36,594 research outputs found
How Law and Institutions Shape Financial Contracts: The Case of Bank Loans
We examine empirically how legal origin, creditor rights, property rights, legal formalism, and financial development affect the design of price and non-price terms of bank loans in almost 60 countries. Our results support the law and finance view that private contracts reflect differences in legal protection of creditors and the enforcement of contracts. Loans made to borrowers in countries where creditors can seize collateral in case of default are more likely to be secured, have longer maturity, and have lower interest rates. We also find evidence, however, that ?Coasian? bargaining can partially offset weak legal or institutional arrangements. For example, lenders mitigate risks associated with weak property rights and government corruption by securing loans with collateral and shortening maturity. Our results also suggest that the choice of loan ownership structure affects loan contract terms.
A Circumbinary Planet in Orbit Around the Short-Period White-Dwarf Eclipsing Binary RR Cae
By using six new determined mid-eclipse times together with those collected
from the literature, we found that the Observed-Calculated (O-C) curve of RR
Cae shows a cyclic change with a period of 11.9 years and an amplitude of
14.3s, while it undergoes an upward parabolic variation (revealing a long-term
period increase at a rate of dP/dt =+4.18(+-0.20)x10^(-12). The cyclic change
was analyzed for the light-travel time effect that arises from the
gravitational influence of a third companion. The mass of the third body was
determined to be M_3*sin i' = 4.2(+-0.4) M_{Jup} suggesting that it is a
circumbinary giant planet when its orbital inclination is larger than 17.6
degree. The orbital separation of the circumbinary planet from the central
eclipsing binary is about 5.3(+-0.6)AU. The period increase is opposite to the
changes caused by angular momentum loss via magnetic braking or/and
gravitational radiation, nor can it be explained by the mass transfer between
both components because of its detached configuration. These indicate that the
observed upward parabolic change is only a part of a long-period (longer than
26.3 years) cyclic variation, which may reveal the presence of another giant
circumbinary planet in a wide orbit.Comment: It will be published in the MNRA
Fluctuation Theorems of Brownian Particles Controlled by a Maxwell's Demon
We study the stochastic dynamics of Brownian particles in a heat bath and
subject to an active feedback control by an external, Maxwell's demon-like
agent. The agent uses the information of the velocity of a particle and reduces
its thermal agitation by applying a force. The entropy of the particle and the
heat bath as a whole, thus, reduces. Entropy pumping [Phys. Rev. Lett. 93,
120602 (2004)] quantifies the entropy reduction. We discover that the entropy
pumping has a dual role of work and heat contributing to free energy changes
and entropy production of the open-system with the feedback control.
Generalized Jarzynski equality and fluctuation theorems for work functional and
entropy production are developed with the presence of the entropy pumping.Comment: 4 page
Stochastic Thermodynamics Across Scales: Emergent Inter-attractoral Discrete Markov Jump Process and Its Underlying Continuous Diffusion
The consistency across scales of a recently developed mathematical
thermodynamic structure, between a continuous stochastic nonlinear dynamical
system (diffusion process with Langevin or Fokker-Planck equations) and its
emergent discrete, inter-attractoral Markov jump process, is investigated. We
analyze how the system's thermodynamic state functions, e.g. free energy ,
entropy , entropy production , and free energy dissipation ,
etc., are related when the continuous system is describe with a coarse-grained
discrete variable. We show that the thermodynamics derived from the underlying
detailed continuous dynamics is exact in the Helmholtz free-energy
representation. That is, the system thermodynamic structure is the same as if
one only takes a middle-road and starts with the "natural" discrete
description, with the corresponding transition rates empirically determined. By
"natural", we mean in the thermodynamic limit of large systems in which there
is an inherent separation of time scales between inter- and intra-attractoral
dynamics. This result generalizes a fundamental idea from chemistry and the
theory of Kramers by including thermodynamics: while a mechanical description
of a molecule is in terms of continuous bond lengths and angles, chemical
reactions are phenomenologically described by the Law of Mass Action with rate
constants, and a stochastic thermodynamics.Comment: 21 pages, 1 figur
Relative Entropy: Free Energy Associated with Equilibrium Fluctuations and Nonequilibrium Deviations
Using a one-dimensional macromolecule in aqueous solution as an illustration,
we demonstrate that the relative entropy from information theory, , has a natural role in the energetics of equilibrium and
nonequilibrium conformational fluctuations of the single molecule. It is
identified as the free energy difference associated with a fluctuating density
in equilibrium, and is associated with the distribution deviate from the
equilibrium in nonequilibrium relaxation. This result can be generalized to any
other isothermal macromolecular systems using the mathematical theories of
large deviations and Markov processes, and at the same time provides the
well-known mathematical results with an interesting physical interpretations.Comment: 5 page
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