Position measurement-induced collapse states are shown to provide a unified quantum description of diffraction of particles passing through a single slit. These states, which we here call ‘quantum location states’, are represented by the conventional rectangular wave function at the initial time of position measurement. We expand this state in terms of the position eigenstates, which in turn can be represented as a linear combination of energy eigenfunctions of the problem, using the closure property. The time-evolution of the location states (...) in the case of free particles is shown to have position probability density patterns closely resembling diffraction patterns in the Fresnel region for small times and the same in Fraunhofer region for large times. Using the quantum trajectory representations in the de Broglie–Bohm, modified de Broglie–Bohm and Floyd–Faraggi–Matone formalisms, we show that Fresnel and Fraunhofer diffractions can be described using a single expression. We also discuss how to obtain the probability density of location states for the case of particles moving in a general potential, detected at some arbitrary point. In the case of the harmonic oscillator potential, we find that they have oscillatory properties similar to that of coherent states. (shrink)
Plant‐specific NAC transcription factors (TFs) evolve during the transition from aquatic to terrestrial plant life and are amplified to become one of the biggest TF families. This is because they regulate genes involved in water conductance and cell support. They also control flower and fruit formation. The review presented here focuses on various properties, regulatory intricacies, and developmental roles of NAC family members. Processes controlled by NACs depend majorly on their transcriptional properties. NACs can function as both activators and/or repressors. (...) Additionally, their homo/hetero dimerization abilities can also affect DNA binding and activation properties. The active protein levels are dependent on the regulatory cascades. Because NACs regulate both development and stress responses in plants, in‐depth knowledge about them has the potential to help guide future crop improvement studies. (shrink)
This paper examines the nature of classical correspondence in the case of coherent states at the level of quantum trajectories. We first show that for a harmonic oscillator, the coherent state complex quantum trajectories and the complex classical trajectories are identical to each other. This congruence in the complex plane, not restricted to high quantum numbers alone, illustrates that the harmonic oscillator in a coherent state executes classical motion. The quantum trajectories we consider are those conceived in a modified de (...) Broglie-Bohm scheme. Though quantum trajectory representations are widely discussed in recent years, identical classical and quantum trajectories for coherent states are obtained only in the present approach. We may note that this result for standard harmonic oscillator coherent states is not totally unexpected because of their holomorphic nature. The study is extended to coherent states of a particle in an infinite potential well and that in a symmetric Poschl-Teller potential by solving for the trajectories numerically. For the Gazeau-Klauder coherent state of the infinite potential well, almost identical classical and quantum trajectories are obtained whereas for the Poschl-Teller potential, though classical trajectories are not regained, a periodic motion results as t→∞. Similar features were found for the SUSY quantum mechanics-based coherent states of the Poschl-Teller potential too, but this time the pattern of complex trajectories is quite different from that of the previous case. Thus we find that the method is a potential tool in analyzing the properties of generalized coherent states. (shrink)
Experiments are not models of cooperation; instead, they demonstrate the presence of the ethical and other-regarding predispositions that often motivate cooperation and the punishment of free-riders. Experimental behavior predicts subjects' cooperation in the field. Ethnographic studies in small-scale societies without formal coercive institutions demonstrate that disciplining defectors is both essential to cooperation and often costly to the punisher.
Does Josiah Royce's defense of loyalty hold any relevance for us in the twenty-first century? Mathew A. Foust thinks that it does. Business ethics, the ethics of warfare, and moral interpretation of twenty-first-century fiction: these are the three areas where Foust applies a Roycean understanding of loyalty. While Foust offers a persuasive case for the relevance and viability of Royce's account of loyalty in the twenty-first century, my primary criticism of Foust's book concerns his acceptance of Royce's equation of (...) duties and virtues. In what follows, I contextualize Royce's understanding of loyalty in relation to the political and social philosophy developed late in his writing career; I explain... (shrink)