4,178 research outputs found
A theory of multiformat communication: mechanisms, dynamics, and strategies
Extant communication theories predate the explosion of digital formats and technological advances such as virtual reality, which likely explains their predominant focus on traditional and format-level (e.g., face-to-face, email) rather than digital or characteristic-level (e.g., visual cues, synchronicity) design decisions. Firms thus lack insights into how to create and use emerging digital formats, individually or synergistically. To establish a holistic framework of bilateral multiformat communication for relationship marketing, this article reviews communication theory to establish a foundation for understanding multiformat communication and to identify any gaps (e.g., AI agents, simulated cues). The authors then review bilateral communication research in light of the identified theoretical gaps, to inform their framework. Finally, by decomposing these formats according to six fundamental characteristics, they predict how each characteristic might promote effective, efficient, and experiential communication goals, in light of distinct message, temporal, and dyadic factors. Ultimately, these combined insights reveal an overarching framework, with characteristic-level propositions grouped into five key themes, that can serve as a platform for academics and managers to develop multiformat communication theory and relationship strategies
Gravitational Wave Emission from the Single-Degenerate Channel of Type Ia Supernovae
The thermonuclear explosion of a C/O white dwarf as a Type Ia supernova (SN
Ia) generates a kinetic energy comparable to that released by a massive star
during a SN II event. Current observations and theoretical models have
established that SNe Ia are asymmetric, and therefore--like SNe II--potential
sources of gravitational wave (GW) radiation. We perform the first detailed
calculations of the GW emission for a SN Ia of any type within the
single-degenerate channel. The gravitationally-confined detonation (GCD)
mechanism predicts a strongly-polarized GW burst in the frequency band around 1
Hz. Third-generation spaceborne GW observatories currently in planning may be
able to detect this predicted signal from SNe Ia at distances up to 1 Mpc. If
observable, GWs may offer a direct probe into the first few seconds of the SNe
Ia detonation.Comment: 8 pages, 4 figures, Accepted by Physical Review Letter
Black Rings, Boosted Strings and Gregory-Laflamme
We investigate the Gregory-Laflamme instability for black strings carrying
KK-momentum along the internal direction. We demonstrate a simple kinematical
relation between the thresholds of the classical instability for the boosted
and static black strings. We also find that Sorkin's critical dimension depends
on the internal velocity and in fact disappears for sufficiently large boosts.
Our analysis implies the existence of an analogous instability for the
five-dimensional black ring of Emparan and Reall. We also use our results for
boosted black strings to construct a simple model of the black ring and argue
that such rings exist in any number of space-time dimensions.Comment: 26 pages, 6 figure
Quantum-limited estimation of the axial separation of two incoherent point sources
Improving axial resolution is crucial for three-dimensional optical imaging
systems. Here we present a scheme of axial superresolution for two incoherent
point sources based on spatial mode demultiplexing. A radial mode sorter is
used to losslessly decompose the optical fields into a radial mode basis set to
extract the phase information associated with the axial positions of the point
sources. We show theoretically and experimentally that, in the limit of a zero
axial separation, our scheme allows for reaching the quantum Cram\'er-Rao lower
bound and thus can be considered as one of the optimal measurement methods.
Unlike other superresolution schemes, this scheme does not require neither
activation of fluorophores nor sophisticated stabilization control. Moreover,
it is applicable to the localization of a single point source in the axial
direction. Our demonstration can be useful to a variety of applications such as
far-field fluorescence microscopy.Comment: Comments are welcom
Colloquium: Understanding Quantum Weak Values: Basics and Applications
Since its introduction 25 years ago, the quantum weak value has gradually
transitioned from a theoretical curiosity to a practical laboratory tool. While
its utility is apparent in the recent explosion of weak value experiments, its
interpretation has historically been a subject of confusion. Here a pragmatic
introduction to the weak value in terms of measurable quantities is presented,
along with an explanation for how it can be determined in the laboratory.
Further, its application to three distinct experimental techniques is reviewed.
First, as a large interaction parameter it can amplify small signals above
technical background noise. Second, as a measurable complex value it enables
novel techniques for direct quantum state and geometric phase determination.
Third, as a conditioned average of generalized observable eigenvalues it
provides a measurable window into nonclassical features of quantum mechanics.
In this selective review, a single experimental configuration to discuss and
clarify each of these applications is used.Comment: 11 pages, 5 figures, published versio
A comparison of GC-FID and PTR-MS toluene measurements in ambient air under conditions of enhanced monoterpene loading
Toluene was measured using both a gas chromatographic system (GC), with a flame ionization detector (FID), and a proton transfer reaction-mass spectrometer (PTR-MS) at the AIRMAP atmospheric monitoring station Thompson Farm (THF) in rural Durham, NH during the summer of 2004. Simultaneous measurements of monoterpenes, including alpha- and beta-pinene, camphene, Delta(3)-carene, and d-limonene, by GC-FID demonstrated large enhancements in monoterpene mixing ratios relative to toluene, with median and maximum enhancement ratios of similar to 2 and similar to 30, respectively. A detailed comparison between the GC-FID and PTR-MS toluene measurements was conducted to test the specificity of PTR-MS for atmospheric toluene measurements under conditions often dominated by biogenic emissions. We derived quantitative estimates of potential interferences in the PTR-MS toluene measurements related to sampling and analysis of monoterpenes, including fragmentation of the monoterpenes and some of their primary carbonyl oxidation products via reactions with H(3)O(+), O(2)(+) and NO(+) in the PTR-MS drift tube. The PTR-MS and GC-FID toluene measurements were in good quantitative agreement and the two systems tracked one another well from the instrumental limits of detection to maximum mixing ratios of similar to 0.5 ppbv. A correlation plot of the PTR-MS versus GC-FID toluene measurements was described by the least squares regression equation y=(1.13 +/- 0.02)x-(0.008 +/- 0.003) ppbv, suggesting a small similar to 13% positive bias in the PTR-MS measurements. The bias corresponded with a similar to 0.055 ppbv difference at the highest measured toluene level. The two systems agreed quantitatively within the combined 1 sigma measurement precisions for 60% of the measurements. Discrepancies in the measured mixing ratios were not well correlated with enhancements in the monoterpenes. Better quantitative agreement between the two systems was obtained by correcting the PTR-MS measurements for contributions from monoterpene fragmentation in the PTR-MS drift tube; however, the improvement was minor (\u3c10%). Interferences in the PTRMS measurements from fragmentation of the monoterpene oxidation products pinonaldehyde, caronaldehyde and alpha-pinene oxide were also likely negligible. A relatively large and variable toluene background in the PTR-MS instrument likely drove the measurement bias; however, the precise contribution was difficult to accurately quantify and thus was not corrected for in this analysis. The results from THF suggest that toluene can be reliably quantified by PTR-MS using our operating conditions (drift tube pressure, temperature and voltage of 2.0 mbar, 45 degrees C and 600V, respectively) under the ambient compositions probed. This work extends the range of field conditions under which PTR-MS validation studies have been conducted
Approximating Turaev-Viro 3-manifold invariants is universal for quantum computation
The Turaev-Viro invariants are scalar topological invariants of compact,
orientable 3-manifolds. We give a quantum algorithm for additively
approximating Turaev-Viro invariants of a manifold presented by a Heegaard
splitting. The algorithm is motivated by the relationship between topological
quantum computers and (2+1)-D topological quantum field theories. Its accuracy
is shown to be nontrivial, as the same algorithm, after efficient classical
preprocessing, can solve any problem efficiently decidable by a quantum
computer. Thus approximating certain Turaev-Viro invariants of manifolds
presented by Heegaard splittings is a universal problem for quantum
computation. This establishes a novel relation between the task of
distinguishing non-homeomorphic 3-manifolds and the power of a general quantum
computer.Comment: 4 pages, 3 figure
Englacial architecture and age-depth constraints across the West Antarctic Ice Sheet
he englacial stratigraphic architecture of internal reflection horizons (IRHs) as imaged by ice‐penetrating radar (IPR) across ice sheets reflects the cumulative effects of surface mass balance, basal melt, and ice flow. IRHs, considered isochrones, have typically been traced in interior, slow‐flowing regions. Here, we identify three distinctive IRHs spanning the Institute and Möller catchments that cover 50% of West Antarctica's Weddell Sea Sector and are characterized by a complex system of ice stream tributaries. We place age constraints on IRHs through their intersections with previous geophysical surveys tied to Byrd Ice Core and by age‐depth modeling. We further show where the oldest ice likely exists within the region and that Holocene ice‐dynamic changes were limited to the catchment's lower reaches. The traced IRHs from this study have clear potential to nucleate a wider continental‐scale IRH database for validating ice sheet models
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Analysis of the hydration water around bovine serum albumin using terahertz coherent synchrotron radiation.
Terahertz spectroscopy was used to study the absorption of bovine serum albumin (BSA) in water. The Diamond Light Source operating in a low alpha mode generated coherent synchrotron radiation that covered a useable spectral bandwidth of 0.3-3.3 THz (10-110 cm(-1)). As the BSA concentration was raised, there was a nonlinear change in absorption inconsistent with Beer's law. At low BSA concentrations (0-1 mM), the absorption remained constant or rose slightly. Above a concentration of 1 mM BSA, a steady decrease in absorption was observed, which was followed by a plateau that started at 2.5 mM. Using a overlapping hydration layer model, the hydration layer was estimated to extend 15 Å from the protein. Calculation of the corrected absorption coefficient (αcorr) for the water around BSA by subtracting the excluded volume of the protein provides an alternative approach to studying the hydration layer that provides evidence for complexity in the population of water around BSA.This is the accepted version of an article first published in The Journal of Physical Chemistry A. The version of record is available from ACS Publications at http://pubs.acs.org/doi/abs/10.1021/jp407410
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