On the Price of Anarchy of Highly Congested Nonatomic Network Games

We consider nonatomic network games with one source and one destination. We examine the asymptotic behavior of the price of anarchy as the inflow increases. In accordance with some empirical observations, we show that, under suitable conditions, the price of anarchy is asymptotic to one. We show with some counterexamples that this is not always the case. The counterexamples occur in very simple parallel graphs.Comment: 26 pages, 6 figure

Scheme for generating entangled states of two field modes in a cavity

This paper considers a two-level atom interacting with two cavity modes with equal frequencies. Applying a unitary transformation, the system reduces to the analytically solvable Jaynes-Cummings model. For some particular field states, coherent and squeezed states, the transformation between the two bare basis's, related by the unitary transformation, becomes particularly simple. It is shown how to generate, the highly non-classical, entangled coherent states of the two modes, both in the zero and large detuning cases. An advantage with the zero detuning case is that the preparation is deterministic and no atomic measurement is needed. For the large detuning situation a measurement is required, leaving the field in either of two orthogonal entangled coherent states.Comment: Accepted in J. Mod. Opt.; 12 pages; Replaced with revised version. Extended discussion of experimental realizations, earlier studies in the field and on the frequency dependence in the adiabatic eliminatio

Gapped continuum Kaluza-Klein spectrum

We consider a warped ve-dimensional model with an ultraviolet (UV) brane and, on top of the Standard Model isolated modes, continua of KK modes with different mass gaps for all particles: gauge bosons, fermions, graviton, radion and Higgs boson. The model can be considered as a modelization in ve dimensions of gapped unparticles. The ve dimensional metric has a singularity, at a finite (infinite) value of the proper (conformal) coordinate, which is admissible as it supports finite temperature in the form of a black hole horizon. An infrared (IR) brane, with particular jumping conditions, is introduced to trigger correct electroweak breaking. The gravitational metric is AdS5 near the UV brane, to solve the hierarchy problem with a fundamental Planck scale, and linear, in conformal coordinates, near the IR, as in the linear dilaton and ve-dimensional clockwork models. The branes, and singularity, distances are fixed, à la Goldberger-Wise, by a bulk scalar field with brane potentials explicitly breaking the conformal symmetry. The bosonic continuum of KK modes with the smallest mass gap are those of gauge bosons, and so they are the most likely produced at the LHC. Mass gaps of the continuum of KK fermions do depend on their localization in the extra dimension. We have computed the spectral functions, and arbitrary Green's functions, and shown how they can modify some Standard Model processes.The work of EM is supported by the Spanish MINEICO under Grant FIS2017-85053-C2-1-P, by the Junta de Andalucía under Grant FQM-225, by the Consejería de Conocimiento, Investigación y Universidad of the Junta de Andalucía and European Regional Development Fund (ERDF) under Grant SOMM17/6105/UGR, and by the Spanish Consolider Ingenio 2010 Programme CPAN under Grant CSD2007-00042. The research of EM is also supported by the Ramón y Cajal Program of the Spanish MINEICO under Grant RYC-2016-20678. The work of MQ is partly supported by Spanish MINEICO (Grant FPA2017-88915-P), by the Catalan Government under Grant 2017SGR1069, and by Severo Ochoa Excellence Program of MINEICO (Grant SEV-2016-0588)

Diffractive Higgs Production by AdS Pomeron Fusion

The double diffractive Higgs production at central rapidity is formulated in terms of the fusion of two AdS gravitons/Pomerons first introduced by Brower, Polchinski, Strassler and Tan in elastic scattering. Here we propose a simple self-consistent holographic framework capable of providing phenomenologically compelling estimates of diffractive cross sections at the LHC. As in the traditional weak coupling approach, we anticipate that several phenomenological parameters must be tested and calibrated through factorization for a self-consistent description of other diffractive process such as total cross sections, deep inelastic scattering and heavy quark production in the central region.Comment: 53 pages, 8 figure

The interaction between practice and performance pressure on the planning and control of fast target directed movement

Pressure to perform often results in decrements to both outcome accuracy and the kinematics of motor skills. Furthermore, this pressure-performance relationship is moderated by the amount of accumulated practice or the experience of the performer. However, the interactive effects of performance pressure and practice on the underlying processes of motor skills are far from clear. Movement execution involves both an offline pre-planning process and an online control process. The present experiment aimed to investigate the interaction between pressure and practice on these two motor control processes. Two groups of participants (control and pressure; N = 12 and 12, respectively) practiced a video aiming amplitude task and were transferred to either a non-pressure (control group) or a pressure condition (pressure group) both early and late in practice. Results revealed similar accuracy and movement kinematics between the control and pressure groups at early transfer. However, at late transfer, the introduction of pressure was associated with increased performance compared to control conditions. Analysis of kinematic variability throughout the movement suggested that the performance increase was due to participants adopting strategies to improve movement planning in response to pressure reducing the effectiveness of the online control system

Identifying the colour of TeV-scale resonances

We explore how the colour of any new TeV-scale resonances that decay into top quark pairs can be identified by studying the dependence of the observed cross-section on a central jet veto. To facilitate this study, colour octet resonance production was implemented in Pythia8 and colour singlet resonance production is simulated after minor modifications. We find that the colour of a 2 TeV resonance can be identified with 10/fb of data at a centre-of-mass energy of 14 TeV for a wide range of couplings, but only if the uncertainty in the theoretical prediction is dramatically reduced from its current level.Comment: 18 pages, 10 figure

Foetal haemoglobin, blood transfusion, and retinopathy of prematurity in very preterm infants:A pilot prospective cohort study

Purpose To identify if there is an association between foetal haemoglobin (HbF) concentration and retinopathy of prematurity (ROP) in very preterm infants. Patients and methods Prospective cohort study. Infants born <32 weeks’ gestational age or <1501 g in two tertiary neonatal units between January 2012 and May 2013 (n=42) were enrolled. HbF and adult haemoglobin (HbA) concentrations were measured using high-pressure liquid chromatography from blood samples sent as part of routine neonatal care once routinely requested laboratory tests had been performed. Clinical data were obtained from case notes. We calculated odds ratios (ORs) (95% confidence intervals (CIs)) to quantify the relationship between initial and mean %HbF with ROP severity (none, stages 1–3). Results A total of 42 infants were recruited: mean gestation 28.0 weeks (SD 1.91); mean birth weight 1042 g (SD 264). Six infants died before ROP screening; 14/36 developed ROP (39%); and 22/36 (61%) did not. Infants who developed ROP had similar initial %HbF (83.3 vs 92.3%, P=0.06), but significantly lower mean %HbF (61.75 vs 91.9%, P=0.0001) during their inpatient stay than those who did not develop ROP. In ordinal logistic regression models adjusted for birth weight, gestation and transfusion volume, mean post-natal %HbF was negatively associated with ROP severity: adjusted OR 0.94 (0.90–0.99), while initial %HbF at birth was not: adjusted OR 1.05 (0.97–1.16). Conclusion Replacing HbF by HbA during transfusion may promote ROP development by rapidly increasing oxygen availability to the retina. Conversely, maintaining a higher %HbF may be a protective factor against ROP

QCD and strongly coupled gauge theories : challenges and perspectives

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe