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  1. Cavity QED experiments are natural hosts for non-equilibrium phases of matter supported by photon-mediated interactions. In this work, we consider a cavity QED simulation of the BCS model of superfluidity, by studying regimes where the cavity photons act as dynamical degrees of freedom instead of mere mediators of the interaction via virtual processes. We find an enhancement of long time coherence following a quench whenever the cavity frequency is tuned into resonance with the atoms. We discuss how this is equivalent to enhancement of non-equilibrium superfluidity and highlight similarities to an analogous phenomena recently studied in solid state quantum optics. We also discuss the conditions for observing this enhanced resonant pairing in experiments by including the effect of photon losses and inhomogeneous coupling in our analysis. 
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  2. We study the spatiotemporal spreading of correlations in an ensemble of spins due to dissipation characterized by short- and long-range spatial profiles. Such emission channels can be synthesized with tunable spatial profiles in lossy cavity QED experiments using a magnetic field gradient and a Raman drive with multiple sidebands. We consider systems initially in an uncorrelated state, and find that correlations widen and contract in a novel pattern intimately related to both the dissipative nature of the dynamical channel and its spatial profile. Additionally, we make a methodological contribution by generalizing nonequilibrium spin-wave theory to the case of dissipative systems and derive equations of motion for any translationally invariant spin chain whose dynamics can be described by a combination of Hamiltonian interactions and dissipative Lindblad channels. Our work aims at extending the study of correlation dynamics to purely dissipative quantum simulators and compare them with the established paradigm of correlations spreading in Hamiltonian systems. 
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  3. Spatial information understanding is fundamental to visual perception in Metaverse. Beyond the stereoscopic visual cues naturally carried in Metaverse, the human vision system may use other auxiliary information provided by any shadow casting or motion parallax available to perceive the 3D virtual world. However, the combined use of shadows and motion parallax to improve 3D perception have not been fully studied. In particular, when visualizing the combination of volumetric data and associated skeleton models in VR, how to provide the auxiliary visual cues to enhance observers’ perception of the structural information is a key yet underexplored topic. This problem is particularly challenging for visualization of data in biomedical research. In this paper, we focus on immersive analytics in neurobiology where the structural information includes the relative position of objects (nuclei / cell body) in the 3D space and the spatial measurement and connectivity of segments (axons and dendrites) in a model. We present a perceptual experiment designed for understanding the consequence of shadow casting and motion parallax in the neuron structures observation and the feedback and analysis of the experiment are reported and discussed. 
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  4. Abstract

    A new 36.17 MHz all‐sky meteor radar was installed at McMurdo Station Antarctica (77.8°S, 166.7°E) in February 2018 to provide wind measurements in the mesosphere and lower thermosphere (MLT) region (70–120 km). This instrument is the highest latitude meteor radar currently in operation in the southern hemisphere; it joins two other meteor radars within the Antarctic Circle. The radar will provide long‐term continuous wind measurements of the polar region, and contribute to a greater understanding of MLT dynamics. This work describes the radar hardware and its context with other instruments in the region. The paper provides an overview of the spatial and temporal variation in meteor echoes over the observation period of March 2018 through October 2021. It also provides an analysis of the mean winds and solar tides over the first three years of operation; including a description of an observed 12 hr summertime wind oscillation consistent with previously documented observations of a westward propagating 12 hr non‐migrating tide of zonal wavenumber 1.

     
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  5. null (Ed.)