Showing papers by "University of Wisconsin–Milwaukee published in 1974"
TL;DR: In this paper, the authors proposed a method for defining finite expectation values of the energy-momentum tensor of a quantized scalar field interacting with the classical Einstein gravitational field when the mass of the scalar matter field does not vanish.
Abstract: In the theory of a quantized scalar field interacting with the classical Einstein gravitational field, the formal expression for the energy-momentum tensor has infinite expectation values. We propose a procedure for defining, in certain cosmological models, suitable finite expectation values of this tensor, when the mass of the scalar matter field does not vanish. Our method uses the decomposition of the scalar field into modes permitted by the symmetry of the models. The identification of the divergent terms, which are to be subtracted mode by mode from the formal tensor, follows in a natural manner from the identification of physically relevant creation and annihilation operators under conditions of arbitrarily slow (adiabatic) time dependence of the metric. The extension of the results to periods of strong time dependence is accomplished with the aid of the requirement that the four-divergence of the regularized energy-momentum tensor remain zero at all times. The energy-momentum tensor obtained by adiabatic regularization is the same as that obtained by the $n$-wave regularization procedure of Zel'dovich and Starobinsky, although the two methods are conceptually quite different. In this paper we apply the adiabatic-regularization method to the minimally coupled scalar field with positive mass in the Robertson-Walker universes. Later papers will concern extensions to conformal coupling, anisotropic metrics, and massless fields, as well as a possible physical interpretation of the regularization procedure in terms of renormalization of coupling constants in Einstein's equation.
394 citations
TL;DR: In this paper, the authors studied the physical energy-momentum tensor through which the geometry of spacetime is influenced by a quantized scalar field with conformal coupling to the metric.
Abstract: In preparation for an investigation of whether field-theoretic effects helped to make the early universe become isotropic, we seek to determine the physical (divergence-free) energy-momentum tensor through which the geometry of spacetime is influenced by a quantized scalar field with conformal ("new improved") coupling to the metric. The cosmological models studied are the Kasner-like (type I) metrics (homogeneous, spatially flat, nonrotating, but anisotropic), and also the isotropic Robertson-Walker metrics. The methods employed have previously been expounded in the context of a minimally coupled scalar field and a Robertson-Walker metric. Three divergent leading terms are extracted from an adiabatic expansion of the formal expressions for the expectation values of the energy density and pressures. In the Kasner case a slight reshuffling of the leading terms in the energy density displays all divergences to be proportional to either the metric tensor or a second-order curvature tensor which vanishes when the spacetime is isotropic; hence a finite energy-momentum tensor remains after renormalization of the cosmological constant and one other coupling constant in a generalized Einstein equation. In the Robertson-Walker cases, because of conformal flatness, there is no divergence beyond the usual quartically divergent constant vacuum energy; when the mass is not zero, however, a finite renormalization of the gravitational constant is suggested. The correctness of the methods is tested by considering a coordinate system in which flat spacetime assumes the form of a Kasner universe: The adiabatic definition of particle number and vacuum, which is basic to our expansion and renormalization methods, is seen to be consistent with the usual flat-space concepts.
250 citations
TL;DR: Two species of forest birds, the least flycatcher and the red-eyed vireo, when breeding in the same season in the the same habitat, adjust their temporal pattern of singing to avoid the overlapping of songs.
Abstract: Two species of forest birds, the least flycatcher and the red-eyed vireo, when breeding in the same season in the same habitat, adjust their temporal pattern of singing to avoid the overlapping of songs. The avoidance of acoustic interference is more marked in the flycatcher, which has a briefer song than the vireo.
195 citations
TL;DR: In this paper, the authors demonstrate the possibility of removing the divergences in the energy-momentum tensor by identifying divergent terms with renormalizations of the coupling constants in the gravitational field equation, modified to include a cosmological term and terms quadratic in the curvature.
175 citations
TL;DR: In this article, a review article on the boson method in superconductivity is presented, which covers derivations of the basic equations and applications of these equations to the magnetic properties of type II superconductors and to the Josephson phenomena.
156 citations
TL;DR: The authors showed that when one or more speech sounds in a sentence are replaced by a noise meeting certain criteria, the listener mislocalizes the extraneous sound and believes he hears the missing phoneme(s) clearly.
Abstract: Earlier experiments have shown that when one or more speech sounds in a sentence are replaced by a noise meeting certain criteria, the listener mislocalizes the extraneous sound and believes he hears the missing phoneme(s) clearly The present study confirms and extends these earlier reports of phonemic restorations under a variety of novel conditions All stimuli had some of the context necessary for the appropriate phonemic restoration following the missing sound, and all sentences had the missing phoneme deliberately mispronounced before electronic deletion (so that the neighboring phonemes could not provide acoustic cues to aid phonemic restorations) The results are interpreted in terms of mechanisms normally aiding veridical perception of speech and nonspeech sounds
134 citations
111 citations
TL;DR: This article showed that under appropriate conditions subjects can be trained to distinguish between and to identify permuted orders within sequences of nonrelated sounds each lasting only 10 msec or less, and that much of what passes for direct identification of order is actually based on prior identification of a larger pattern.
95 citations
TL;DR: In this paper, the effect of electron beam monitored gas adsorption on the clean Si surface was studied using Auger electron spectroscopy, and it was shown that the beam affects the AES adsorptive signal of CO and O2 on Si by dissociating the adsorbed molecules on the surface and subsequently promoting diffusion of atomic oxygen into the bulk.
88 citations
TL;DR: The formation and reactivity of O2− on a Vycor quartz supported silver catalyst has been investigated by electron paramagnetic resonance spectroscopy (EPR) in this article.
86 citations
TL;DR: In this paper, the spectral properties of the reduced molybdoantimonylphosphoric acid were used to determine the optimal formation conditions and stoichiometry of reduced heteropoly acid, and it was found that a [H+]/[MoO2-4] ratio of 70± 10 was optimal for formation between 0.0008 and 0.01 M molybenum.
TL;DR: In this paper, the efficacy of behavioral treatment of obesity is divided into self and experimenter managed categories and reviewed with respect to outcome and adequacy of design, and suggestions for research are offered.
01 Jan 1974
TL;DR: The issues which separate the members of this symposium concern the nature of reduction and scientific theories, and these issues involve primarily informal aspects of theory reduction as mentioned in this paper. But more than this, they concern the philosophy of science itself.
Abstract: The issues which separate the members of this symposium concern the nature of reduction and scientific theories. However, these issues involve primarily informal aspects of theory reduction. But more than this, they concern the nature of philosophy of science itself.
TL;DR: The stability and asymptotic behavior of solutions of an autonomous linear differential system x' =,4x are determined by the spectrum of the constant matrix A as discussed by the authors, which is the limiting system X' = Ax.
TL;DR: In this paper, an explicit topological formulation of the Lagrangian and the Hamiltonian equations for a large class of nonlinear networks is given for networks containing both linear and nonlinear controlled sources.
Abstract: This paper presents an explicit topological formulation of the Lagrangian and the Hamiltonian equations for a large class of nonlinear networks. In particular, formulations are given for networks containing both linear and nonlinear controlled sources. Classically, the Lagrangian and Hamiltonian equations are derived from variational techniques; in this paper topological techniques are used for the formulation.
TL;DR: In this paper, separate groups of 30 unpracticed Ss were required to determine whether repeated sequences, each consisting of reiterated presentations of the same three or four successive items, were in identical or permuted order.
Abstract: Earlier work with unpracticed Ss has indicated that identification (naming) of the temporal order of components within repeated sequences consisting of three or four unrelated sounds cannot be accomplished when the item durations are 200 msec or less. In the present experiment, separate groups of 30 unpracticed Ss were required to teil whether alternated sequences, each consisting of reiterated presentations of the same three or four successive items, were in identical or permuted order. Naming of the order within the sequences was not required. Accuracy of same/different judgments was significantly better than chance when all items lasted 200 msec. Changing the duration of each item in one of the two sequences above or below 200 msec made the task more difficult. These results, together with other evidence, suggest that: (1) identification of order and recognition of auditory temporal patterns may represent fundamentally different processes, and (2) recognition may involve matching of “temporal templates.”
TL;DR: The linear free energy relationships suggest the operation of a steric factor in the kinetics of the reactions described, thereby providing an empirical chemical rationale for these differences in biological activity.
TL;DR: In this paper, a coprecipitation method is described which results in the preparation of the α-phass bismuth molybdate catalyst in high purity and which is reproducible.
TL;DR: In this paper, an exact expression of spin operators in terms of magnons and quasielectrons in ferromagnetism is presented, and its relation to the Holstein-Primakoff expression is discussed.
Abstract: We present an exact expression of spin operators in terms of magnons and quasielectrons in ferromagnetism. Its relation to the Holstein-Primakoff expression is discussed. The result shows that the spin rotation of electrons is induced by a transformation of magnons and quasielectrons which is different from rotation.
TL;DR: In this article, the spontaneous breakdown of symmetry is investigated in the path-integral formalism, where the generating functional is modified by the addition of a limiting "ϵ term" which fixes the direction of the breaking.
TL;DR: In this paper, a sample of 50 New York City neighborhoods in which middle-income housing projects were built, assessed values increased by 9.89% per year while control areas increased only 4.64% annually.
TL;DR: The results are used to assess the importance of ZnKTS in the mechanism of cytot toxicity in vivo and to rationalize the large variation in cytotoxicity observed in vitro with these zinc complexes.
TL;DR: In this article, the spatial and temperature dependence of the magnetization near a surface and near a phase transition is analyzed in terms of an interplay between the correlation length and the extrapolation length.
Abstract: Within mean-field theory, it is possible to analytically calculate the spatial and temperature dependence of the magnetization near a surface and near a phase transition. These algebraic forms are then used in the Landau-Ginzburg free energy to obtain the surface specific heat and a relaxation time for the surface spins driven to a weak nonequilibrium. These physical quantities have been found to have a temperature dependence that varies continuously with the change in the surface-plane exchange constant. Such a behavior is interpreted in terms of an interplay between the correlation length $\ensuremath{\xi}$ and the extrapolation length $\ensuremath{\lambda}$ where $\ensuremath{\lambda}$ effectively determines the range of the surface effects.
TL;DR: A factor analysis of television viewing, which avoids conceptual and statistical shortcomings found in previous studies, generated eight configurations that appear to be show types that illustrate the implementation of promotional segmentation strategy.
Abstract: A factor analysis of television viewing, which avoids conceptual and statistical shortcomings found in previous studies, generated eight configurations that appear to be show types. Show type and d...
TL;DR: In this article, the exact solution for the drawdown in and around a well of large diameter in a homogeneous, isotropic leaky aquifer induced by a time-dependent pumping rate is presented.
01 Jul 1974-Metallurgical and Materials Transactions B-process Metallurgy and Materials Processing Science
TL;DR: In this paper, the rate of absorption of carbon from CO-CO2 mixtures into stagnant liquid iron and of unidirectional dissolution of graphite into stag-nant liquid IR and iron-carbon alloys at 1560°C was measured.
Abstract: Measurements have been made of the rate of absorption of carbon from CO-CO2 mixtures into stagnant liquid iron and of the rate of unidirectional dissolution of graphite into stag-nant liquid iron and iron-carbon alloys at 1560°C. Total absorptions and concentration pro-files were found to be consistent with a composition dependent chemical diffusivity given byD = 1.1 (1 + wt pct CJ5.3) X 10∼4 cm2Js with an uncertainty of about ±0.2 x 10-4. It is shown that many of the previous determina-tions of the chemical and self-diffusivity are consistent with this suggested dependence.
TL;DR: In this paper, the optimal allocation of the marketing budget within the marketing-mix decision variables so that sales or profit is maximized in a planning horizon was investigated, and a procedure to estimate a functional of sales on the marketing mix and environmental variables was provided.
Abstract: This paper investigates the optimal allocation of the marketing budget within the marketing-mix decision variables so that sales or profit is maximized in a planning horizon. Since the influence of marketing mix variables upon sales are, in reality, nonlinear and interactive, a geometric programming algorithm is used that solves this problem. A procedure to estimate a functional of sales on the marketing mix and environmental variables utilizing the experienced judgments of the firm's executives and the raw data is provided. The derived functional is later optimized by the Geometric Programming algorithm under a constraint set consisting of budget and strategy restrictions imposed by a firm's marketing environment, and conditions under which the optimal solution is either local or global are identified. An empirical application for a large midwestern brewery is provided which utilizes and illustrates both the estimation an optimization procedures.
01 May 1974
TL;DR: An algorithm is presented to test the graph isomorphism for undirected linear graphs by relabels the nodes of graphs to obtain optimum codes, which are related to invariant features in feature extraction.
Abstract: An algorithm is presented to test the graph isomorphism for undirected linear graphs. The graph isomorphism between two or more graphs can be tested by obtaining their optimum codes. The algorithm relabels the nodes of graphs to obtain optimum codes. The optimum code is the code of maximum weight obtained from the upper triangle of the Adjacency matrix of the given graph. The method of ordering the nodes of a graph to produce a code invariant to isomorphism is related to invariant features in feature extraction [7], [15].
TL;DR: In this paper, the spontaneous breakdown of symmetries in the path-integral framework was studied and a modification of the generating functional was proposed to provide the required flexibility that can lead to different solutions.