Thermodynamic anomalies in the presence of dissipation: from the free particle to the harmonic oscillator

A free particle coupled to a heat bath can exhibit a number of thermodynamic anomalies like a negative specific heat or reentrant classicality. These low-temperature phenomena are expected to be modified at very low temperatures where finite-size effects associated with the discreteness of the energy spectrum become relevant. In this paper, we explore in which form the thermodynamic anomalies of the free damped particle appear for a damped harmonic oscillator. Since the discreteness of the oscillator's energy spectrum is fully accounted for, the results are valid for arbitrary temperatures. As expected, they are in agreement with the third law of thermodynamics and indicate how the thermodynamic anomalies of the free damped particle can be reconciled with the third law. Particular attention is paid to the transition from the harmonic oscillator to the free particle when the limit of the oscillator frequency to zero is taken.Comment: 10 pages, 5 figure

Automatic end tool alignment through plane detection with a RANSAC-algorithm for robotic grasping

Camera based grasping algorithms enable the handling of unknown objects without a complete CAD model. In some scenarios, the captured information from a single view is not sufficient or no grasp is possible. For these cases, the precise realignment of the gripper is difficult because a suitable rotation is part of an infinite solution space. In this paper, we propose a framework which automatically identifies correct rotations from point clouds to adjust the gripper. We validate our approach in a virtual environment for a parallel jaw gripper with multiple isolated and grouped industrial objects

Commentary of a critical observer responding to casual encounters

1988 Fall.To view the abstract please see the full text of the document

"Endogenous Uncertainty and Credit Crunches"

We develop a theory of endogenous uncertainty where the ability of investors to learn about firm-level fundamentals declines during financial crises. At the same time, higher uncertainty reinforces financial distress of firms, giving rise to “belief traps”— a persistent cycle of uncertainty, pessimistic expectations, and financial constraints, through which a temporary shortage of funds can develop into a long-lasting funding problem for firms. At the macro-level, belief traps provide a rationale for the long-lasting recessions that typically entail financial crises. In our model, financial crises are characterized by high levels of credit misallocation, an increased cross-sectional dispersion of growth rates, endogenously increased pessimism, uncertainty and disagreement among investors, highly volatile asset prices, and high risk premia. A calibration of our model to U.S. micro data on investor beliefs matches the slow recovery after the 08/09 crisis remarkably well

Endogenous Uncertainty and Credit Crunches

We develop a theory of endogenous uncertainty where the ability of investors to learn about firm-level fundamentals declines during financial crises. At the same time, higher uncertainty reinforces financial distress, causing a persistent cycle of uncertainty, pessimistic expectations, and financial constraints. Through this channel, a temporary shortage of funds can develop into a long-lasting funding problem for firms. Financial crises are characterized by increased credit misallocation, volatile asset prices, high risk premia, an increased cross-sectional dispersion of returns, and high levels of disagreement among forecasters. A numerical example suggests that the proposed channel may significantly delay recovery from financial shocks

Endogenous Second Moments: A Unified Approach to Fluctuations in Risk, Dispersion, and Uncertainty

Many important statistics in macroeconomics and finance—such as cross-sectional dispersions, risk, volatility, or uncertainty—are second moments. In this paper, we explore a mechanism by which second moments naturally and endogenously fluctuate over time as nonlinear transformations of fundamentals. Specifically, we provide general results that characterize second moments of transformed random variables when the underlying fundamentals are subject to distributional shifts that affect their means, but not their variances. We illustrate the usefulness of our results with a series of applications to (1) the cyclicality of the cross-sectional dispersions of macroeconomic variables, (2) the dispersion of MRPKs, (3) security pricing, and (4) endogenous uncertainty in Bayesian inference problems

Endogenous Second Moments: A Unified Approach to Fluctuations in Risk, Dispersion, and Uncertainty

Many important statistics in macroeconomics and finance—such as cross-sectional dispersions, risk, volatility, or uncertainty—are second moments. In this paper, we explore a mechanism by which second moments naturally and endogenously fluctuate over time as nonlinear transformations of fundamentals. Specifically, we provide general results that characterize second moments of transformed random variables when the underlying fundamentals are subject to distributional shifts that affect their means, but not their variances. We illustrate the usefulness of our results with a series of applications to (1) the cyclicality of the cross-sectional dispersions of macroeconomic variables, (2) the dispersion of MRPKs, (3) security pricing, and (4) endogenous uncertainty in Bayesian inference problems

Omar und Leila : eine romantische Oper in 3 Acten / in Musik gesetzt von F. E. Fesca. [Text] von L. Robert. Vollst. vom Comp. verfertigter Clavierausz.

INHALT Atto I Overtura 1. Intr. Rec . ed Aria. lch fürcht' euch nicht, ihr Götter. 2. Rec. Aria e Coro. Genossen der Nacht ! 3. Romanze. Dort in der Laub' am Gitter 4. Terzetto e Coro. Meine Taube ! 5. Duetto . Zerbinchen, Zerbinchen! 6. Finale. Leela, hör' ! Atto II 7. Aria e Coro. Leise von Ort zu Ort 8. Rec. ed Aria. Wär sie am Leben nur 9. Aria. Die Katz' die in die Küche kommt 10. Cavatina. 11. Terzetto e Coro. Herbei, ihr Geister 12. Duetto e Coro. Hört uns da unten! 13. Finale. Nein,nein! wenn ich von hier Atto III 14. Intr. Aria con Coro. Habt ihr das Werk begonnen? 15. Marcia e Coro . Der Gott der Schlachten 16. Romanze. Wenn ich mich peinlich quäle 17. Rec. e Quintetto. Nein, du kennst nicht meine Leiden! 18. Duetto. Bist du's der mich einst entzückte? 19. Aria con Coro. Herbei, ihr Geister! 20. Finale. Omar! höre! 21. Aria (eingelegt.) Ihr erhabnen Himmelsmächt