scholarly journals GHOSTS AND TACHYONS IN THE FIFTH DIMENSION

2008 ◽  
Vol 23 (06) ◽  
pp. 881-893 ◽  
Author(s):  
MAXIM POSPELOV
Keyword(s):  
Model Building ◽  
Gravity Models ◽  
Kinetic Term ◽  
Finite Width ◽  
Four Dimensions ◽  
Gaussian Profile ◽  
Fifth Dimension ◽  
Compact Dimension ◽  
Dimensional Gravity ◽  
Ghost Field

We present several solutions for the five-dimensional gravity models in the presence of bulk ghosts and tachyons to argue that these "troublesome" fields can be a useful model-building tool. The ghost-like signature of the kinetic term for a bulk scalar creates a minimum in the scale factor, removing the necessity for a negative tension brane in models with the compactified fifth dimension. It is shown that the model with the positive tension branes and a ghost field in the bulk leads to the radion stabilization. The bulk scalar with the variable sign kinetic term can be used to model both positive and negative tension branes of a finite width in the compact dimension. Finally, we present several ghost and tachyon field configurations in the bulk that lead to the localization of gravity in four dimensions, including one solution with the Gaussian profile for the metric, gμν(y) = ημν exp {-αy2}, which leads to a stronger localization of gravity than the Randall–Sundrum model.

Measuring Utilization of ERP Systems Usage in SMEs

2013 ◽  
pp. 22-34
Author(s):  
Hedman Jonas ◽  
Johansson Björn
Keyword(s):  
Enterprise Resource Planning ◽  
Model Building ◽  
Critical Mass ◽  
Resource Planning ◽  
Erp Systems ◽  
Planning Systems ◽  
Four Dimensions ◽  
Factors Influencing ◽  
Enterprise Resource Planning Systems ◽  
The Many

Since deployment of Enterprise Systems (ES) such as Enterprise Resource Planning systems (ERPs) within enterprises, both Large Enterprises (LEs) as well as Small and Medium-sized Enterprises (SMEs) have increased and continue to increase, making it increasingly desirable to measure the degree of utilization of ERP systems in enterprises. One reason for this interest is that no benefits are realized if the systems are not used; since ERPs are massive investments, they need to show benefits, or at least be able to measure the benefits. However, to be able to do so, there is a need to explain ERP systems utilization and the factors that influence ERP utilization. This chapter provides an explanation of factors influencing ERP systems utilization by testing a research model building on four dimensions: volume, breadth, diversity, and depth. The contributions of the research are: First, it provides support for the notion of diffusion found in the theory of network externalities where a critical mass is necessary to achieve benefits. This can be used to better understand failures in ERP projects. Second, the use of volume, breadth and depth provide insights for use as a construct and the need to treat it more rigorously. Third, the study contributes to our understanding of the many aspects of use of IT, such as ERPs, and potentially contributes to value and firm performance from ERP utilization.

scholarly journals APSIS: AN ARTIFICIAL PLANETARY SYSTEM IN SPACE TO PROBE EXTRA-DIMENSIONAL GRAVITY AND MOND

2008 ◽  
Vol 17 (03n04) ◽  
pp. 453-466 ◽  
Author(s):  
VARUN SAHNI ◽  
YURI SHTANOV
Keyword(s):  
Planetary System ◽  
Free Fall ◽  
Experimental Conditions ◽  
Spacecraft Design ◽  
Fifth Dimension ◽  
The Earth ◽  
Perihelion Shift ◽  
Dimensional Gravity ◽  
Free Environment ◽  
Sources Of Contamination

A proposal is made to test Newton's inverse-square law using the perihelion shift of test masses (planets) in free fall within a spacecraft located at the Earth–Sun L2 point. Such an artificial planetary system in space (APSIS) will operate in a drag-free environment with controlled experimental conditions and minimal interference from terrestrial sources of contamination. We demonstrate that such a space experiment can probe the presence of a "hidden" fifth dimension on the scale of a micron, if the periapsis shift of a "planet" can be measured to sub-arc-second accuracy. Some suggestions for spacecraft design are made.

scholarly journals Two Lectures on the Jones Polynomial and Khovanov Homology

2017 ◽  
Author(s):  
Edward Witten
Keyword(s):  
Gauge Theory ◽  
Three Dimensional ◽  
Jones Polynomial ◽  
Khovanov Homology ◽  
Theory Approach ◽  
Laurent Polynomials ◽  
Four Dimensions ◽  
Knot Invariants ◽  
Fifth Dimension ◽  
Instanton Number

In the first of these two lectures I describe a gauge theory approach to understanding quantum knot invariants as Laurent polynomials in a complex variable q. The two main steps are to reinterpret three-dimensional Chern-Simons gauge theory in four dimensional terms and then to apply electric-magnetic duality. The variable q is associated to instanton number in the dual description in four dimensions. In the second lecture, I describe how Khovanov homology can emerge upon adding a fifth dimension.

Nonresponse and Urban Travel Models

1996 ◽  
Vol 1551 (1) ◽  
pp. 82-87
Author(s):  
Piyushimita (Vonu) Thakuriah ◽  
Ashish Sen ◽  
Siim Sööt ◽  
Ed J. Christopher
Keyword(s):  
Large Scale ◽  
Model Building ◽  
Travel Demand ◽  
Gravity Models ◽  
Parameter Estimates ◽  
Trip Generation ◽  
Urban Travel ◽  
Mode Split ◽  
Demand Models ◽  
Simulation Results

Considerable attention has been paid to the presence of nonresponse in large-scale travel surveys on the basis of which urban travel demand models are developed. It has been shown that the effect of nonresponse can be reduced by careful model building, with categorical trip generation models as an example. The same philosophy is extended to logit mode split models and exponential gravity models to show that the usual levels of nonresponse that one encounters in urban travel surveys have virtually no adverse effects on the parameter estimates of these models if the model has been specified correctly. Some simulation results are also presented to show the behavior of logit and exponential gravity model parameter estimates under conditions on nonresponse.

Measuring Utilization of ERP Systems Usage in SMEs

2013 ◽  
pp. 1677-1689
Author(s):  
Hedman Jonas ◽  
Johansson Björn
Keyword(s):  
Enterprise Resource Planning ◽  
Model Building ◽  
Critical Mass ◽  
Resource Planning ◽  
Erp Systems ◽  
Planning Systems ◽  
Four Dimensions ◽  
Factors Influencing ◽  
Enterprise Resource Planning Systems ◽  
The Many

Since deployment of Enterprise Systems (ES) such as Enterprise Resource Planning systems (ERPs) within enterprises, both Large Enterprises (LEs) as well as Small and Medium-sized Enterprises (SMEs) have increased and continue to increase, making it increasingly desirable to measure the degree of utilization of ERP systems in enterprises. One reason for this interest is that no benefits are realized if the systems are not used; since ERPs are massive investments, they need to show benefits, or at least be able to measure the benefits. However, to be able to do so, there is a need to explain ERP systems utilization and the factors that influence ERP utilization. This chapter provides an explanation of factors influencing ERP systems utilization by testing a research model building on four dimensions: volume, breadth, diversity, and depth. The contributions of the research are: First, it provides support for the notion of diffusion found in the theory of network externalities where a critical mass is necessary to achieve benefits. This can be used to better understand failures in ERP projects. Second, the use of volume, breadth and depth provide insights for use as a construct and the need to treat it more rigorously. Third, the study contributes to our understanding of the many aspects of use of IT, such as ERPs, and potentially contributes to value and firm performance from ERP utilization.

scholarly journals Fat brane, dark matter and localized kinetic terms in six dimensions

2020 ◽  
Vol 80 (2) ◽  
Author(s):  
Ricardo G. Landim
Keyword(s):  
Dark Matter ◽  
Particle Physics ◽  
Direct Detection ◽  
Kinetic Term ◽  
Finite Width ◽  
Complex Scalar ◽  
Abelian Gauge ◽  
Complex Scalar Field ◽  
Relic Abundance

Abstract Extra dimensions (ED) have been used as attempts to explain several phenomena in particle physics over the years. In this paper we investigate the role of an abelian gauge field as mediator of the interaction between dark matter (DM) and Standard Model (SM) particles, in a model with two flat and transverse ED compactified on the chiral square. DM is confined in a thin brane, localized at the origin of the chiral square, while the SM is localized in a finite width brane, lying in the opposite corner of the square. A brane-localized kinetic term is present in the DM brane, while in the fat brane it is not allowed. In this model the kinetic mixing is not required because we assume that the SM particles couple to the mediator through their $$B-L$$B-L charges, while DM couples to it via a dark charge. Assuming a complex scalar field as DM candidate it is possible to obtain the observed DM relic abundance and avoid direct detection constraints for some parameter choices.

scholarly journals Food security, where is thy fifth dimension? A comparative analysis of the four dimensions food security framework from the lens of West African smallholder farmers

2021 ◽  
Author(s):  
Niagia Santuah ◽  
Joseph Abazaami
Keyword(s):  
Food Security ◽  
Smallholder Farmers ◽  
Field Research ◽  
Quantitative Information ◽  
Study Data ◽  
Northern Ghana ◽  
Security Framework ◽  
Four Dimensions ◽  
Fifth Dimension ◽  
Indigenous Methodologies

This study consists of a comprehensive literature review and a qualitative field research to gather empirical data through key informant interviews and focus groups. Using both scientific and indigenous methodologies the study assessed the suitability of the FAO inspired four dimensions food security framework smallholder farmers in Kasem-speaking people in contiguous communities between northern Ghana and southern Burkina Faso. Indigenous methodologies included gathering of wise sayings, proverbs, poems, songs, and riddles. The use of indigenous methodologies was justified because the analysis of Kasem proverbs, expressions and songs give insights into the deeper meanings of cultural concepts and images, which inform their daily practices (Cassiman, 2006). Appreciative Inquiry technique of data collection was used, as it builds on the strengths of the existing system and also emphasizes the practical use of the results of research (Wilson, 2008). Scientific methodologies are inadequate for accessing knowledge in the metaphysical realm which is a key aspect of the worldview of indigenous people. Privacy of participants and confidentiality of information was protected throughout the research. To further protect the confidentiality and also obviate the need for documentation of names of study participants, the study opted for verbal informed consent and assent instead of written. Verbal consent was obtained from participants before interviews were conducted. Identification numbers were assigned to transcripts for organizational purposes only; to indicate the data source category and date. Any potential research participants who chose not to participate, or withdrew their participation during the interview, were cordially thanked for their time and excused. Though a purely qualitative study, data were analysed quantitatively to generate graphs and tables to assess the distribution of opinion on key variables while verbatim quotations were used to support the quantitative information.

Virtual Laboratories: Comparability of Real and Virtual Environments for Environmental Psychology

2003 ◽  
Vol 12 (4) ◽  
pp. 360-373 ◽  
Author(s):  
Yvonne A. W. de Kort ◽  
Wijnand A. IJsselsteijn ◽  
Jolien Kooijman ◽  
Yvon Schuurmans
Keyword(s):  
Virtual Environments ◽  
Cognitive Mapping ◽  
Environmental Psychology ◽  
Four Dimensions ◽  
Fifth Dimension ◽  
Simulated Environment ◽  
Virtual Laboratories ◽  
Research Findings ◽  
New Research ◽  
And Behavior

Virtual environments have the potential to become important new research tools in environment behavior research. They could even become the future (virtual) laboratories, if reactions of people to virtual environments are similar to those in real environments. The present study is an exploration of the comparability of research findings in real and virtual environments. In the study, 101 participants explored an identical space, either in reality or in a computer-simulated environment. Additionally, the presence of plants in the space was manipulated, resulting in a 2 (environment)× 2 (plants) between-subjects design. Employing a broad set of measurements, we found mixed results. Performances on size estimations and a cognitive mapping task were significantly better in the real environment. Factor analyses of bipolar adjectives indicated that, although four dimensions were similar for both environments, a fifth dimension of environmental assessment—termedarousal—was absent in the virtual environment. In addition, we found significant differences on the scores of four of the scales. However, no significant interactions appeared between environment and plants. Experience of and behavior in virtual environments have similarities to that in real environments, but there are important differences as well. We conclude that this is not only a necessary, but also a very interesting research subject for environmental psychology.

scholarly journals FIELD CONFIGURATIONS AND THEIR INSTABILITY INDUCED BY HIGHER DIMENSIONS OF SPACE–TIME: AN EXAMPLE

1999 ◽  
Vol 14 (34) ◽  
pp. 2393-2401 ◽  
Author(s):  
LAURA MERSINI
Keyword(s):  
Higher Dimensions ◽  
Energy Difference ◽  
Field Configuration ◽  
The Other ◽  
Four Dimensions ◽  
Fifth Dimension ◽  
True Vacuum ◽  
Twisted Field ◽  
Five Dimensional Model ◽  
The Stability

We use the model of L. Randall et al.3 to investigate the stability of allowed quantum field configurations. Firstly, we find that due to the topology of this five-dimensional model, there are two possible configurations of the scalar field, untwisted and twisted. They give rise to two types of instability. Secondly, when allowed to interact in the brane, the untwisted field is shown to be unstable even if it is at the true vacuum ground state as a result of one-loop corrections that arise from coupling with the twisted field. On the other hand, the twisted field can make the two three-branes (that are otherwise identical in their properties and geometry) distinguishable therefore causing an energy difference between them. That is due to the antiperiodicity of the twisted fields, when rotating with π to go from one three-brane to the other. This energy difference between the branes renders the fifth dimension unstable. This toy model is simple enough to use to illustrate a point that can be important for the general case of any high dimension model, namely: higher dimensions, besides many other effects can also induce more than one field configuration and that can have consequences (e.g. instabilities) even after reducing the problem to four dimensions.

Structural cross sections based on a gravity survey of parts of the Quetico and Wawa subprovinces near Thunder Bay, Ontario

1990 ◽  
Vol 27 (2) ◽  
pp. 187-199 ◽  
Author(s):  
M. M. Kehlenbeck ◽  
S. P. Cheadle
Keyword(s):  
Cross Sections ◽  
Gravity Data ◽  
Bouguer Anomaly ◽  
Gravity Models ◽  
Low Grade ◽  
Thunder Bay ◽  
Metavolcanic Rocks ◽  
Dimensional Gravity ◽  
Anomaly Map ◽  
Bouguer Anomaly Map

In this study, gravity data from 350 new gravity stations are combined with those from 50 previously surveyed stations in a detailed Bouguer anomaly map of a portion of the Quetico and Wawa subprovinces north and west of Thunder Bay, Ontario.In general, high gravity values characterize the southern and southwestern part of the area where metavolcanic rocks of the Wawa subprovince dominate. Much of the Quetico subprovince forms a broad gravitational low, reflecting extensive exposures of gneisses, schists, and migmatites. Well-defined gravity lows are associated with several granitic intrusive bodies.Three- and [Formula: see text]-dimensional gravity models of subsurface configuration of the density contrasts, representative of major rock units, indicate a trough-like structure for the metavolcanic rocks of the Wawa subprovince. This trough-like structure is flanked by a domical feature in the granitoid rocks to the south. North of the metavolcanic rocks, a succession of low-grade greywackes and slates occupies a basinal structure. These structures form the principal subsurface elements of the Wawa subprovince in this area.The gneisses, schists, and migmatites of the Quetico subprovince form a thick, southward-dipping, wedge-shaped structure that may extend under the structures of the Wawa subprovince. This wedge-shaped structure is underlain by a model unit of greater density representative of mafic gneisses and amphibolites. The denser substratum is modelled with local abrupt changes in dip corresponding in position with the Quetico and Hawkeye Lake faults.

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