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in subjects: "Entropy"

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Signatures of new phenomena in ultrarelativistic nuclear collisions

Three classes of observables are discussed which may shed light on the properties of the quark-gluon plasma formed in ultrarelativistic nuclear collisions. They are: (1) thermometers: the penetrating probes ..mu../sup +/..mu../sup -/, ..gamma.., c, (2) barometers: transverse flow via <p perpendicular >, and (3) seismometers: fluctuations of dN/dy and dE perpendicular/dy. The need for reliable estimates of the background due to the non-equilibrium processes is emphasized. 49 references.

Date: November 1, 1983

Creator: Gyulassy, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Proximity effect in Cu-Nb-Sn composites

Heat capacities have been measured in the presence of magnetic fields for Cu-Nb and Cu-Nb/sub 3/Sn in situ composites in order to determine the size of the superconducting pair potential which is induced in the normal Cu region as a function of magnetic field. For the Cu-Nb composites the induced pair potential is found to be about 0.35 MeV in zero field, in agreement with de Gennes boundary conditions. With the application of a magnetic field, the energy gap declines quickly and above about 17… more

Date: October 1, 1981

Creator: Shum Eucker, S.S.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

An entropic approach to the analysis of time series.

Statistical analysis of time series. With compelling arguments we show that the Diffusion Entropy Analysis (DEA) is the only method of the literature of the Science of Complexity that correctly determines the scaling hidden within a time series reflecting a Complex Process. The time series is thought of as a source of fluctuations, and the DEA is based on the Shannon entropy of the diffusion process generated by these fluctuations. All traditional methods of scaling analysis, instead, are base… more

Date: December 2001

Creator: Scafetta, Nicola

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Time Reversal Violation

This talk briefly reviews three types of time-asymmetry in physics, which I classify as universal, macroscopic and microscopic. Most of the talk is focused on the latter, namely the violation of T-reversal invariance in particle physics theories. In sum tests of microscopic T-invariance, or observations of its violation, are limited by the fact that, while we can measure many processes, only in very few cases can we construct a matched pair of process and inverse process and observe it with suf… more

Date: January 27, 2009

Creator: Quinn, H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Beyond Boltzmann-Gibbs statistics: Maximum entropy hyperensemblesout-of-equilibrium

What is the best description that we can construct of athermodynamic system that is not in equilibrium, given only one, or afew, extra parameters over and above those needed for a description ofthe same system at equilibrium? Here, we argue the most appropriateadditional parameter is the non-equilibrium entropy of the system, andthat we should not attempt to estimate the probability distribution ofthe system, but rather the metaprobability (or hyperensemble) that thesystem is described by a par… more

Date: February 23, 2006

Creator: Crooks, Gavin E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Entropy of near-extremal black holes in AdS5

We construct the microstates of near-extremal black holes in AdS_5 x S5 as gases of defects distributed in heavy BPS operators in the dual SU(N) Yang-Mills theory. These defects describe open strings on spherical D3-branes in the S5, and we show that they dominate the entropy by directly enumerating them and comparing the results with a partition sum calculation. We display new decoupling limits in which the field theory of the lightest open strings on the D-branes becomes dual to a near-horizo… more

Date: July 24, 2007

Creator: Simon, Joan; Balasubramanian, Vijay; de Boer, Jan; Jejjala, Vishnu & Simon, Joan

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A Unified Monte Carlo Approach to Fast Neutron Cross Section Data Evaluation.

A unified Monte Carlo (UMC) approach to fast neutron cross section data evaluation that incorporates both model-calculated and experimental information is described. The method is based on applications of Bayes Theorem and the Principle of Maximum Entropy as well as on fundamental definitions from probability theory. This report describes the formalism, discusses various practical considerations, and examines a few numerical examples in some detail.

Date: March 3, 2008

Creator: Smith, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Quantum entanglement of baby universes

We study quantum entanglements of baby universes which appear in non-perturbative corrections to the OSV formula for the entropy of extremal black holes in type IIA string theory compactified on the local Calabi-Yau manifold defined as a rank 2 vector bundle over an arbitrary genus G Riemann surface. This generalizes the result for G=1 in hep-th/0504221. Non-perturbative terms can be organized into a sum over contributions from baby universes, and the total wave-function is their coherent super… more

Date: December 7, 2006

Creator: Essman, Eric P.; Aganagic, Mina; Okuda, Takuya & Ooguri, Hirosi

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Precision cosmology and the landscape

After reviewing the cosmological constant problem -- why is Lambda not huge? -- I outline the two basic approaches that had emerged by the late 1980s, and note that each made a clear prediction. Precision cosmological experiments now indicate that the cosmological constant is nonzero. This result strongly favors the environmental approach, in which vacuum energy can vary discretely among widely separated regions in the universe. The need to explain this variation from first principles constitut… more

Date: October 1, 2006

Creator: Bousso, Raphael & Bousso, Raphael

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

THERMODYNAMIC TABLES FOR NUCLEAR WASTE ISOLATION, V.1: AQUEOUSSOLUTIONS DATABASE

Tables of consistent thermodynamic property values for nuclear waste isolation are given. The tables include critically assessed values for Gibbs energy of formation. enthalpy of formation, entropy and heat capacity for minerals; solids; aqueous ions; ion pairs and complex ions of selected actinide and fission decay products at 25{sup o}C and zero ionic strength. These intrinsic data are used to calculate equilibrium constants and standard potentials which are compared with typical experimental… more

Date: May 1, 1988

Creator: Phillips, S.L.; Hale, F.V. & Silvester, L.F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Onset of Convection in Two Liquid Layers with Phase Change

We perform linear stability calculations for horizontal fluid bilayers that can undergo a phase transformation, taking into account both buoyancy effects and thermocapillary effects in the presence of a vertical temperature gradient. We compare the familiar case of the stability of two immiscible fluids in a bilayer geometry with the less-studied case that the two fluids represent different phases of a single-component material, e.g., the water-steam system. The two cases differ in their interf… more

Date: September 14, 2006

Creator: McFadden, G B; Coriell, S R; Gurski, K F & Cotrell, D L

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

THERMODYNAMICS OF LIGHT EMISSION AND FREE-ENERGY STORAGE INPHOTOSYNTHESIS

A Planck law relationship between absorption and emission spectra is used to compute the fluorescence spectra of some photosynthetic systems from their absorption spectra. Calculated luminescence spectra of purple bacteria agree well but not perfectly with published experimental spectra. Application of the Planck law relation to published activation spectra for Systems I and II of spinach chloroplast permits independent calculation of the luminescence spectra of the two systems; if the luminesc… more

Date: April 1, 1967

Creator: Ross, Robert T. & Calvin, Melvin

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Active Creation of Instrinsically Localized Vibrations in Uranium Using X-Ray and Neutron Scattering

In real materials, nonlinear forces cause the frequencies of vibrating atoms to depend on amplitude. As a consequence, a large-amplitude fluctuation on the scale of the atom spacing can develop a frequency that does not resonate with the normal modes, causing energy to become trapped in an intrinsically localized mode (ILM)--also called 'discrete breather' or 'lattice soliton'. As temperature is increased, entropy is expected to stabilize increased concentrations of these random hotspots. This … more

Date: August 23, 2007

Creator: Manley, M.; Alatas, A.; Trouw, F.; Hults, W.; Leu, B.; Lynn, J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dynamical tests on fiber optic data taken from the riser section of a circulating fluidized bed

Dynamical tests have been applied to fiber optic data taken from a cold-flow circulating fluidized bed to characterize flow conditions, identify three time and/or length scales (macro, meso, and micro), and understand the contribution these scales have on the raw data. The characteristic variable analyzed is the raw voltage signal obtained from a fiber-optic probe taken at various axial and radial positions under different loading conditions so that different flow regimes could be attained. The… more

Date: November 1, 2007

Creator: Taylor, E. M.; Guenther, C. P. & Breault, R. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

FOURIER ANALYSIS OF EXTENDED FINE STRUCTURE WITH AUTOREGRESSIVE PREDICTION

Autoregressive prediction is adapted to double the resolution of Angle-Resolved Photoemission Extended Fine Structure (ARPEFS) Fourier transforms. Even with the optimal taper (weighting function), the commonly used taper-and-transform Fourier method has limited resolution: it assumes the signal is zero beyond the limits of the measurement. By seeking the Fourier spectrum of an infinite extent oscillation consistent with the measurements but otherwise having maximum entropy, the errors caused by… more

Date: January 1, 1985

Creator: Barton, J. & Shirley, D.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

ISOLEUCYL-tRNA SYNTHETASE OF E. coli B. A RAPID KINETIC INVESTIGATION OF THE L-ISOLEUCINE ACTIVATING REACTION

We have investigated the preequilibrium kinetics of the L-isoleucine activation reaction catalyzed by Ile-tRNA synthetase in the presence of a fluorescent reporter group, 2-p-toluidinylnaphthalene-6-sulfonate, using the stopped-flow technique. It is found that of all the reactants involved, L-isoleucine binds slowest to the enzyme, apparently in a two-step process. The kinetics of the reaction are invariant in the presence of co-reactants, whereas the kinetics for ATP are drastically changed in… more

Date: May 1, 1972

Creator: Holler, E. & Calvin, Melvin

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Extension of 4-8 Texture Hierarchies to Large Video Processing and Visualization

The purpose of this Techbase was to reduce to practice the tiled 4-8 texture hierarchy for the display of video imagery (i.e. sequences of frames). The immediate intent was to demonstrate its use in the analysis and display of sensor imagery. As sensors are increasing in resolution the physical amount of imagery that needs to be displayed can quickly overwhelm most display systems. For example, a sensor with a horizontal resolution of over 8000 pixels would generate an image over 10 feet wide o… more

Date: November 30, 2007

Creator: Senecal, J G & Wegner, A E

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Linearized semiclassical initial value time correlation functions with maximum entropy analytic continuation

The maximum entropy analytic continuation (MEAC) method is used to extend the range of accuracy of the linearized semiclassical initial value representation (LSC-IVR)/classical Wigner approximation for real time correlation functions. The LSC-IVR provides a very effective 'prior' for the MEAC procedure since it is very good for short times, exact for all time and temperature for harmonic potentials (even for correlation functions of nonlinear operators), and becomes exact in the classical high … more

Date: August 1, 2008

Creator: Liu, Jian & Miller, William H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Temporal Entropy Generation in the Viscous Layers of Laterally-converging Duct Flows

Since insight into entropy generation is a key to increasing efficiency and thereby reducing fuel consumption and/or waste and -- for wall-bounded flows -- most entropy is generated in the viscous layer, we examine the transient behavior of its dominant contributor there for a non-canonical flow. New measurements in oil flow are presented for the effects of favorable streamwise mean pressure gradients on temporal entropy generation rates and, in the process, on key Reynolds-stress-producing eve… more

Date: December 1, 2008

Creator: McEligot, Donald M.; Brodkey, Robert S. & Eckelmann, Helmut

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Quantum geometry and gravitational entropy

Most quantum states have wavefunctions that are widely spread over the accessible Hilbert space and hence do not have a good description in terms of a single classical geometry. In order to understand when geometric descriptions are possible, we exploit the AdS/CFT correspondence in the half-BPS sector of asymptotically AdS_5 x S5 universes. In this sector we devise a"coarse-grained metric operator" whose eigenstates are well described by a single spacetime topology and geometry. We s… more

Date: May 29, 2007

Creator: Simon, Joan; Balasubramanian, Vijay; Czech, Bart Iomiej; Larjo, Klaus; Marolf, Donald & Simon, Joan

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Improving Estimation Accuracy of Aggregate Queries on Data Cubes

In this paper, we investigate the problem of estimation of a target database from summary databases derived from a base data cube. We show that such estimates can be derived by choosing a primary database which uses a proxy database to estimate the results. This technique is common in statistics, but an important issue we are addressing is the accuracy of these estimates. Specifically, given multiple primary and multiple proxy databases, that share the same summary measure, the problem is how t… more

Date: August 15, 2008

Creator: Pourabbas, Elaheh & Shoshani, Arie

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

HIGH RESOLUTION FOURIER ANALYSIS WITH AUTO-REGRESSIVE LINEAR PREDICTION

Auto-regressive linear prediction is adapted to double the resolution of Angle-Resolved Photoemission Extended Fine Structure (ARPEFS) Fourier transforms. Even with the optimal taper (weighting function), the commonly used taper-and-transform Fourier method has limited resolution: it assumes the signal is zero beyond the limits of the measurement. By seeking the Fourier spectrum of an infinite extent oscillation consistent with the measurements but otherwise having maximum entropy, the errors c… more

Date: April 1, 1984

Creator: Barton, J. & Shirley, D.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Physics of reshock and mixing in single-mode Richtmyer-Meshkov instability

The ninth-order weighted essentially non-oscillatory (WENO) shock-capturing method is used to investigate the physics of reshock and mixing in two-dimensional single-mode Richtmyer-Meshkov instability to late times. The initial conditions and computational domain were adapted from the Mach 1.21 air(acetone)/SF{sub 6} shock tube experiment of Collins and Jacobs [J. Fluid Mech. 464, 113 (2002)]: the growth of the bubble and spike perturbation amplitudes from fifth- and ninth-order WENO simulation… more

Date: December 13, 2006

Creator: Schilling, O; Latini, M & Don, W

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Universal Entanglement Entropy in 2D Conformal Quantum Critical Points

We study the scaling behavior of the entanglement entropy of two dimensional conformal quantum critical systems, i.e. systems with scale invariant wave functions. They include two-dimensional generalized quantum dimer models on bipartite lattices and quantum loop models, as well as the quantum Lifshitz model and related gauge theories. We show that, under quite general conditions, the entanglement entropy of a large and simply connected sub-system of an infinite system with a smooth boundary ha… more

Date: December 5, 2008

Creator: Hsu, Benjamin; Mulligan, Michael; Fradkin, Eduardo & Kim, Eun-Ah

Item Type: Article

Partner: UNT Libraries Government Documents Department