Sergio Pernice

Supersymmetry and singular potentials

Abstract The breaking of supersymmetry due to singular potentials in supersymmetric quantum mechanics is critically analyzed. It is shown that, when properly regularized, these potentials respect supersymmetry, even when the regularization parameter is removed.

Matching Current Correlators in Lattice QCD to Chiral Perturbation Theory

Chiral perturbation theory gives direct and unambiguous predictions for the form of various two-point hadronic correlators at low momentum in terms of a finite set of couplings in a chiral Lagrangian. In this paper we study the feasibility of extracting the couplings in the chiral Lagrangian (through 1-loop order) by fitting two-point correlators computed in lattice QCD to the predicted chiral form. The correlators are computed using a pseudofermion technique yielding all-point quark propagators which allows the computation of the full four-momentum transform of the two-point functions to be obtained without sacrificing any of the physical content of the unquenched gauge configurations used. Results are given for an ensemble of dynamical configurations generated using the truncated determinant algorithm on a large coarse lattice. We also present a new analysis of finite volume effects based on a finite volume dimensional regularization scheme which preserves the power-counting rules appropriate for a chiral Lagrangian.

Determinants of the Development of Corporate Bond Markets in Argentina: One Size Does Not Fit All

Conventional theory leads to expect bonds to be a financing vehicle for large firms because of economies of scale and contracting costs. We find both in our econometric evidence for firms quoted on Latin American stock exchanges, and in our survey results for Argentina, that size of assets is a robust determinant of the use of bond finance. This result, together with the fact that there are few firms that are large in terms of market value, can help understand why Argentina, as well as Latin America, has small bond markets in terms of the ratio of the stock of bonds to GDP. Since firm value represents the present value of the cash flows against which the firm borrows, the outstanding stock of corporate bonds is as small as the size of Argentine firms.

Culture and Social Resistance to Reform: A Theory About the Endogeneity of Public Beliefs With an Application to the Case of Argentina

This paper attempts to understand the factors that explain the degree of support or criticism that a reform process may be subject to. Understanding these determinants is critical, in turn, to assess the feasibility and sustainability of those reforms. In particular, we want to assess what are the elements that create societal consensus for reform and which are the main factors that turn public opinion against it. In the case of Argentina, for example, such dynamics are critical to understand how public opinion imposed constraints on government behavior, affected macroeconomic performance, and ultimately, determined the chance of success of reforms.

Loan and Bond Finance in Argentina, 1985-2005

Loan and bond finance during 1985-2005 can be divided into three sub-periods. After the 1982 debt crisis, which mainly involved domestic and foreign bank loans to both the corporate and government sectors, there was practically no credit. This situation of lack of credit persisted until the domestic economy was stabilized in 1991 with the Convertibility Plan, and foreign debt renegotiation was completed in 1993 with the Brady Plan. Loan finance recovered to unprecedented levels since the 1950s, and bond finance became for the first time an important financing vehicle for both the national government and large firms in the corporate sector. Credit came to a sudden stop in 2001, with widespread default on both corporate and government bonds. The 2001 debt crisis was not followed by runaway domestic inflation, and by 2005 Argentina was able to return to foreign capital markets.

Valuation of Debt Indexed to Real Values I. The case of the Argentinean Growth Coupon: a Simple Mode

This paper is the first of a series of works whose aim is trying to provide a framework for the understanding and valuation of debt indexed to real (generally non-tradable) variables. In particular, in the present paper we develop a methodology to analytically value the new GDP-linked Argentinean warrant.

Analysis of Latin America's Corporations as a Rational Response to the Economic Environment Present in the Region - Part I

This is the first of a series of working papers analyzing the basic characteristics of the economic environment in which Latin American Corporations live and the optimal design of incentive programs compatible with such environment. By economic environment we mean the technology that the organizations have access to, the legal framework present in these countries, the macro-economical characteristics, the markets in which they operate (competitors, monopolies, customers, reliability of suppliers, etc.), the nature of their capital markets and in general of the sources of financing for their companies, etc. We could broadly say that any key feature of the economy that has the potential to influence the way business is run in Latin America is part of its economic environment. The underlying unifying idea in this series is that, unless we have clear evidence to the contrary, corporate practices observed in Latin American firms are rational responses to the environment in which they operate. They are a sort of Darwinian adaptation to such environment. Therefore, much like in biological systems, these characteristics of corporations should be considered optimal in a relative sense. That is, in order to survive in the market, the observed corporate practices should be better that the ones from the competition for the given economic environment. This observation suggests that improvements to the observed practices are indeed possible. In fact, the present series of working papers is in part structured to explore possible improvements. These improvements, however, are not likely to be the simple copy of corporate practices that evolved as an optimal response to the environment of the developed world. In this first work we present some important empirical characteristics of the Latin American Corporations and the first key aspect of the economic environment prevailing in this region: the legal framework. We show how many of the empirical characteristics presented can be see as optimal responses to the legal framework.