528 research outputs found
On the "Universal" N=2 Supersymmetry of Classical Mechanics
In this paper we continue the study of the geometrical features of a
functional approach to classical mechanics proposed some time ago. In
particular we try to shed some light on a N=2 "universal" supersymmetry which
seems to have an interesting interplay with the concept of ergodicity of the
system. To study the geometry better we make this susy local and clarify
pedagogically several issues present in the literature. Secondly, in order to
prepare the ground for a better understanding of its relation to ergodicity, we
study the system on constant energy surfaces. We find that the procedure of
constraining the system on these surfaces injects in it some local grassmannian
invariances and reduces the N=2 global susy to an N=1.Comment: few misprints fixed with respect to Int.Jour.Mod.Phys.A vol 16, no15
(2001) 270
Universal Hidden Supersymmetry in Classical Mechanics and its Local Extension
We review here a path-integral approach to classical mechanics and explore
the geometrical meaning of this construction. In particular we bring to light a
universal hidden BRS invariance and its geometrical relevance for the Cartan
calculus on symplectic manifolds. Together with this BRS invariance we also
show the presence of a universal hidden genuine non-relativistic supersymmetry.
In an attempt to understand its geometry we make this susy local following the
analogous construction done for the supersymmetric quantum mechanics of Witten.Comment: 6 pages, latex, Volkov Memorial Proceeding
Internationalization and the evolution of corporate valuation
By documenting the evolution of Tobin's q before, during, and after firms internationalize, the authors provide evidence on the bonding, segmentation, and market timing theories of internationalization. Using new data on 9,096 firms across 74 countries over the period 1989-2000, they find that Tobin's q does not rise after internationalization, even relative to firms that do not internationalize. Instead, q rises significantly before internationalization and during the internationalization year. But then q falls sharply in the year after internationalization, quickly relinquishing the increases of the previous years. To account for these dynamics, the authors show that market capitalization rises before internationalization and remains high, while corporate assets increase during internationalization. The evidence supports models stressing that financial internationalization facilitates corporate expansion, but challenges models stressing that internationalization produces an enduring effect on q by bonding firms to a better corporate governance system.Small Scale Enterprise,Microfinance,Investment and Investment Climate,Economic Theory&Research,Markets and Market Access
Universal Local symmetries and non-superposition in classical mechanics
In the Hilbert space formulation of classical mechanics (CM), pioneered by
Koopman and von Neumann (KvN), there are potentially more observables that in
the standard approach to CM. In this paper we show that actually many of those
extra observables are not invariant under a set of universal local symmetries
which appear once the KvN is extended to include the evolution of differential
forms. Because of their non-invariance, those extra observables have to be
removed. This removal makes the superposition of states in KvN, and as a
consequence also in CM, impossible
Innovative experiences in access to finance : market friendly roles for the visible hand ?
Interest in access to finance has increased significantly in recent years, as growing evidence suggests that lack of access to credit prevents lower-income households and small firms from financing high return investment projects, having an adverse effect on growth and poverty alleviation. This study describes some recent innovative experiences to broaden access to credit. These experiences are consistent with an emerging new view that recognizes a limited role for the public sector in financial markets, but contends that there might be room for well-designed, restricted interventions in collaboration with the private sector to foster financial development and broaden access. The authors illustrate this view with several recent experiences inLatin America and then discuss some open policy questions about the role of the public and private sectors in driving these financial innovations.Debt Markets,Banks&Banking Reform,,Emerging Markets,Bankruptcy and Resolution of Financial Distress
Capital market development : whither Latin America ?
Over the past decades, many countries have implemented significant reforms to foster capital market development. Latin American countries were at the forefront of this process. The authors analyze where Latin American capital markets stand after these reforms. They find that despite the intense reform effort, capital markets in Latin America remain underdeveloped relative to markets in other regions. Furthermore, stock markets are below what can be expected, given Latin America's economic and institutional fundamentals. The authors discuss alternative ways of interpreting this evidence. They argue that it is difficult to pinpoint which policies Latin American countries should pursue to overcome their poor capital market development. Moreover, they argue that expectations about the outcome of the reform process may need to be revisited to take into account intrinsic characteristics of emerging economies. The latter may limit the scope for developing deep domestic capital markets in a context of international financial integration.Markets and Market Access,Economic Theory&Research,Access to Markets,Financial Economics,Financial Intermediation
Stock market development under globalization : whither the gains from reforms ?
Over the past decades, many countries have implemented significant reforms to foster domestic capital market development. These reforms included stock market liberalization, privatization programs, and the establishment of regulatory and supervisory frameworks. Despite the intense reform efforts, the performance of capital markets in several countries has been disappointing. To study whether reforms have had the intended effects on capital markets, the authors analyze the impact of six capital market reforms on domestic stock market development and internationalization using event studies. They find that reforms tend to be followed by significant increases in domestic market capitalization, trading, and capital raising. Reforms are also followed by an increase in the share of activity in international equity markets, with potential negative spillover effects on domestic markets.Markets and Market Access,Economic Theory&Research,Access to Markets,Privatization,Corporate Law
Quantum mechanics over a q-deformed (0+1)-dimensional superspace
We built up a explicit realization of (0+1)-dimensional q-deformed superspace
coordinates as operators on standard superspace. A q-generalization of
supersymmetric transformations is obtained, enabling us to introduce scalar
superfields and a q-supersymmetric action. We consider a functional integral
based on this action. Integration is implemented, at the level of the
coordinates and at the level of the fields, as traces over the corresponding
representation spaces. Evaluation of these traces lead us to standard
functional integrals. The generation of a mass term for the fermion field
leads, at this level, to an explicitely broken version of supersymmetric
quantum mechanics.Comment: 11 pages, Late
How Firms Use Domestic and International Corporate Bond Markets
This paper provides the first comprehensive documentation of the main features of corporate bond issues in domestic and international markets and analyzes how firms use these markets after they internationalize. We find that debt issues in domestic and international bond markets have different characteristics, not explained by differences across firms or their country of origin. International issues tend to be larger, of shorter maturity, denominated in foreign currency, and include a higher fraction of fixed rate contracts. Moreover, a large proportion of firms remain active in domestic bond markets after accessing international markets, and many of these firms use both markets for different types of issues. This evidence suggests that domestic and international bond markets provide different financial services and are not substitutes, but rather complements.
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