6,780 research outputs found
The non-local content of quantum operations
We show that quantum operations on multi-particle systems have a non-local
content; this mirrors the non-local content of quantum states. We introduce a
general framework for discussing the non-local content of quantum operations,
and give a number of examples. Quantitative relations between quantum actions
and the entanglement and classical communication resources needed to implement
these actions are also described. We also show how entanglement can catalyse
classical communication from a quantum action.Comment: 7 page
Spruce Budworm and Other Lepidopterous Prey of Eumenid Wasps (Hymenoptera: Eumenidae) in Spruce-Fir Forests of Maine
Three species of eumenid wasps, Ancistrocerus adiabatus, Ancistrocerus antilope, and Euodynerus Ieucomelas, accepted and provisioned trap-nesting blocks with lepidopterous larvae, A pyralid. Nephopteryx sp., was the most commonly provisioned prey. A. adiabarus and E. leucomelas preyed on late instars of the spruce budworm, Choristoneura fumiferana: however. budworms accounted for only 6% of the provisioned prey. Estimates of budworm population densities before and after wasp predation, and subsample-s of provisioned prey indicated no significant reductions i = 0.065%) in budworm populations attributable to trap-nesting wasps
Lorentz Invariance Violation and its Role in Quantum Gravity Phenomenology
The notion that gravitation might lead to a breakdown of standard space-time
structure at small distances, and that this might affect the propagation of
ordinary particles has led to a program to search for violations of Lorentz
invariance as a probe of quantum gravity. Initially it was expected that
observable macroscopic effects caused by microscopic violations of Lorentz
invariance would necessarily be suppressed by at least one power of the small
ratio between the Planck length and macroscopic lengths. Here we discuss the
implications of the fact that this expectation is in contradiction with
standard properties of radiative corrections in quantum field theories. In
normal field theories, radiative corrections in the presence of microscopic
Lorentz violation give macroscopic Lorentz violation that is suppressed only by
the size of Standard Model couplings, in clear conflict with observation. In
general, this conclusion can only be avoided by extreme fine tuning of the
parameters of the theory.Comment: Draft chapter contributed to the book "Towards quantum gravity",
being prepared by Daniele Oriti for Cambridge University Pres
The Effect of Dry Needling to the Multifidus Muscle on Resting and Contracted Thickness of Transversus Abdominis in Subjects with Low Back Pain
Study Design: Randomized, double-blinded, controlled clinical trial. Objective: To measure the effects of dry needling to the lumbar multifidus (MF) muscle for any change in resting and contracted thickness of the transversus abdominis (TrA) muscle as well as symptoms and disability in individuals with low back pain (LBP). Background: Recent studies have demonstrated that individuals with LBP have diminished co-activation of the lumbar MF and TrA muscles, which when working appropriately in healthy individuals, contributes to spinal stability and function. A significant change in the resting and contracted thickness of TrA has been found with dry needling to the lumbar MF in healthy subjects, but this has yet to be studied in individuals with low back pain. Methods: Thirty adults with LBP were randomly assigned to receive dry needling intervention or a sham needling intervention to the lumbar MF. The participants received instruction on the deep corset contraction (DCC) for purposes of measuring TrA muscle relaxation and contracted thickness with real time ultrasound (US) imaging pre- and post-intervention. Along with the US measurements, the Oswestry Disability Index (ODI), the Global Rating of Change Scale (GROC) and the Numeric Pain Rating Scale (NPRS) were used to measure outcomes at baseline, immediately post-, 2-days post, and 7-days post intervention. (See pdf for full abstract
Next-to-leading order QCD corrections to hadron+jet production in pp collisions at RHIC
We compute the next-to-leading order QCD corrections to the spin-independent
and spin-dependent cross-sections for the production of a single-hadron
accompanied by an opposite jet in hadronic collisions.
This process is being studied experimentally at RHIC, providing a new tool to
unveil the polarized gluon distribution Delta g. We perform a detailed analysis
of the phenomenological impact of the observable at NLO accuracy and show that
the preliminary data by the STAR collaboration confirms the idea of a small
gluon polarization in the 0.05<x<0.3 range.Comment: 16 pages, 11 Figures included. Minor typos correcte
Cardiac myoglobin deficit has evolved repeatedly in teleost fishes
Peer reviewedPublisher PD
Broadband sensitivity enhancement of detuned dual-recycled Michelson interferometers with EPR entanglement
We demonstrate the applicability of the EPR entanglement squeezing scheme for
enhancing the shot-noise-limited sensitivity of a detuned dual-recycled
Michelson interferometers. In particular, this scheme is applied to the
GEO\,600 interferometer. The effect of losses throughout the interferometer,
arm length asymmetries, and imperfect separation of the signal and idler beams
are considered
Global analysis of fragmentation functions for pions and kaons and their uncertainties
We present new sets of pion and kaon fragmentation functions obtained in NLO
combined analyses of single-inclusive hadron production in electron-positron
annihilation, proton-proton collisions, and deep-inelastic lepton-proton
scattering with either pions or kaons identified in the final state. At
variance with all previous fits, the present analyses take into account data
where hadrons of different electrical charge are identified, which allow to
discriminate quark from anti-quark fragmentation functions without the need of
non trivial flavor symmetry assumptions. The resulting sets are in good
agreement with all data analyzed, which cover a much wider kinematical range
than in previous fits. An extensive use of the Lagrange multiplier technique is
made in order to assess the uncertainties in the extraction of the
fragmentation functions and the synergy from the complementary data sets in our
global analysis.Comment: 28 pages, 25 figure
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