180 research outputs found
Risk-shifting Through Issuer Liability and Corporate Monitoring
This article explores how issuer liability re-allocates fraud risk and how risk allocation may reduce the incidence of fraud. In the US, the apparent absence of individual liability of officeholders and insufficient monitoring by insurers under-mine the potential deterrent effect of securities litigation. The underlying reasons why both mechanisms remain ineffective are collective action problems under the prevailing dispersed ownership structure, which eliminates the incentives to moni-tor set by issuer liability. This article suggests that issuer liability could potentially have a stronger deterrent effect when it shifts risk to individuals or entities holding a larger financial stake. Thus, it would enlist large shareholders in monitoring in much of Europe. The same risk-shifting effect also has implications for the debate about the relationship between securities litigation and creditor interests. Credi-tors’ claims should not be given precedence over claims of defrauded investors (e.g., because of the capital maintenance principle), since bearing some of the fraud risk will more strongly incentivise large creditors, such as banks, to monitor the firm in jurisdictions where corporate debt is relatively concentrated
Deformation of canonical morphisms and the moduli of surfaces of general type
In this article we study the deformation of finite maps and show how to use
this deformation theory to construct varieties with given invariants in a
projective space. Among other things, we prove a criterion that determines when
a finite map can be deformed to a one--to--one map. We use this criterion to
construct new simple canonical surfaces with different and . Our
general results enable us to describe some new components of the moduli of
surfaces of general type. We also find infinitely many moduli spaces having one component whose general point corresponds to a
canonically embedded surface and another component whose general point
corresponds to a surface whose canonical map is a degree 2 morphism.Comment: 32 pages. Final version with some simplifications and clarifications
in the exposition. To appear in Invent. Math. (the final publication is
available at springerlink.com
Fibonacci numbers and self-dual lattice structures for plane branches
Consider a plane branch, that is, an irreducible germ of curve on a smooth
complex analytic surface. We define its blow-up complexity as the number of
blow-ups of points necessary to achieve its minimal embedded resolution. We
show that there are topological types of blow-up complexity ,
where is the -th Fibonacci number. We introduce
complexity-preserving operations on topological types which increase the
multiplicity and we deduce that the maximal multiplicity for a plane branch of
blow-up complexity is . It is achieved by exactly two topological
types, one of them being distinguished as the only type which maximizes the
Milnor number. We show moreover that there exists a natural partial order
relation on the set of topological types of plane branches of blow-up
complexity , making this set a distributive lattice, that is, any two of its
elements admit an infimum and a supremum, each one of these operations beeing
distributive relative to the second one. We prove that this lattice admits a
unique order-inverting bijection. As this bijection is involutive, it defines a
duality for topological types of plane branches. The type which maximizes the
Milnor number is also the maximal element of this lattice and its dual is the
unique type with minimal Milnor number. There are self-dual
topological types of blow-up complexity . Our proofs are done by encoding
the topological types by the associated Enriques diagrams.Comment: 21 pages, 16 page
Homological Type of Geometric Transitions
The present paper gives an account and quantifies the change in topology
induced by small and type II geometric transitions, by introducing the notion
of the \emph{homological type} of a geometric transition. The obtained results
agree with, and go further than, most results and estimates, given to date by
several authors, both in mathematical and physical literature.Comment: 36 pages. Minor changes: A reference and a related comment in Remark
3.2 were added. This is the final version accepted for publication in the
journal Geometriae Dedicat
Pasquale del Pezzo, Duke of Caianello, Neapolitan mathematician
This article is dedicated to a reconstruction of some events and achievements, both personal and scientific, in the life of the Neapolitan mathematician Pasquale del Pezzo, Duke of Caianello
Interacting Preformed Cooper Pairs in Resonant Fermi Gases
We consider the normal phase of a strongly interacting Fermi gas, which can
have either an equal or an unequal number of atoms in its two accessible spin
states. Due to the unitarity-limited attractive interaction between particles
with different spin, noncondensed Cooper pairs are formed. The starting point
in treating preformed pairs is the Nozi\`{e}res-Schmitt-Rink (NSR) theory,
which approximates the pairs as being noninteracting. Here, we consider the
effects of the interactions between the Cooper pairs in a Wilsonian
renormalization-group scheme. Starting from the exact bosonic action for the
pairs, we calculate the Cooper-pair self-energy by combining the NSR formalism
with the Wilsonian approach. We compare our findings with the recent
experiments by Harikoshi {\it et al.} [Science {\bf 327}, 442 (2010)] and
Nascimb\`{e}ne {\it et al.} [Nature {\bf 463}, 1057 (2010)], and find very good
agreement. We also make predictions for the population-imbalanced case, that
can be tested in experiments.Comment: 10 pages, 6 figures, accepted version for PRA, discussion of the
imbalanced Fermi gas added, new figure and references adde
Four lectures on secant varieties
This paper is based on the first author's lectures at the 2012 University of
Regina Workshop "Connections Between Algebra and Geometry". Its aim is to
provide an introduction to the theory of higher secant varieties and their
applications. Several references and solved exercises are also included.Comment: Lectures notes to appear in PROMS (Springer Proceedings in
Mathematics & Statistics), Springer/Birkhause
Corporate Governance, Capital Market Regulation and the Challenge of Disembedded Markets
Contextualizing legal norms: a multi-dimensional view of the 2014 legal capital reform in China
This paper intends to shed light on the contentious theme of the reception of legal transplantation in the host environment, by examining the 2014 legislative reform of legal capital in China, which at least on paper imitates the enabling settings of US Revised Model Business Corporation Act (RMBCA). The paper looks at the interconnections between national-specific contextual elements, the resultant complexities, and the spillover effects of transplanted configurations in the unique Chinese socio-cultural setting, implicating the discrepancy between the ‘law in practice’ and the borrowed words ‘on the books’, and suggesting the importance of gaining a holistic understanding of ‘law’ involving the legal traditions in both the donor country and the recipient nation
Histological study of the liver and biochemistry of the blood of Wistar rats following ligature of right hepatic duct
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