On the Emergence of the Microcanonical Description from a Pure State

We study, in general terms, the process by which a pure state can ``self-thermalize'' and {\em appear} to be described by a microcanonical density matrix. This requires a quantum mechanical version of the Gibbsian coarse graining that conceptually underlies classical statistical mechanics. We introduce some extra degrees of freedom that are necessary for this. Interaction between these degrees and the system can be understood as a process of resonant absorption and emission of ``soft quanta''. This intuitive picture allows one to state a criterion for when self thermalization occurs. This paradigm also provides a method for calculating the thermalization rate using the usual formalism of atomic physics for calculating decay rates. We contrast our prescription for coarse graining, which is somewhat dynamical, with the earlier approaches that are intrinsically kinematical. An important motivation for this study is the black hole information paradox.Comment: 58 pages, 2 figures. A reference adde

DESIGN, FABRICATION, AND CHARACTERIZATION OF SINGLE CRYSTAL SILICON LATCHINGSNAP FASTENERS FOR MICRO ASSEMBLY

A snap fastener is a deformable device consisting of a pair of mating surfaces that "snap" together during assembly. Because of the simple, linear assembly motion, such latching micro fasteners have a wide range of applications in micro assembly tasks, e.g.\ for devices with multiple or layered components, or micro opto-mechanical plugs. At the micro scale, conventional types of fasteners like screws and hinges are unlikely to work due to present fabrication constraints and large friction forces. Micro snap fasteners also have great potential to be used as sensors with memory

Nonextensive thermodynamic relations

The generalized zeroth law of thermodynamics indicates that the physical temperature in nonextensive statistical mechanics is different from the inverse of the Lagrange multiplier, beta. This leads to modifications of some of thermodynamic relations for nonextensive systems. Here, taking the first law of thermodynamics and the Legendre transform structure as the basic premises, it is found that Clausius definition of the thermodynamic entropy has to be appropriately modified, and accordingly the thermodynamic relations proposed by Tsallis, Mendes and Plastino [Physica A 261 (1998) 534] are also to be rectified. It is shown that the definition of specific heat and the equation of state remain form invariant. As an application, the classical gas model is reexamined and, in marked contrast with the previous result obtained by Abe [Phys. Lett. A 263 (1999) 424: Erratum A 267 (2000) 456] using the unphysical temperature and the unphysical pressure, the specific heat and the equation of state are found to be similar to those in ordinary extensive thermodynamics.Comment: 17 pages. The discussion about the Legendre transform structure is modified and some additional comments are mad

Variational Calculations for 3^3He Impurities on 4^4He Droplets

Variational Monte Carlo method is used to calculate ground state properties of $^4$He droplets, containing 70, 112, 168, 240, 330, and 728 particles. The resulting particle and kinetic energy densities are used as an input in the Feynman-Lekner theory for $^3$He impurities. The kinetic energy density of $^4$He atoms and the energy of the $^3$He surface states are compared with the results of previous phenomenological calculations.Comment: 12 pages, in revtex 3.0, with 5 .ps figure

The Effect of Space Planting on Growth of Mangrove (Avicennia Marina) Seedlings in the Anak Setatah Village, West Rangsang District Meranti Archipelago Riau Province

This research was conducted in Febuary - April 2016 at Anak Setatah Village, West Rangsang District Meranti Archipelagos Riau Province. This study aims to determine the effect of spacing on seedling height, survival rateand leave number of A. marina. The method used was experiment method. Planting space treatment were 25, 50 and 75 cm. The result for 60 days of observation show that the best space in high found in plant spacing 75 cm with a value of 26,04 cm/60 days, and the best growth for diameter was at space of 25 cm, with a stem diameter growth of 0.41 cm/60 days. The highest number of leaves in a spacing of 75 cm. The Anova test results that spasing planting given effect to height grow, stem diameter, and total number of leafs A. marina. Student- Newman- Keuls test show that treatment 25 cm is diffirent with 50 cm, and 75 cm, but treatment 50 cm is not diffirent with 75cm

Cálculo de los tiempos de circularvección en una población con patología vestibular. Influencia del estímulo visual

[corrected] To describe the results obtained for circularvection times (tCV) in a study of the phenomenon of visual-vestibular interaction for a population with vestibular pathology and to analyze differences in its calculation among patients reporting a worsening of their symptoms with visual stimuli. MATERIAL AND METHODS: A detailed case history was taken for all patients, followed by a sensory organization test using computerized dynamic posturography and the calculation of their tCV. RESULTS: The mean tCV results were: tCV2= 6.32+/-3.17 s; tCV3=6.57+/-3.68 s; tCVr=6.27+/-6.02 s. Significant differences were obtained in tCV2 (P=.046) and tCVr (P=.023). CONCLUSIONS: tCV is a diagnostic test using simple tools that can help differentiate patients in whom the visual stimulus is influenced

Thermodynamics' 0-th-Law in a nonextensive scenario

Tsallis' thermostatistics is by now recognized as a new paradigm for statistical mechanical considerations. However, it is still affected by a serious hindrance: the generalization of thermodynamics' zero-th law to a nonextensive scenario is plagued by difficulties. Here we show how to overcome this problem.Comment: 4 pages, latex; added references for section