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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Gravitational collapse and formation of black holes in the Brans-Dicke theory of gravity with (2+1) dimensions

Wu, Rui. Anzhong, Wang. January 2007 (has links)
Thesis (M.S.)--Baylor University, 2007. / Includes bibliographical references (p. 40-41).
32

A new look at the Ashtekar-Magnon energy condition /

Fischer, James P. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 1999. / Typescript (photocopy). Includes bibliographical references (leaves 60-61). Also available on the World Wide Web.
33

Scalar, electromagnetic and elastic waves in periodic and certain broken-periodicity media /

Chakraborty, Sankar. January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 64-68). Also available on the Internet.
34

Scalar, electromagnetic and elastic waves in periodic and certain broken-periodicity media

Chakraborty, Sankar. January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 64-68). Also available on the Internet.
35

The small-scale structure of passive scalar mixing in turbulent boundary layers

Dasi, Lakshmi P. January 2004 (has links)
Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2006. / Cvitanovic, Predrag, Committee Member ; Roberts, Phillip, Committee Member ; Sturm, Terry, Committee Member ; Webster, Donald, Committee Chair ; Yeung, Pui-Kuen, Committee Member.
36

Momentum and scalar transport in the straight pipe and rotating cylinder : a comparison of transport mechanisms /

Bilson, Matthew James. January 2004 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2004. / Includes bibliography.
37

Scalar fields in cosmology

Kujat, Jens, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 93-98).
38

Scalar field theories of nucleon interactions

Dick, Frank Albert. January 2007 (has links)
Dissertation (Ph.D.) -- Worcester Polytechnic Institute. / Keywords: ladder approximation; inelastic process; Bethe-Salpeter; BSE; nucleon; scalar field; pion. Includes bibliographical references (p.161-163).
39

Equações de movimento de uma partícula interagindo com um campo escalar / Equations of motion and particle and scaling field

Nelson Katsuyuki Sato 05 July 1984 (has links)
As equações de movimento de uma partícula (nucleon) interagindo com um campo escalar (mesônico) são obtidas pelo método dos momentos do tensor energia-momentum, de Papapetrou. Depois de um estudo detalhado do campo de radiação mesônico estabelecemos a expressão da força de reação de radiação do campo sobre a partícula. / The equations of motion of a particle (nucleon) interacting with a scalar (mesonic) field are derived by the energy-momentum tensor moments method of Papapetrou. After a detailed study of the mesonic radiation field we establish an expression of the reactive radiation force on the field upon the particle.
40

Dissipative effects in the Early Universe

Metcalf, Thomas Patrick January 2015 (has links)
Inflationary cosmology is the leading candidate for explaining the homogeneity, isotropy and spatial flatness of the universe whilst also providing the mechanism for the seeding of large scale structure. The central theme of inflationary dynamics involves the evolution of a scalar field, called the inflaton, such that its potential drives an accelerated expansion. Warm inflation is the dynamical realization in which interactions between the inflaton and other fields can lead to dissipation of inflaton energy to other dynamical degrees of freedom. Heavy fields coupled to the inflaton mediate the transfer of inflaton energy to light degrees of freedom which thermalize and heat the universe. This damps the inflaton’s motion and allows for the potential formation of a thermal bath during the inflationary period. Hybrid inflation models are a natural way in which warm inflation can be realized, with dissipation of inflaton energy mediated by the waterfall fields to fields in the light sector. In this thesis I outline the dynamics and observational predictions of supersymmetric hybrid inflation driven by radiative corrections in the warm regime. As in the standard cold inflationary scenario inflation ends when the effective mass squared of the waterfall field becomes negative, with the tachyonic instability driving the system to a global minimum in a process called the waterfall transition. I present the effect of including thermal mass corrections to the waterfall fields, and SUSY mass splittings on the quantum effective potential and the resulting dissipation coefficient. I show that including dissipative effects can significantly prolong the inflationary period to produce 50-60 e-folds of inflation with an observationally consistent primordial spectrum. Inflation still requires a microphysical description within a fundamental theory of quantum gravity. This has prompted the search for inflaton candidates within the superabundance of scalar fields present in string theory compactifications, with brane-antibrane inflation in particular emerging as a concrete implementation of SUSY hybrid inflation in a UV complete particle physics model. Inflation proceeds in a brane-antibrane system through the movement of a stack of branes towards a stack of antibranes, with the inflaton field being the interbrane distance. Warm inflation can be implemented in a brane-antibrane system with dissipation of inflaton energy mediated by fields corresponding to strings stretched between the brane and antibrane stacks. It has been shown that this dissipation of inflaton energy in warm inflation can greatly alleviate the η-problem in brane-antibrane scenarios. Whilst these strings mediating dissipation have end points fixed on to both the D3 and D3 stacks, the compact nature of the geometry within which the system is constructed allows these strings to have different winding modes. We investigated how strings with increasing winding number can provide an enhancement to the dissipation coefficient, allowing a significant reduction in the number of branes and antibranes in the warm inflation system, whilst also modifying the inflationary dynamics by reducing the speed at which the system evolves. This may go some way to alleviating the η-problem associated with some constructions of brane-antibrane inflation whilst also potentially providing the best way to motivate the large field multiplicities associated with warm inflation models.

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