1,045 research outputs found
On a class of linearizable Monge-Amp\`ere equations
Monge-Amp\`ere equations of the form,
arise in many areas of fluid and solid mechanics. Here it is shown that in the
special case , where denotes an arbitrary function,
the Monge-Amp\`ere equation can be linearized by using a sequence of Amp\`ere,
point, Legendre and rotation transformations. This linearization is a
generalization of three examples from finite elasticity, involving plane strain
and plane stress deformations of the incompressible perfectly elastic Varga
material and also relates to a previous linearization of this equation due to
Khabirov [7]
Two views on neutral money: Wieser and Hayek versus Menger and Mises
Neutral money plays a central role in contemporary macroeconomic theory, and is a live issue in recent monetary policy discussions. We challenge the opinion that Hayek’s writings on neutral money have been influenced by, and are similar to, the work of Menger and Mises. We show, first, the significant alternative influence of Friedrich von Wieser on Hayek’s work on the subject. Second, we rehabilitate a neglected method of monetary theorizing specific to Menger and Mises that rejects money neutrality both as a tool for investigating monetary phenomena and as the standard by which monetary regimes, and the market economy itself, should be evaluated. Examining this chapter in the history of economic thought can aid in a deeper reconsideration of the doctrinal foundations of modern monetary theory and policy
Extreme fluctuations in noisy task-completion landscapes on scale-free networks
We study the statistics and scaling of extreme fluctuations in noisy
task-completion landscapes, such as those emerging in synchronized
distributed-computing networks, or generic causally-constrained queuing
networks, with scale-free topology. In these networks the average size of the
fluctuations becomes finite (synchronized state) and the extreme fluctuations
typically diverge only logarithmically in the large system-size limit ensuring
synchronization in a practical sense. Provided that local fluctuations in the
network are short-tailed, the statistics of the extremes are governed by the
Gumbel distribution. We present large-scale simulation results using the exact
algorithmic rules, supported by mean-field arguments based on a coarse-grained
description.Comment: 16 pages, 6 figures, revte
Mobility induces global synchronization of oscillators in periodic extended systems
We study synchronization of locally coupled noisy phase oscillators which
move diffusively in a one-dimensional ring. Together with the disordered and
the globally synchronized states, the system also exhibits several wave-like
states which display local order. We use a statistical description valid for a
large number of oscillators to show that for any finite system there is a
critical spatial diffusion above which all wave-like solutions become unstable.
Through Langevin simulations, we show that the transition to global
synchronization is mediated by the relative size of attractor basins associated
to wave-like states. Spatial diffusion disrupts these states and paves the way
for the system to attain global synchronization
Ludwig von Mises and the 'Ordo-Interventionists' More than Just Aggression and Contempt?
This paper explores the four decades of intellectual relationship between the Austrian School economist Ludwig von Mises (1881-1973) and two major representatives of German ordoliberalism, Walter Eucken (1891-1950) and Wilhelm Röpke (1899-1966). The timespan covered starts in the early 1920s and terminates with Röpke's passing in 1966, a period featuring numerous encounters in person and several debates in published works, accompanied by exchange in correspondence. The central goal of the paper is to provide a more nuanced understanding of the reasons for the hostile climate and the confrontation patterns than earlier narratives in secondary literature. A key tool is the technique of embedding the scholarly component of the interactions into a complex network of interpersonal relationships. The four decades are separated into five distinct phases with differently nuanced communication patterns: 1) early socialization echoing the animosities between the Austrian School and the Historical School; 2) initial debates in the 1920s and early 1930s on business cycle theory and policy where seniority and maturity play an important role; 3) clashes on political economy and social philosophy at the Colloque Walter Lippmann in 1938 and during the two initial decades of the Mont Pèlerin Society after 1947; 4) coexistence during the German "economic miracle"; 5) exchanges in the 1960s, including a discussion of archival materials never published before about Mises' only honorary doctorate in economics, awarded to him by the University of Freiburg in 1964. Based on this historical account at the heart of the paper, conjectures are formulated as to why - despite the common ground in the inquiries pursued - the protagonists continuously fail to engage in more fruitful scholarly debates, and hypotheses are formulated about the substantive core at stake. In addition, a critical overview of selected strands within the extensive historiographic literature exploring the Austrian School and ordoliberalism in recent decades is provided, including a specific reading of the concept of neoliberalism
High shock release in ultrafast laser irradiated metals: Scenario for material ejection
We present one-dimensional numerical simulations describing the behavior of
solid matter exposed to subpicosecond near infrared pulsed laser radiation. We
point out to the role of strong isochoric heating as a mechanism for producing
highly non-equilibrium thermodynamic states. In the case of metals, the
conditions of material ejection from the surface are discussed in a
hydrodynamic context, allowing correlation of the thermodynamic features with
ablation mechanisms. A convenient synthetic representation of the thermodynamic
processes is presented, emphasizing different competitive pathways of material
ejection. Based on the study of the relaxation and cooling processes which
constrain the system to follow original thermodynamic paths, we establish that
the metal surface can exhibit several kinds of phase evolution which can result
in phase explosion or fragmentation. An estimation of the amount of material
exceeding the specific energy required for melting is reported for copper and
aluminum and a theoretical value of the limit-size of the recast material after
ultrashort laser irradiation is determined. Ablation by mechanical
fragmentation is also analysed and compared to experimental data for aluminum
subjected to high tensile pressures and ultrafast loading rates. Spallation is
expected to occur at the rear surface of the aluminum foils and a comparison
with simulation results can determine a spall strength value related to high
strain rates
Commensurability and beyond: from Mises and Neurath to the future of the socialist calculation debate
Mises' 'calculation argument' against socialism argues that monetary calculation is indispensable as a commensurable unit for evaluating factors of production. This is not due to his conception of rationality being purely 'algorithmic,' for it accommodates non-monetary, incommensurable values. Commensurability is needed, rather, as an aid in the face of economic complexity. The socialist Neurath's response to Mises is unsatisfactory in rejecting the need to explore possible non-market techniques for achieving a certain degree of commensurability. Yet Neurath's contribution is valuable in emphasizing the need for a balanced, comparative approach to the question of market versus non-market that puts the commensurability question in context. These central issues raised by adversaries in the early socialist calculation debate have continued relevance for the contemporary discussion
Quantum-like Representation of Extensive Form Games: Wine Testing Game
We consider an application of the mathematical formalism of quantum mechanics
(QM) outside physics, namely, to game theory. We present a simple game between
macroscopic players, say Alice and Bob (or in a more complex form - Alice, Bob
and Cecilia), which can be represented in the quantum-like (QL) way -- by using
a complex probability amplitude (game's ``wave function'') and noncommutative
operators. The crucial point is that games under consideration are so called
extensive form games. Here the order of actions of players is important, such a
game can be represented by the tree of actions. The QL probabilistic behavior
of players is a consequence of incomplete information which is available to
e.g. Bob about the previous action of Alice. In general one could not construct
a classical probability space underlying a QL-game. This can happen even in a
QL-game with two players. In a QL-game with three players Bell's inequality can
be violated. The most natural probabilistic description is given by so called
contextual probability theory completed by the frequency definition of
probability
- …