2,968 research outputs found

    Experimental demonstration of coupled optical springs

    Get PDF
    Optical rigidity will play an important role in improving the sensitivity of future generations of gravitational wave (GW) interferometers, which employ high laser power in order to reach and exceed the standard quantum limit. Several experiments have demonstrated the combined effect of two optical springs on a single system for very low-weight mirror masses or membranes. In this paper we investigate the complex interactions between multiple optical springs and the surrounding apparatus in a system of comparable dynamics to a large-scale GW detector. Using three 100 g mirrors to form a coupled cavity system capable of sustaining two or more optical springs, we demonstrate a number of different regimes of opto-mechanical rigidity and measurement techniques. Our measurements reveal couplings between each optical spring and the control loops that can affect both the achievable increase in sensitivity and the stability of the system. Hence this work establishes a better understanding of the realisation of these techniques and paves the way to their application in future GW observatories, such as upgrades to Advanced LIGO

    It’s Still Bullshit: Reply to Dalton (2016)

    Get PDF
    In reply to Dalton (2016), the authors argue that bullshit is defined in terms of how it is produced, not how it is interpreted. They agree that it can be interpreted as profound by some readers (and assumed as much in the original paper). Nonetheless, they present additional evidence against the possibility that more reflective thinkers are more inclined to interpret bullshit statements as profound

    On the Reception and Detection of Pseudo-profound Bullshit

    Get PDF
    Although bullshit is common in everyday life and has attracted attention from philosophers, its reception (critical or ingenuous) has not, to our knowledge, been subject to empirical investigation. Here we focus on pseudo-profound bullshit, which consists of seemingly impressive assertions that are presented as true and meaningful but are actually vacuous. We presented participants with bullshit statements consisting of buzzwords randomly organized into statements with syntactic structure but no discernible meaning (e.g., “Wholeness quiets infinite phenomena”). Across multiple studies, the propensity to judge bullshit statements as profound was associated with a variety of conceptually relevant variables (e.g., intuitive cognitive style, supernatural belief). Parallel associations were less evident among profundity judgments for more conventionally profound (e.g., “A wet person does not fear the rain”) or mundane (e.g., “Newborn babies require constant attention”) statements. These results support the idea that some people are more receptive to this type of bullshit and that detecting it is not merely a matter of indiscriminate skepticism but rather a discernment of deceptive vagueness in otherwise impressive sounding claims. Our results also suggest that a bias toward accepting statements as true may be an important component of pseudo-profound bullshit receptivity

    Design of a speed meter interferometer proof-of-principle experiment

    Get PDF
    The second generation of large scale interferometric gravitational wave detectors will be limited by quantum noise over a wide frequency range in their detection band. Further sensitivity improvements for future upgrades or new detectors beyond the second generation motivate the development of measurement schemes to mitigate the impact of quantum noise in these instruments. Two strands of development are being pursued to reach this goal, focusing both on modifications of the well-established Michelson detector configuration and development of different detector topologies. In this paper, we present the design of the world's first Sagnac speed meter interferometer which is currently being constructed at the University of Glasgow. With this proof-of-principle experiment we aim to demonstrate the theoretically predicted lower quantum noise in a Sagnac interferometer compared to an equivalent Michelson interferometer, to qualify Sagnac speed meters for further research towards an implementation in a future generation large scale gravitational wave detector, such as the planned Einstein Telescope observatory.Comment: Revised version: 16 pages, 6 figure

    Long-term effects of chronic buspirone during adolescence reduce the adverse influences of neonatal inflammatory pain and stress on adaptive behavior in adult male rats

    Get PDF
    Neonatal pain and stress induce long-term changes in pain sensitivity and behavior. Previously we found alterations in pain sensitivity in adolescent rats exposed to early-life adverse events. We tested whether these alterations have long-lasting effects and if those effects can be improved by the 5-hydroxytryptamine 1A (5-HT1A) receptor agonist buspirone injected chronically during the adolescent period. This study investigates: (1) effects of inflammatory pain (the injection of formalin into the pad of a hind paw) or stress (short maternal deprivation-isolation, MI), or their combination in 1â\u80\u932-day-old rats on the adult basal pain, formalin-induced pain, anxiety and depression; (2) effects of adolescent buspirone in adult rats that experienced similar early-life insults. Changes in nociceptive thresholds were evaluated using the hot plate (HP) and formalin tests; levels of anxiety and depression were assessed with the elevated plus maze and forced swim tests respectively. Both neonatal painful and stressful treatments induced long-term alterations in the forced swim test. Other changes in adult behavioral responses were dependent on the type of neonatal treatment. There was a notable lack of long-term effects of the combination of early inflammatory pain and stress of MI on the pain responses, anxiety levels or on the effects of adolescent buspirone. This study provides the first evidence that chronic injection of buspirone in adolescent rats alters antinociceptive and anxiolytic effects limited to adult rats that showed behavioral alterations induced by early-life adverse treatments. These data highlight the role of 5-HT1A receptors in long-term effects of neonatal inflammatory pain and stress of short MI on adaptive behavior and possibility of correction of the pain and psychoemotional behavior that were altered by adverse pain/stress intervention using buspirone during critical adolescent period

    A Multicenter Phase 2 Study Incorporating High-Dose Rituximab into the CODOX-M/IVAC Regimen for Untreated Burkitt’s Lymphoma (BL): Examination of Correlative Serum and CSF Rituximab Levels

    Get PDF
    Background: Two-year survival rates for adult BL remain Methods: Twenty-five BL patients were enrolled. Patients had low-risk (LR) or high-risk (HR) disease; LR patients received 3 CODOX-M cycles, while HR had 4 alternating CODOX-M/IVAC cycles (Mead et al. Blood 2009). Rituximab (500mg/m2) was given x 2 doses each cycle. Correlative analyses of paired serum and CSF Rituximab levels were obtained for cycles 1+3 at 24+72 hours. Results: There were 20 HR and 5 LR patients and median age was 44 years (range, 23-70). 3 HR and 1 LR patient were HIV+, while 15% of HR patients had CNS disease. Additionally, 35% of HR patients had bulk \u3e10 cm and 40% had bone marrow involvement. Myelosuppression and mucositis appeared comparable with prior CODOX-M/IVAC data. The overall remission rate after 2 cycles was 100% with 67% complete remission. At 34-month median follow-up, 2-year PFS and OS rates for all patients were 86% and 86%, respectively (LR 2-year PFS and OS: both 100%; HR 2-year PFS and OS: both 82%). Further, the 2-year PFS and OS for HR, HIV-negative patients were 91% and 91%, respectively (disease-specific survival 100%). Two patients died from progressive disease (both HIV+ HR). The median serum and CSF rituximab levels for these patients were compared with patients without relapse (Table 1). Interestingly, cycle 1, 24-hour serum Rituximab levels were significantly higher among patients without relapse compared with the two patients who relapsed/died (P=0.042). Cycle 3, 24-hour Rituximab levels were of borderline significance (P=0.06). Conclusions: The integration of Rituximab into CODOX-M/IVAC was associated with excellent survival rates, especially for HIV-negative BL. Further investigation of the predictive value of serum Rituximab levels is warranted

    Initial determination of the spins of the gluino and squarks at LHC

    Full text link
    In principle particle spins can be measured from their production cross sections once their mass is approximately known. The method works in practice because spins are quantized and cross sections depend strongly on spins. It can be used to determine, for example, the spin of the top quark. Direct application of this method to supersymmetric theories will have to overcome the challenge of measuring mass at the LHC, which could require high statistics. In this article, we propose a method of measuring the spins of the colored superpatners by combining rate information for several channels and a set of kinematical variables, without directly measuring their masses. We argue that such a method could lead to an early determination of the spin of gluino and squarks. This method can be applied to the measurement of spin of other new physics particles and more general scenarios.Comment: 23 pages, 8 figures, minor change

    Supersymmetry and the LHC Inverse Problem

    Full text link
    Given experimental evidence at the LHC for physics beyond the standard model, how can we determine the nature of the underlying theory? We initiate an approach to studying the "inverse map" from the space of LHC signatures to the parameter space of theoretical models within the context of low-energy supersymmetry, using 1808 LHC observables including essentially all those suggested in the literature and a 15 dimensional parametrization of the supersymmetric standard model. We show that the inverse map of a point in signature space consists of a number of isolated islands in parameter space, indicating the existence of "degeneracies"--qualitatively different models with the same LHC signatures. The degeneracies have simple physical characterizations, largely reflecting discrete ambiguities in electroweak-ino spectrum, accompanied by small adjustments for the remaining soft parameters. The number of degeneracies falls in the range 1<d<100, depending on whether or not sleptons are copiously produced in cascade decays. This number is large enough to represent a clear challenge but small enough to encourage looking for new observables that can further break the degeneracies and determine at the LHC most of the SUSY physics we care about. Degeneracies occur because signatures are not independent, and our approach allows testing of any new signature for its independence. Our methods can also be applied to any other theory of physics beyond the standard model, allowing one to study how model footprints differ in signature space and to test ways of distinguishing qualitatively different possibilities for new physics at the LHC.Comment: 55 pages, 30 figure
    • …
    corecore