3,187 research outputs found

    Dylan and the Novel

    Get PDF
    In 1996 I first wrote the Nobel Committee of the Swedish Academy, nominating Dylan for its Prize in literature. The idea to do so did not originate with me but with two Dylan afficianados in Norway, journalist Reidar Indrebo and attorney Gunnar Lunde. (Also, a number of other professors have supported Dylan's candidacy at various times in the past.) Mr. Indrebo and Mr. Lunde had written Allen Ginsberg seeking help with the nomination. (The nominator must be a member of the Swedish Academy, or professor of literature or language, or a past laureate in literature, or the president of a national writers' organization.) Ginsberg's office called and asked if I would like to write a nominating letter.Note: The Peformance Artistry of Bob Dylan: Conference Proceedings of the Caen Colloquiu

    How to Maximize the Capacity of General Quantum Noisy Channels

    Full text link
    A general quantum noisy channel is analyzed, wherein the transmitted qubits may experience symmetry-breaking decoherence, along with memory effects. We find the optimal basis not to be fully entangled, but a combination of factorized and partially-entangled states in the presence of memory, asymmetry and the state-bias of the noise. Capacity-maximization is shown to be achievable by combining temporal shaping of the transmitted qubits and optimal basis selection.Comment: 4 pages, 3 figure

    Dynamic mechanical response of polymer networks

    Full text link
    The dynamic-mechanical response of flexible polymer networks is studied in the framework of tube model, in the limit of small affine deformations, using the approach based on Rayleighian dissipation function. The dynamic complex modulus G* is calculated from the analysis of a network strand relaxation to the new equilibrium conformation around the distorted primitive path. Chain equilibration is achieved via a sliding motion of polymer segments along the tube, eliminating the inhomogeneity of the polymer density caused by the deformation. The characteristic relaxation time of this motion separates the low-frequency limit of the complex modulus from the high-frequency one, where the main role is played by chain entanglements, analogous to the rubber plateau in melts. The dependence of storage and loss moduli, G' and G'', on crosslink and entanglement densities gives an interpolation between polymer melts and crosslinked networks. We discuss the experimental implications of the rather short relaxation time and the slow square-root variation of the moduli and the loss factor tan at higher frequencies.Comment: Journal of Chemical Physics (Oct-2000); Lates, 4 EPS figures include

    High energy resummation of direct photon production at hadronic colliders

    Get PDF
    Direct photon production is an important process at hadron colliders, being relevant both for precision measurement of the gluon density, and as background to Higgs and other new physics searches. Here we explore the implications of recently derived results for high energy resummation of direct photon production for the interpretation of measurements at the Tevatron and the LHC. The effects of resummation are compared to various sources of theoretical uncertainties like PDFs and scale variations. We show how the high--energy resummation procedure stabilizes the logarithmic enhancement of the cross section at high--energy which is present at any fixed order in the perturbative expansion starting at NNLO. The effects of high--energy resummation are found to be negligible at Tevatron, while they enhance the cross section by a few percent for p_T \lsim 10 GeV at the LHC. Our results imply that the discrepancy at small pTp_T between fixed order NLO and Tevatron data cannot be explained by unresummed high--energy contributions.Comment: 15 pages, 7 figure

    The role of answer fluency and perceptual fluency in the monitoring and control of reasoning: Reply to Alter, Oppenheimer, and Epley

    Get PDF
    In this reply, we provide an analysis of Alter et al. (2013) response to our earlier paper (Thompson et al., 2013). In that paper, we reported difficulty in replicating Alter, Oppenheimer, Epley, and Eyre’s (2007) main finding, namely that a sense of disfluency produced by making stimuli difficult to perceive, increased accuracy on a variety of reasoning tasks. Alter, Oppenheimer, and Epley (2013) argue that we misunderstood the meaning of accuracy on these tasks, a claim that we reject. We argue and provide evidence that the tasks were not too difficult for our populations (such that no amount of “metacognitive unease” would promote correct responding) and point out that in many cases performance on our tasks was well above chance or on a par with Alter et al.’s (2007) participants. Finally, we reiterate our claim that the distinction between answer fluency (the ease with which an answer comes to mind) and perceptual fluency (the ease with which a problem can be read) is genuine, and argue that Thompson et al. (2013) provided evidence that these are distinct factors that have different downstream effects on cognitive processe

    Conatraints on ΔG\Delta G from Prompt Photon plus Jet Production at HERA-N⃗\vec{N}

    Full text link
    The utility of prompt photon plus associated jet production for constraining the size and shape of the polarized gluon density of the proton ΔG\Delta G is examined at S=40\sqrt{S}=40 GeV, appropriate for the proposed HERA-N⃗\vec{N} polarized p⃗p⃗\vec{p}\vec{p} collider experiment. The calculation is performed at next-to-leading order (O(ααs2\alpha\alpha_s^2)) in QCD. The reliability of the predictions are examined in some detail.Comment: 16 pages, 3 figure

    High-energy resummation in direct photon production

    Get PDF
    We present the computation of the direct photon production cross-section in perturbative QCD to all orders in the limit of high partonic center-of-mass energy. We show how the high-energy resummation can be performed consistently in the presence of a collinear singularity in the final state, we compare our results to the fixed order NLO cross-section in MSbar scheme, and we provide predictions at NNLO and beyond.Comment: 16 pages, 5 figure
    • 

    corecore