Risk-Adjusted Inside Debt

Compensation theory holds that executive aggression is related to both the level and riskiness of “inside debt” - promises from firms to pay their executives fixed sums of cash in the future, including pensions and deferred compensation. However, previous researchers have only examined the level of inside debt. We provide an inside debt metric that is conceptually superior to previously used metrics, as it incorporates the riskiness of inside debt. For the entire sample, our metric offers modest improvement in fit over past metrics, where the dependent variable is future equity return volatility. Furthermore, the relation between future volatility and our risk-adjusted inside debt metric is more prominent for non-investment grade firms, firms experiencing credit rating downgrades, and firms with high credit risk

Von Neumann Entropy-Preserving Quantum Operations

For a given quantum state $\rho$ and two quantum operations $\Phi$ and $\Psi$, the information encoded in the quantum state $\rho$ is quantified by its von Neumann entropy $\S(\rho)$. By the famous Choi-Jamio{\l}kowski isomorphism, the quantum operation $\Phi$ can be transformed into a bipartite state, the von Neumann entropy $\S^{\mathrm{map}}(\Phi)$ of the bipartite state describes the decoherence induced by $\Phi$. In this Letter, we characterize not only the pairs $(\Phi, \rho)$ which satisfy $\S(\Phi(\rho))=\S(\rho)$, but also the pairs $(\Phi, \Psi)$ which satisfy $\S^{\mathrm{map}}(\Phi\circ\Psi) = \S^{\mathrm{map}}(\Psi)$.Comment: 7 pages, LaTeX, to appear Phys. Lett.

Saturation of dephasing time in mesoscopic devices produced by a ferromagnetic state

We consider an exchange model of itinerant electrons in a Heisenberg ferromagnet and we assume that the ferromagnet is in a fully polarized state. Using the Holstein-Primakoff transformation we are able to obtain a boson-fermion Hamiltonian that is well-known in the interaction between light and matter. This model describes the spontaneous emission in two-level atoms that is the proper decoherence mechanism when the number of modes of the radiation field is taken increasingly large, the vacuum acting as a reservoir. In the same way one can see that the interaction between the bosonic modes of spin waves and an itinerant electron produces decoherence by spin flipping with a rate proportional to the size of the system. In this way we are able to show that the experiments on quantum dots, described in D. K. Ferry et al. [Phys. Rev. Lett. {\bf 82}, 4687 (1999)], and nanowires, described in D. Natelson et al. [Phys. Rev. Lett. {\bf 86}, 1821 (2001)], can be understood as the interaction of itinerant electrons and an electron gas in a fully polarized state.Comment: 10 pages, no figure. Changed title. Revised version accepted for publication in Physical Review

The Nature of the Chemical Process. 1. Symmetry Evolution - Revised Information Theory, Similarity Principle and Ugly Symmetry

Three laws of information theory have been proposed. Labeling by introducing nonsymmetry and formatting by introducing symmetry are defined. The function L (L=lnw, w is the number of microstates, or the sum of entropy and information, L=S+I) of the universe is a constant (the first law of information theory). The entropy S of the universe tends toward a maximum (the second law law of information theory). For a perfect symmetric static structure, the information is zero and the static entropy is the maximum (the third law law of information theory). Based on the Gibbs inequality and the second law of the revised information theory we have proved the similarity principle (a continuous higher similarity-higher entropy relation after the rejection of the Gibbs paradox) and proved the Curie-Rosen symmetry principle (a higher symmetry-higher stability relation) as a special case of the similarity principle. Some examples in chemical physics have been given. Spontaneous processes of all kinds of molecular interaction, phase separation and phase transition, including symmetry breaking and the densest molecular packing and crystallization, are all driven by information minimization or symmetry maximization. The evolution of the universe in general and evolution of life in particular can be quantitatively considered as a series of symmetry breaking processes. The two empirical rules - similarity rule and complementarity rule - have been given a theoretical foundation. All kinds of periodicity in space and time are symmetries and contribute to the stability. Symmetry is beautiful because it renders stability. However, symmetry is in principle ugly because it is associated with information loss.Comment: 29 pages, 14 figure

Multicommodity Flow Problems with Commodity Compatibility Relations

We present a class of Multicommodity Flow Problems with Commodity Compatibility Relations (MCFP-CCR), in which compatibility relations among commodities used at each node are required. This class of problems has application in the Train Unit Scheduling Problem (TUSP) [1, 2], where train units of different traction types may not be coupled with each other to serve the same train trip. Computational complexity issues are discussed and solution methods are proposed. Computational experiments using the proposed solution methods are reported

Risk-Adjusted Inside Debt

Compensation theory holds that executive aggression is related to both the level and riskiness of “inside debt” - promises from firms to pay their executives fixed sums of cash in the future, including pensions and deferred compensation. However, previous researchers have only examined the level of inside debt. We provide an inside debt metric that is conceptually superior to previously used metrics, as it incorporates the riskiness of inside debt. For the entire sample, our metric offers modest improvement in fit over past metrics, where the dependent variable is future equity return volatility. Furthermore, the relation between future volatility and our risk-adjusted inside debt metric is more prominent for non-investment grade firms, firms experiencing credit rating downgrades, and firms with high credit risk

Interventions to promote cycling: systematic review

Objectives To determine what interventions are effective in promoting cycling, the size of the effects of interventions, and evidence of any associated benefits on overall physical activity or anthropometric measures