37 research outputs found
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The inflation sector of extended inflation
In extended inflation the inflationary era is brought to a close by the process of percolation of true vacuum bubbles produced in a first-order phase transition. In this paper I discuss several effects that might obtain if the Universe undergoes an inflationary first-order phase transition. 17 refs
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The neutron electric dipole moment and the Weinberg mechanism
We gave an overview of various mechanism for CP violation paying special attention to their prediction of the neutron electric dipole moment. The implication of the recent developments associated with the color electric dipole moment of gluon in various models of CP-violation are then critically assessed. 25 refs
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Soft inflation
We study the cosmology resulting from two coupled scalar fields, one which is either a new inflation or chaotic type inflation and the other which has an exponentially decaying potential. Such potential may appear in the conformally transformed frame of generalized Einstien theories like the Jordan-Brans-Dicke theory. The constraints necessary for successful inflation are examined. We find conventional GUT models such as SU(5) are compatible with new inflation, while restrictions on the self-coupling constant are significantly loosened for chaotic inflation. 20 refs., 1 fig
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Gravitational couplings of the inflaton in extended inflation
We discuss a new extended inflationary scenario evading the difficulties of the original model. Our model can thermalize the energy in the bubble walls by the necessary epoch, and establish a Robertson-Walker frame in the bubble clusters. The essential new ingredient in our model is the observation that the coupling of inflaton to the Jordan-Brans-Dicke field is expected to be different from that of visible matter. 13 refs., 1 fig
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Neutrino magnetic moment
We review attempts to achieve a large neutrino magnetic moment ({mu}{sub {nu}} {le} 10{sup {minus}11}{mu}{sub B}), while keeping neutrino light or massless. The application to the solar neutrino puzzle is discussed. 24 refs
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SSC collider dipole magnet end mechanical design
This paper describes the mechanical design of the ends of Superconducting Super Collider dipole magnets to be constructed and tested at Fermilab. Coil end clamps, end yoke configuration, and end plate design are discussed. Loading of the end plate by axial Lorentz forces is discussed. Relevant data from 40 mm and 50 mm aperture model dipole magnets built and tested at Fermilab are presented. In particular, the apparent influence of end clamp design on the quench behavior of model SSC dipoles is described. 8 refs., 3 figs
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Providing a computing environment for a high energy physics workshop
Although computing facilities have been provided at conferences and workshops remote from the host institution for some years, the equipment provided has rarely been capable of providing for much more than simple editing and electronic mail. This report documents the effort involved in providing a local computing facility with world-wide networking capability for a physics workshop so that we and others can benefit from the knowledge gained through the experience
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A new approach to chiral fermions on the lattice
We wish to describe a method for formulating, on the lattice, field theories that contain Dirac particles with chiral couplings to gauge fields. As is well-known, the most straight-forward lattice transcription of the continuum action for a Dirac particle leads to the doubling problem: for every particle of a given chirality in the continuum theory, there appear on the lattice, in d dimensions, 2{sup d} particles, with equal numbers of particles of left- and right-handed chirality. No-go theorems, state that it is impossible to eliminate the doubling problem and still maintain an exact chiral gauge symmetry. Rather than follow an approach that attempts to circumvent the no-go theorems we, instead, explore the possibility of abandoning exact chiral symmetry
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The Age of the Universe: Concordance
Arguments on the Age of the Universe, t{sub u}, are reviewed. The four independent age determination techniques are: dynamics (Hubble Age and deceleration); oldest stars (globular clusters); radioactive dating (nucleocosmochronology); and white dwarf cooling (age of the disk). While discussing all four, this review will concentrate more on nucleocosmochronology due in part to recent possible controversies there. It is shown that all four techniques are in general agreement, which is an independent argument in support of a catastrophic creation event such as the Big Bang. It is shown that the most consistent range of cosmological ages is for 12 {approx lt} t{sub u} {approx lt} 17Gyr. It is argued that the upper bound from white dwarf cooling is only {approximately}10Gyr due to the disk of the Galaxy probably forming several Gyr after the Big Bang itself. Only values of the Hubble constant, H{sub 0} {approx lt} 60km/sec/Mpc, are consistent with the other age arguments if the universe is at its critical density. An interesting exception to this limit is noted for the case of a domain wall dominated universe where ages as large as 2/H{sub 0} are possible. 42 refs., 1 fig., 1 tab
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Ultrahigh-energy particle flux from cosmic strings
We estimate the expected flux of ultrahigh-energy (> 10{sup 18}eV) protons in the present epoch due to a process which involves collapse or multiple self-intersections of a special class of closed cosmic string loops in the universe. We compare this flux with the observed flux of ultrahigh-energy cosmic rays, and discuss the implications. 19 refs., 1 fig