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Li, Hui; Colgate, S.A.; Miller, J.A.

Los Alamos National Lab., NM (United States). Funding organisation: USDOE Assistant Secretary for Human Resources and Administration, Washington, DC (United States)

Los Alamos National Lab., NM (United States). Funding organisation: USDOE Assistant Secretary for Human Resources and Administration, Washington, DC (United States)

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[en] The free energy stored in the stressed magnetic fields in AGN jets could be dissipated via generating turbulent plasma waves. The authors review several key wave-particle resonant interactions and point out the importance of a broad wave spectrum. Under several idealized assumptions, they show that the transit-time damping process can accelerate electrons to TeV energies in an AGN jet environment, and present a preliminary calculation on the evolution of plasma wave, electron, and photon distributions. The authors especially emphasize several open questions on particle acceleration by waves, and argue that a plausible scenario is to energize electrons out of the thermal background via transit-time damping and further accelerate them by the parallel propagating right-handed waves

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1997; 11 p; Conference on relativistic jets in AGNs; Cracow (Poland); 26-30 May 1997; CONF-9705181--; CONTRACT W-7405-ENG-36; Also available from OSTI as DE98000598; NTIS; US Govt. Printing Office Dep

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Dodelson, S.

Fermi National Accelerator Lab., Batavia, IL (United States). Funding organisation: USDOE Office of Energy Research, Washington, DC (United States)

Fermi National Accelerator Lab., Batavia, IL (United States). Funding organisation: USDOE Office of Energy Research, Washington, DC (United States)

AbstractAbstract

[en] Anisotropies in the Cosmic Microwave Background (CMB) contain a wealth of information about the past history of the universe and the present values of cosmological parameters. I online some of the theoretical advances of the last few years. In particular, I emphasize that for a wide class of cosmological models, theorists can accurately calculate the spectrum to better than a percent. The spectrum of anisotropies today is directly related to the pattern of inhomogeneities present at the time of recombination. This recognition leads to a powerful argument that will enable us to distinguish inflationary models from other models of structure formation. If the inflationary models turn out to be correct, the free parameters in these models will be determined to unprecedented accuracy by the upcoming satellite missions

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Feb 1998; 13 p; 18. Texas symposium on relativistic astrophysics; Chicago, IL (United States); 15-20 Dec 1996; CONF-961254--; CONTRACT AC02-76CH03000; ALSO AVAILABLE FROM OSTI AS DE98052132; NTIS; US GOVT. PRINTING OFFICE DEP

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[en] We consider the possibility that higher-curvature corrections could drive inflation after the compactification to four dimensions. Assuming that the low-energy limit of the fundamental theory is eleven-dimensional supergravity to the lowest order, including curvature corrections and taking the descent from eleven dimensions to four via an intermediate five-dimensional theory, as favored by recent considerations of unification at some scale around ∼10

^{16}GeV, we may obtain a simple model of inflation in four dimensions. The effective degrees of freedom are two scalar fields and the metric. The scalars arise as the large five-dimensional modulus and the self-interacting conformal mode of the metric. The effective potential has a local maximum in addition to the more usual minimum. However, the potential is quite flat at the top, and admits topological inflation. We show that the model can resolve cosmological problems and provide a mechanism for structure formation with very little fine tuning. copyright 1999 The American Physical SocietyPrimary Subject

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[en] A new grand unified model containing the known three generations of quark and lepton in which hadrons are regarded as nontopological solitons formed from quarks is presented. According to the model leptons and quarks are the same in essence. The differences between them are caused by spontaneous symmetry breaking. When a quark is located inside a hadron, its properties will be the same as those of a known quark and its mass very small. When a quark is outside hadrons, its properties will be the same as those of a known lepton, its mass very large and it will rapidly decay. Except defining charge Q

_{0}and fermion number F_{0}which are exactly conserved, we also define interior colour, interior charge and interior fermion number approximately conserved inside a hadron. The (L-B) conservation in the known SU(5) model corresponds to the fermion number F_{0}conservation in the present modelPrimary Subject

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[en] A model of a phase-matched parametric amplifier whose Hamiltonian possesses a cubic nonlinearity with respect to the Bose fields is considered. An exact operator solution is found, and on its basis the evolution of the number of photons and of the quantum fluctuations of one of the modes is investigated. Conditions that determine a sub-Poisson nature of the particle-number distribution and squeezing of the quantum fluctuations of the mode quadratures are found. 10 refs

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Cover-to-cover Translation of Teoreticheskaia I Matematicheskaia Fizika (USSR); Translated from Teoreticheskaya i Matematicheskaya Fizika; 98: No. 2, 289-296(Feb 1994).

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[en] It is found that, for large incident wave numbers and weak potentials, the angular range of the validity of the eikonal approximation is dependent upon the sharpness of the edge of the potentials

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[en] A new difference between a monopole and a very long thin solenoid is presented. It is shown that this result is relevant to a recent attempt of Getino et al., aiming to settle a field energy problem of a charge-monopole system. (orig.)

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[en] The scattering of a scalar particle in an external gravitational field and corrections to the scattering of two scalars due to an external gravitational field in λφ

^{4}theory is considered. It is shown that for the scattering of a scalar in an external gravity, the cross section can rise with energy if the anomalous dimension associated with mass γ_{m}(λ^{*}) is large enough. In the context of the scattering of two scalars, it is shown that the differential scattering cross section has a piece that can, under certain conditions, rise with energy. Concrete examples of scattering near a black hole and a neutron star are considered and the behaviour of differential scattering cross-sections in these cases is derived. In particular, it is shown that gravitational corrections to scattering of scalars can become very significant at energy scales not too high, say, 25 TeV. (author). 13 refsPrimary Subject

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[en] The author have investigated the infrared divergence in QFT from the point of view of unitarity and analyticity. The author have shown that in QED, the infrared divergence for the imaginary part of a bubble diagram at any order of α would be canceled each other between the set of cutting-bubble diagrams got from cutting rules of Landau Cutkosky. From the concept of generalized optical theorem and the hypothesis of analyticity of the scattering amplitude, the author have drawn the physical connotation from the general formula of unitarity for 'forward scattering processes', and thus got a criterion in QED for whether in a process there exist infrared divergence or not. Also from the variation of thresholds of a bubble diagram of π(q

^{2}) in the -q^{2}plane as the photon mass λ approaches to zero, the author have shown diagrammatically how the infrared divergence in the corresponding cutting-bubble diagrams be canceled between them. At the end, the author gives a short discussion about difficulties and problems for treating infrared divergence in QCDPrimary Subject

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[en] We show here the equivalence between Gaussian effective potentials and Bogoliubov transformations. The latter are used to study the vacuum structure of the O(N) symmetric Thirring model variationally. The dynamical generation of mass gap is shown and the β function for the coupling in the same model is also calculated. (author)

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Journal of Physics. G, Nuclear and Particle Physics; ISSN 0954-3899; ; CODEN JPGPED; v. 18(8); p. 1301-1308

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