analysis of the CDF ee\gamma\gamma + \Et event as superpartner production, assuming the lightest neutralino is the lightest supersymmetric particle. A general low-energy Lagrangian is constrained by a minimum cross section times branching ratio into two electrons and two photons, kinematics consistent with the event, and LEP1-LEP130 data. We examine how the supersymmetric parameters depend on the kinematics, branching ratios and experimental predictions with a selectron interpretation of the event, and discuss to what extent these are modified by other interpretations. Predictions for imminent CERN LEP upgrades and the present and future Fermilab Tevatron are presented. Finally, we briefly discuss the possible connection to other phenomena including a light stop, the neutralino relic density, the shift in $R_b$ and the associated shift in $\alpha_s$, and implications for the form of the theory.Comment: 57 pages, LaTeX, uses epsf.sty, 19 figures. Version accepted for publication in Phys. Rev. D, with minor changes and a few clarification

Supersymmetric analysis and predictions based on the CDF ee\gamma\gamma + missing E_T event

We have analyzed the single \eegg + \slashchar{E}_T event at CDF and found that the expected rate and kinematics are consistent with selectron pair production. We consider two classes of general low-energy supersymmetric theories, where either the lightest neutralino (``neutralino LSP'' scenario) or the gravitino (``light gravitino'' scenario) is the lightest supersymmetric particle. The parameter space of the supersymmetric Lagrangian is tightly constrained by the kinematics of the event and the branching ratios for the necessary decay chain of the selectron. We identify a region of the parameter space satisfying all low-energy constraints, and consistent with the selectron interpretation of the ee\gamma\gamma + \Et event. We discuss other supersymmetric processes at Fermilab Tevatron and at CERN LEP in both scenarios that could confirm or exclude a supersymmetric explanation of the event, and that could distinguish between the neutralino LSP and the light gravitino scenarios.Comment: 17 pages, LaTeX, uses epsf.sty, 4 encapsulated Postscript figures. Improved referencing. Minor changes in text and numbers, no qualitative changes in result

Raising the unification scale in supersymmetry

In the minimal supersymmetric standard model, the three gauge couplings appear to unify at a mass scale near $2 \times 10^{16}$ GeV. We investigate the possibility that intermediate scale particle thresholds modify the running couplings so as to increase the unification scale. By requiring consistency of this scenario, we derive some constraints on the particle content and locations of the intermediate thresholds. There are remarkably few acceptable solutions with a single cleanly defined intermediate scale far below the unification scale.Comment: 22 pages, macros included. One figure, available at ftp://ftp.phys.ufl.edu/incoming/rais.ep

Detecting a light Higgs boson at the Fermilab Tevatron through enhanced decays to photon pairs

We analyze the prospects of the Tevatron for finding a Higgs boson in the two photon decay mode. We conclude that the Standard Model (SM) Higgs boson will likely not be discovered in this mode. However, we motivate several theories beyond the SM, including the MSSM, that predict a Higgs boson with enhanced branching fractions into photons, and calculate the luminosity needed to discover a general Higgs boson at the Tevatron by a two-photon invariant mass peak at large transverse momentum. We find that a high luminosity Tevatron will play a significant role in discovering or constraining these theories.Comment: 20 pages, latex, 5 figure

Sparticle Spectrum Constraints

The supersymmetric standard model with supergravity-inspired soft breaking terms predicts a rich pectrum of sparticles to be discovered at the SSC, LHC and NLC. Because there are more supersymmetric particles than unknown parameters, one can write down sum rules relating their masses. We discuss the pectrum of sparticles from this point of view. Some of the sum rules do not depend on the input parameters and can be used to test the consistency of the model, while others are useful in determining the input parameters of the theory. If supersymmetry is discovered but the sum rules turn out to be violated, it will be evidence of new physics beyond the minimal supersymmetric standard model with universal soft supersymmetry-breaking terms.Comment: 25 pages. NUB-3067-93TH, UFIFT-HEP-93-16, SSCL-Preprint-439, June 199