26,440 research outputs found

    Towards a warped inflationary brane scanning

    Full text link
    We present a detailed systematics for comparing warped brane inflation with the observations, incorporating the effects of both moduli stabilization and ultraviolet bulk physics. We explicitly construct an example of the inflaton potential governing the motion of a mobile D3 brane in the entire warped deformed conifold. This allows us to precisely identify the corresponding scales of the cosmic microwave background. The effects due to bulk fluxes or localized sources are parametrized using gauge/string duality. We next perform some sample scannings to explore the parameter space of the complete potential, and first demonstrate that without the bulk effects there can be large degenerate sets of parameters with observationally consistent predictions. When the bulk perturbations are included, however, the observational predictions are generally spoiled. For them to remain consistent, the magnitudes of the bulk effects need to be highly suppressed via fine tuning.Comment: (v1) 11 pages, 2 figures, 2 tables; (v2) more clarifications and references added; (v3) 12 pages, more discussions, to appear in Physical Review

    Lyapunov Spectra in SU(2) Lattice Gauge Theory

    Full text link
    We develop a method for calculating the Lyapunov characteristic exponents of lattice gauge theories. The complete Lyapunov spectrum of SU(2) gauge theory is obtained and Kolmogorov-Sinai entropy is calculated. Rapid convergence with lattice size is found.Comment: 7pp, DUKE-TH-93-5

    Breaking scale invariance from a singular inflaton potential

    Full text link
    In this paper we break the scale invariance of the primordial power spectrum of curvature perturbations of inflation. Introducing a singular behaviour due to spontaneous symmetry breaking in the inflaton potential, we obtain fully analytic expressions of scale dependent oscillation and a modulation in power on small scale in the primordial spectrum. And we give the associated cosmic microwave background and matter power spectra which we can observe now and discuss the signature of the scale dependence. We also address the possibility of whether some inflationary model with featured potential might mimic the predictions of the scale invariant power spectrum. We present some examples which illustrate such degeneracies.Comment: 20 pages, 9 figures; Discussion expanded and references added; Miscellaneous typos correcte

    The Sorting Index and Permutation Codes

    Get PDF
    In the combinatorial study of the coefficients of a bivariate polynomial that generalizes both the length and the reflection length generating functions for finite Coxeter groups, Petersen introduced a new Mahonian statistic sorsor, called the sorting index. Petersen proved that the pairs of statistics (sor,cyc)(sor,cyc) and (inv,rl-min)(inv,rl\textrm{-}min) have the same joint distribution over the symmetric group, and asked for a combinatorial proof of this fact. In answer to the question of Petersen, we observe a connection between the sorting index and the B-code of a permutation defined by Foata and Han, and we show that the bijection of Foata and Han serves the purpose of mapping (inv,rl-min)(inv,rl\textrm{-}min) to (sor,cyc)(sor,cyc). We also give a type BB analogue of the Foata-Han bijection, and we derive the quidistribution of (invB,LmapB,RmilB)(inv_B,{\rm Lmap_B},{\rm Rmil_B}) and (sorB,LmapB,CycB)(sor_B,{\rm Lmap_B},{\rm Cyc_B}) over signed permutations. So we get a combinatorial interpretation of Petersen's equidistribution of (invB,nminB)(inv_B,nmin_B) and (sorB,lB′)(sor_B,l_B'). Moreover, we show that the six pairs of set-valued statistics (CycB,RmilB)\rm (Cyc_B,Rmil_B), (CycB,LmapB)\rm(Cyc_B,Lmap_B), (RmilB,LmapB)\rm(Rmil_B,Lmap_B), (LmapB,RmilB)\rm(Lmap_B,Rmil_B), (LmapB,CycB)\rm(Lmap_B,Cyc_B) and (RmilB,CycB)\rm(Rmil_B,Cyc_B) are equidistributed over signed permutations. For Coxeter groups of type DD, Petersen showed that the two statistics invDinv_D and sorDsor_D are equidistributed. We introduce two statistics nminDnmin_D and l~D′\tilde{l}_D' for elements of DnD_n and we prove that the two pairs of statistics (invD,nminD)(inv_D,nmin_D) and (sorD,l~D′)(sor_D,\tilde{l}_D') are equidistributed.Comment: 25 page

    QCD corrections to polarization of J/\psi and \Upsilon at Fermilab Tevatron and CERN LHC

    Full text link
    In this work, we present more detail of the calculation on the NLO QCD corrections to polarization of direct J/psi production via color singlet at Tevatron and LHC, as well as the results for Upsilon for the first time. Our results show that the J/psi polarization status drastically changes from transverse polarization dominant at LO into longitudinal polarization dominant in the whole range of the transverse momentum ptp_t of J/psi when the NLO corrections are counted. For Upsilon production, the p_t distribution of the polarization status behaves almost the same as that for J/psi except that the NLO result is transverse polarization at small p_t range. Although the theoretical evaluation predicts a larger longitudinal polarization than the measured value at Tevatron, it may provide a solution towards the previous large discrepancy for J/psi and Upsilon polarization between theoretical predication and experimental measurement, and suggests that the next important step is to calculate the NLO corrections to hadronproduction of color octet state J/psi^(8) and Upsilon^(8). Our calculations are performed in two ways, namely we do and do not analytically sum over the polarizations, and then check them with each other.Comment: 12 pages, 12 figures, two columns, use revtex4; to appear in PR

    Seething Horizontal Magnetic Fields in the Quiet Solar Photosphere

    Get PDF
    The photospheric magnetic field outside of active regions and the network has a ubiquitous and dynamic line-of-sight component that strengthens from disk center to limb as expected for a nearly horizontal orientation. This component shows a striking time variation with an average temporal rms near the limb of 1.7 G at ~3" resolution. In our moderate resolution observations the nearly horizontal component has a frequency variation power law exponent of -1.4 below 1.5 mHz and is spatially patchy on scales up to ~15 arcsec. The field may be a manifestation of changing magnetic connections between eruptions and evolution of small magnetic flux elements in response to convective motions. It shows no detectable latitude or longitude variations.Comment: 7 pages, 6 figures, submitted to ApJ letters, quality of figures significantly degraded here by compression requirement

    Inflation in minimal left-right symmetric model with spontaneous D-parity breaking

    Full text link
    We present a simplest inflationary scenario in the minimal left-right symmetric model with spontaneous D-parity breaking, which is a well motivated particle physics model for neutrino masses. This leads us to connect the observed anisotropies in the cosmic microwave background to the sub-eV neutrino masses. The baryon asymmetry via the leptogenesis route is also discussed briefly.Comment: (v1) 4 pages, 1 figure; (v2) typos corrected; (v3) title and abstract changed, numerical estimates given, minor changes; (v4) 5 pages, relations between the neutrino masses and the CMB fluctuations become more explicit, miscellaneous changes, to appear in Physical Review
    • …
    corecore