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Sharing retrospectively acquired data is essential for both clinical research and training. Synthetic Data Generation (SDG), using Artificial Intelligence (AI) models, can overcome privacy barriers in sharing clinical data, enabling advancements in medical diagnostics. This study focuses on the clinical evaluation of medical SDG, with a proof-of-concept investigation on diagnosing Inflammatory Bowel Disease (IBD) using Wireless Capsule Endoscopy (WCE) images. The paper contributes by a) presenting a protocol for the systematic evaluation of synthetic images by medical experts and b) applying it to assess TIDE-II, a novel variational autoencoder-based model for high-resolution WCE image synthesis, with a comprehensive qualitative evaluation conducted by 10 international WCE specialists, focusing on image quality, diversity, realism, and clinical decision-making. The results show that TIDE-II generates clinically relevant WCE images, helping to address data scarcity and enhance diagnostic tools. The proposed protocol serves as a reference for future research on medical image-generation techniques.

Context. The formation of stars has been subject to extensive studies in the past decades from molecular cloud to protoplanetary disk scales. It is still not fully understood how the surrounding material in a protostellar system, that often shows asymmetric structures with complex kinematic properties, feeds the central protostar(s) and their disk(s). Aims. We study the spatial morphology and kinematic properties of the molecular gas surrounding the IRS3A and IRS3B protostellar systems in the L1448N region located in the Perseus molecular cloud. Methods. We present 1 mm NOEMA observations of the PRODIGE large program and analyze the kinematic properties of molecular lines. Given the complexity of the spectral profiles, the lines are fitted with up to three Gaussian velocity components. The clustering algorithm DBSCAN is used to disentangle the velocity components into the underlying physical structure. Results. We discover an extended gas bridge (~3000 au) surrounding both the IRS3A and IRS3B systems in six molecular line tracers (C18O, SO, DCN, H2CO, HC3N, and CH3OH). This gas bridge is oriented along the northeast-southwest direction and shows clear velocity gradients on the order of 100 km/s/pc towards the IRS3A system. We find that the observed velocity profile is consistent with analytical streamline models of gravitational infall towards IRS3A. The high-velocity C18O (2-1) emission towards IRS3A indicates a protostellar mass of ~1.2 Msun. Conclusions. While high angular resolution continuum data often show IRS3A and IRS3B in isolation, molecular gas observations reveal that these systems are still embedded within a large-scale mass reservoir with a complex spatial morphology as well as velocity profiles. The kinematic properties of the extended gas bridge are consistent with gravitational infall toward the IRS3A protostar., Comment: 16 pages, 10 figures; accepted for publication in A&A

We present HIP 8522, a young solar twin with the lowest detected lithium, potentially a field blue straggler or the result of episodic early accretion. Its stellar parameters ($T_{\rm eff} = 5729 \pm 7$ K, $\log g = 4.532 \pm 0.016$ dex, $\rm{[Fe/H]} = 0.005 \pm 0.010$ dex, $v_{t} = 1.08 \pm 0.02$ km s$^{-1}$) and chemical composition were determined via spectroscopic equilibrium using high resolution spectra ($R = 60~000-165~000$). The age of HIP 8522 was estimated to be an upper limit of $<$1 Gyr through isochrone fitting and was further confirmed using chemical clocks. Spectral synthesis of the lithium line at $\sim$6707.8 \AA\ yielded an upper lithium abundance limit of $A(\rm{Li}) <$ 0.8 dex. This value is unusually low for solar twins of similar age, which typically have $A(\rm{Li})$ values ranging from 2.0 to 3.3 dex, suggesting that $\sim$2 dex of lithium is missing. We investigate various scenarios, such as planet engulfment, sub-stellar mergers, and extra mixing. However, two distinct hypotheses provide plausible explanations for the significant depletion of lithium: one suggests that HIP 8522 is a field blue straggler formed by the merger of a close binary, while the other proposes that HIP 8522 experienced early episodic accretion. The young solar twin HIP 8522 presents an exceptional opportunity to rigorously test stellar evolution models and gain crucial insights into the internal mixing mechanisms responsible for the significant destruction of lithium.

Soft robots are known for their ability to perform tasks with great adaptability, enabled by their distributed, non-uniform stiffness and actuation. Bending is the most fundamental motion for soft robot design, but creating robust, and easy-to-fabricate soft bending joint with tunable properties remains an active problem of research. In this work, we demonstrate an inflatable actuation module for soft robots with a defined bending plane enabled by forced partial wrinkling. This lowers the structural stiffness in the bending direction, with the final stiffness easily designed by the ratio of wrinkled and unwrinkled regions. We present models and experimental characterization showing the stiffness properties of the actuation module, as well as its ability to maintain the kinematic constraint over a large range of loading conditions. We demonstrate the potential for complex actuation in a soft continuum robot and for decoupling actuation force and efficiency from load capacity. The module provides a novel method for embedding intelligent actuation into soft pneumatic robots.

We show that the spin of dark matter induces a gravitational analog of the electromagnetic Faraday effect, where the polarization of gravitational waves undergoes a rotation as they propagate through a dark matter halo with a non-vanishing axial spin tensor (hypermomentum). An expression for the gravitational rotation angle is provided, which is analogous to the Faraday rotation in optics, and evaluate its significance in astrophysical settings. Although the effect is expected to be small under current observational constraints, we discuss its potential importance in the early universe.

Context. Turbulence is a key component of molecular cloud structure. It is usually described by a cascade of energy down to the dissipation scale. The power spectrum for subsonic incompressible turbulence is $k^{-5/3}$, while for supersonic turbulence it is $k^{-2}$. Aims. We aim to determine the power spectrum in an actively star-forming molecular cloud, from parsec scales down to the expected magnetohydrodynamic (MHD) wave cutoff (dissipation scale). Methods. We analyze observations of the nearby NGC 1333 star-forming region in three different tracers to cover the different scales from $\sim$10 pc down to 20 mpc. The largest scales are covered with the low density gas tracer $^{13}$CO (1-0) obtained with single dish, the intermediate scales are covered with single-dish observations of the C$^{18}$O (3-2) line, while the smallest scales are covered in H$^{13}$CO$^+$ (1-0) and HNC (1-0) with a combination of NOEMA interferometer and IRAM 30m single dish observations. The complementarity of these observations enables us to generate a combined power spectrum covering more than two orders of magnitude in spatial scale. Results. We derive the power spectrum in an active star-forming region spanning more than 2 decades of spatial scales. The power spectrum of the intensity maps shows a single power-law behavior, with an exponent of 2.9$\pm$0.1 and no evidence of dissipation. Moreover, there is evidence for the power-spectrum of the ions to have more power at smaller scales than the neutrals, which is opposite from theoretical expectations. Conclusions. We show new possibilities of studying the dissipation of energy at small scales in star-forming regions provided by interferometric observations., Comment: 6 pages (+2 appendix), 5 figures. Accepted to A&A Letters. GitHub repo with code available at https://github.com/jpinedaf/NGC1333_NOEMA_turbulence

To date, we have access to enormous inventories of stellar spectra that allow the extraction of atmospheric parameters and chemical abundances essential in stellar studies. However, characterizing such a large amount of data is complex and requires a good understanding of the studied object to ensure reliable and homogeneous results. In this study, we present a methodology to measure homogenously the basic atmospheric parameters and detailed chemical abundances of over 1600 thin disk main-sequence stars in the 100 pc solar neighborhood, using APOGEE-2 infrared spectra. We employed the code tonalli to determine the atmospheric parameters using a prior on log g. The log g prior in tonalli implies an understanding of the treated population and helps to find physically coherent answers. Our atmospheric parameters agree within the typical uncertainties (100 K in Teff, 0.15 dex in log g and $[M/H]$) with previous estimations of ASPCAP and Gaia DR3. We use our temperatures to determine a new infrared color-temperature sequence, in good agreement with previous works, that can be used for any main-sequence star. Additionally, we used the BACCHUS code to determine the abundances of Mg, Al, Si, Ca, and Fe in our sample. The five elements (Mg, Al, Si, Ca, Fe) studied have an abundance distribution centered around slightly sub-solar values, in agreement with previous results for the solar neighborhood. The over 1600 main-sequence stars atmospheric parameters and chemical abundances presented here are useful in follow-up studies of the solar neighborhood or as a training set for data-driven methods., Comment: 20 pages, 15 figures, 6 tables, Accepted in MNRAS for publication

Starting from the isomorphism between the AdS Carroll and Poincar\'e algebras, we map the three-dimensional asymptotically flat solutions of Poincar\'e gravity into an AdS Carroll spacetime. We show the mapped solutions satisfy the field equations of the Chern-Simons formulation of AdS Carroll gravity and exhibit a Carroll geometry structure. Despite the presence of a negative cosmological constant in the mapped spacetime, the algebra of the canonical generators of the asymptotic symmetries is given by the $\mathfrak{bms}_3$ algebra., Comment: 15 pages

Haptic feedback enhances collision avoidance by providing directional obstacle information to operators during unmanned aerial vehicle (UAV) teleoperation. However, such feedback is often rendered via haptic joysticks, which are unfamiliar to UAV operators and limited to single direction force feedback. Additionally, the direct coupling between the input device and the feedback method diminishes an operators' sense of control and causes oscillatory movements. To overcome these limitations, we propose AeroHaptix, a wearable haptic feedback system that uses spatial vibrations to communicate multiple obstacle directions to operators simultaneously, without interfering the input control. The layout of vibrotactile actuators was determined via a perceptual study to eliminate perceptual biases and achieve uniform spatial coverage. A novel rendering algorithm, MultiCBF, extends control barrier functions to support multi-directional feedback. Our system evaluation showed that compared to the baseline condition, AeroHaptix effectively reduced the number of collisions and input disagreement. Additionally, operators reported that AeroHaptix was more helpful than the force feedback method, with comparable workload and situational awareness.

Excitons in transition metal dichalcogenides (TMDs) have emerged as a promising platform for novel applications ranging from optoelectronic devices to quantum optics and solid state quantum simulators. While much progress has been made towards characterizing and controlling excitons in TMDs, manipulating their properties during the course of their lifetime - a key requirement for many optoelectronic device and information processing modalities - remains an outstanding challenge. Here we combine long-lived interlayer excitons in angle-aligned MoSe$_2$/WSe$_2$ heterostructures with fast electrical control to realize dynamical control schemes, in which exciton properties are not predetermined at the time of excitation but can be dynamically manipulated during their lifetime. Leveraging the out-of-plane exciton dipole moment, we use electric fields to demonstrate dynamical control over the exciton emission wavelength. Moreover, employing a patterned gate geometry, we demonstrate rapid local sample doping and toggling of the radiative decay rate through exciton-charge interactions during the exciton lifetime. Spatially mapping the exciton response reveals charge redistribution, offering a novel probe of electronic transport in twisted TMD heterostructures. Our results establish the feasibility of dynamical exciton control schemes, unlocking new directions for exciton-based information processing and optoelectronic devices, and the realization of excitonic phenomena in TMDs., Comment: 37 pages, 4 figures in main text, 6 figures in supplemental materials; (v2) corrected funding acknowledgements

We aim to constrain the gas density and temperature distributions as well as gas masses in several T Tauri protoplanetary disks located in Taurus. We use the 12CO, 13CO, and C18O (2-1) isotopologue emission observed at 0.9 with the IRAM NOrthern Extended Millimeter Array (NOEMA) as part of the MPG-IRAM Observatory Program PRODIGE (PROtostars and DIsks: Global Evolution PIs: P. Caselli & Th. Henning). Our sample consists of Class II disks with no evidence of strong radial substructures. We use thesedata to constrain the thermal and chemical structure of these disks through theoretical models for gas emission. To fit the combined optically thick and thin CO line data in Fourier space, we developed the DiskCheF code, which includes the parameterized disk physical structure, machine-learning (ML) accelerated chemistry, and the RADMC-3D line radiative transfer module. A key novelty of DiskCheF is the fast and feasible ML-based chemistry trained on the extended grid of the disk physical-chemical models precomputed with the ANDES2 code. This ML approach allows complex chemical kinetics models to be included in a time-consuming disk fitting without the need to run a chemical code. We present a novel approach to incorporate chemistry into disk modeling without the need to explicitly calculate a chemical network every time. Using this new disk modeling tool, we successfully fit the 12CO, 13CO, and C18O (2-1) data from the CI, CY, DL, DM, DN, and IQ Tau disks. The combination of optically thin and optically thick CO lines allows us to simultaneously constrain the disk temperature and mass distribution, and derive the CO-based gas masses. These values are in reasonable agreement with the disk dust masses rescaled by a factor of 100 as well as with other indirect gas measurements., Comment: 25 pages, 19 figures

Using quantum state discrimination theory, we derive the upper bound for spoofing detection when randomly encoding two quantum states in an electromagnetic signal. We derive an analytic expression for the optimal bound and demonstrate that it can be saturated using a pair of coherent states. We show that quantum enhancement is independent of the number of photons; therefore, the single-photon restriction is unnecessary for experimental demonstration. We also consider encoding squeezed states in the signal and show that the detection probability approaches unity if the spoofer capability is limited to coherent state generation.

The proliferation of applications using artificial intelligence (AI) systems has led to a growing number of users interacting with these systems through sophisticated interfaces. Human-computer interaction research has long shown that interfaces shape both user behavior and user perception of technical capabilities and risks. Yet, practitioners and researchers evaluating the social and ethical risks of AI systems tend to overlook the impact of anthropomorphic, deceptive, and immersive interfaces on human-AI interactions. Here, we argue that design features of interfaces with adaptive AI systems can have cascading impacts, driven by feedback loops, which extend beyond those previously considered. We first conduct a scoping review of AI interface designs and their negative impact to extract salient themes of potentially harmful design patterns in AI interfaces. Then, we propose Design-Enhanced Control of AI systems (DECAI), a conceptual model to structure and facilitate impact assessments of AI interface designs. DECAI draws on principles from control systems theory -- a theory for the analysis and design of dynamic physical systems -- to dissect the role of the interface in human-AI systems. Through two case studies on recommendation systems and conversational language model systems, we show how DECAI can be used to evaluate AI interface designs., Comment: Fixed issue with subsection titles

The detection of narrow channels of accretion toward protostellar disks, known as streamers, have increased in number in the last few years. However, it is unclear if streamers are a common feature around protostars that were previously missed, or if they are a rare phenomenon. Our goals are to obtain the incidence of streamers toward a region of clustered star formation and to trace the origins of their gas, to determine if they originate within the filamentary structure of molecular clouds or from beyond. We used combined observations of the nearby NGC 1333 star-forming region, carried out with the NOEMA interferometer and the IRAM 30m single dish. Our observations cover the area between the IRAS 4 and SVS 13 systems. We traced the chemically fresh gas within NGC 1333 with HC3N molecular gas emission and the structure of the fibers in this region with N2H+ emission. We fit multiple velocity components in both maps and used clustering algorithms to recover velocity-coherent structures. We find streamer candidates toward 7 out of 16 young stellar objects within our field of view. This represents an incidence of approximately 40\% of young stellar objects with streamer candidates when looking at a clustered star forming region. The incidence increases to about 60\% when we considered only embedded protostars. All streamers are found in HC3N emission. Given the different velocities between HC3N and N2H+ emission, and the fact that, by construction, N2H+ traces the fiber structure, we suggest that the gas that forms the streamers comes from outside the fibers. This implies that streamers can connect cloud material that falls to the filaments with protostellar disk scales., Comment: 22 pages, 15 figures, accepted for publication in Astronomy and Astrophysics. GitHub repository with code available at https://github.com/tere-valdivia/propstar_gasflow

Complex Organic Molecules (COMs) have been found toward low-mass protostars but the origins of the COM emission are still unclear. It can be associated with, for example, hot corinos, outflows, and/or accretion shock/disk atmosphere. We have conducted NOEMA observations toward SVS13A from the PROtostars & DIsks: Global Evolution (PRODIGE) program. Our previous \ce{DCN} observations reveal a possible infalling streamer, which may affect the chemistry of the central protobinary by inducing accretion outbursts and/or shocked gas. Here, we further analyze six O-bearing COMs: CH3OH, aGg'-(CH2OH)2, C2H5OH, CH2(OH)CHO, CH3CHO, and CH3OCHO. Although the COM emission is not spatially resolved, we constrain the source sizes to $\lesssim0.3-0.4$ arcsec (90$-$120 au) by conducting uv-domain Gaussian fitting. Interestingly, the high-spectral resolution data reveal complex line profiles with multiple peaks showing differences between these six O-bearing COMs. The LTE fitting unveils differences in excitation temperatures and emitting areas among these COMs. We further conduct multiple-velocity-component LTE fitting to decompose the line emission into different kinematic components. Up to 6 velocity components are found from the LTE modeling. The temperature, column density, and source size of these components from each COM are obtained. We find a variety in excitation temperatures ($100-500$ K) and source sizes (D$\sim10-70$ au) from these kinematic components from different COMs. The emission of each COM can trace several components and different COMs most likely trace different regions. Given this complex structure, we suggest that the central region is inhomogeneous and unlikely to be heated by only protostellar radiation. We conclude that accretion shocks induced by the large-scale infalling streamer likely exist and contribute to the complexity of the COM emission., Comment: 29 pages, 18 figures, accepted to A&A

We developed a grid of stellar rotation models for low-mass and solar-type Classical T Tauri stars (CTTS) ($0.3M_{\odot}

Electron fraction and cosmic-ray ionization rates (CRIR) in star-forming regions are important quantities in astrochemical modeling and are critical to the degree of coupling between neutrals, ions, and electrons, which regulates the dynamics of the magnetic field. However, these are difficult quantities to estimate. We aim to derive the electron fraction and CRIR maps of an active star-forming region. We combined observations of the nearby NGC 1333 star-forming region carried out with the NOEMA interferometer and IRAM 30-m single dish to generate high spatial dynamic range maps of different molecular transitions. We used the DCO$^+$ and H$^{13}$CO$^+$ ratio (in addition to complementary data) to estimate the electron fraction and produce cosmic-ray ionization rate maps. We derived the first large-area electron fraction and CRIR resolved maps in a star-forming region, with typical values of $10^{-6.5}$ and $10^{-16.5}$ s$^{-1}$, respectively. The maps present clear evidence of enhanced values around embedded young stellar objects (YSOs). This provides strong evidence for locally accelerated cosmic rays. We also found a strong enhancement toward the northwest region in the map that might be related either to an interaction with a bubble or to locally generated cosmic rays by YSOs. We used the typical electron fraction and derived a MHD turbulence dissipation scale of 0.054 pc, which could be tested with future observations. We found a higher cosmic-ray ionization rate compared to the canonical value for $N({\rm H_2})=10^{21}-10^{23}$ cm$^{-2}$ of $10^{-17}$ s$^{-1}$ in the region, and it is likely generated by the accreting YSOs. The high value of the electron fraction suggests that new disks will form from gas in the ideal-MHD limit. This indicates that local enhancements of $\zeta({\rm H_2})$, due to YSOs, should be taken into account in the analysis of clustered star formation., Comment: 13 pages, 13 Figures. Accepted to A&A. Abridged abstract. GitHub repo with code available at https://github.com/jpinedaf/NGC1333_NOEMA_Ions

We are performing a line survey of 8 planet-forming Class II disks in Taurus with the IRAM NOrthern Extended Millimeter Array (NOEMA), as a part of the MPG-IRAM Observatory Program PRODIGE (PROtostars and DIsks: Global Evolution; PIs: P. Caselli and Th. Henning). Compact and extended disks around T Tauri stars CI, CY, DG, DL, DM, DN, IQ Tau, and UZ Tau E are observed in ~80 lines from >20 C-, O,- N-, and S-bearing species. The observations in four spectral settings at 210-280 GHz with $1\sigma$ rms sensitivity of ~ 8-12 mJy/beam at 0.9" and 0.3 km/s resolution will be completed in 2024. The uv-visibilities are fitted with the DiskFit model to obtain key stellar and disk properties. In this paper, the combined $^{12}$CO, $^{13}$CO and C$^{18}$O $J = 2-1$ data are presented. We find that the CO fluxes and disk masses inferred from dust continuum tentatively correlate with the CO emission sizes. We constrain dynamical stellar masses, geometries, temperatures, the CO column densities and gas masses for each disk. The best-fit temperatures at 100 au are ~ 17-37 K, and decrease radially with the power-law exponent q ~ 0.05-0.76. The inferred CO column densities decrease radially with the power-law exponent p ~ 0.2-3.1. The gas masses estimated from $^{13}$CO (2-1) are ~ $0.001-0.2 M_\textrm{Sun}$. The best-fit CO column densities point to severe CO freeze-out in the disks. The DL Tau disk is an outlier, and has either stronger CO depletion or lower gas mass than the rest of the sample. The CO isotopologue ratios are roughly consistent with the observed values in disks and the low-mass star-forming regions., Comment: 47 pages, 10 figures, 6 tables, accepted for publication by A&A on 22/02/2024

We present a novel asymptotically anti-de Sitter black hole solution with conformally-coupled scalar fields in the first-order formalism of gravity in four dimensions. To do so, we consider a one-parameter extension of conformal transformations by exploiting the fact that the vielbein and spin connection are regarded as independent fields. We solve the field equations analytically and obtain a static black hole solution with nontrivial torsion sourced by the conformal coupling between the scalar field and geometry. The presence of torsion renders the scalar field everywhere regular, while the curvature and torsion singularities coalesce into the origin. We show that this configuration is continuously connected to previously reported solutions in the limit of vanishing torsion and analyze its main properties, focusing on the consequences of the torsional singularity., Comment: References added. Matches published version

We developed a tool that measures equivalent widths of various lines in low resolution optical spectra, and it was applied to stellar spectra obtained as part of SDSS-V and LAMOST programs. These lines, such as Li I which directly indicates stellar youth, or optical H I and Ca II which in emission indicate activity associated with stellar youth, are commonly seen in YSOs. We observe several notable differences in the properties of these lines between YSOs and the field stars. Using these data, we devise a set of criteria through which it is possible to confirm the youth of stars that have been observed by the ABYSS program, as well as to identify likely young stars that have serendipitously been observed by other programs. We examine the decrement of H lines seen in emission in CTTSs, and estimate the properties of the accretion stream that is responsible for the production of these lines. Finally, we examine the evolution of Li I as a function of age, and characterize the scatter in its abundance that appears to be intrinsic in young M dwarfs., Comment: 15 pages, 10 figures, accepted to AJ

Aims. We aim to study the structure and kinematics of the two filaments inside the subsonic core Barnard 5 in Perseus using high-resolution ($\approx$ 2400 au) NH3 data and a multi-component fit analysis. Methods. We used observations of NH3 (1,1) and (2,2) inversion transitions using the Very Large Array (VLA) and the Green Bank Telescope (GBT). We smoothed the data to a beam of 8'' to reliably fit multiple velocity components towards the two filamentary structures identified in B5. Results. Along with the core and cloud components, which dominate the flux in the line of sight, we detected two components towards the two filaments showing signs of infall. We also detected two additional components that can possibly trace new material falling into the subsonic core of B5. Conclusions. Following comparison with previous simulations of filament formation scenarios in planar geometry, we conclude that either the formation of the B5 filaments is likely to be rather cylindrically symmetrical or the filaments are magnetically supported. We also estimate infall rates of $1.6\times10^{-4}\,M_\odot\,yr^{-1}$ and $1.8\times10^{-4}\,M_\odot\,yr^{-1}$ (upper limits) for the material being accreted onto the two filaments. At these rates, the filament masses can change significantly during the core lifetime. We also estimate an upper limit of $3.5\times10^{-5}\,M_\odot\,yr^{-1}$ for the rate of possible infall onto the core itself. Accretion of new material onto cores indicates the need for a significant update to current core evolution models, where cores are assumed to evolve in isolation., Comment: 15 pages, 13 figures, accepted for publication on Astronomy and Astrophysics. The scripts used for the analysis presented in this paper can be found at https://github.com/SpandanCh/Barnard5_filaments

To meet the grand challenges of agricultural production including climate change impacts on crop production, a tight integration of social science, technology and agriculture experts including farmers are needed. There are rapid advances in information and communication technology, precision agriculture and data analytics, which are creating a fertile field for the creation of smart connected farms (SCF) and networked farmers. A network and coordinated farmer network provides unique advantages to farmers to enhance farm production and profitability, while tackling adverse climate events. The aim of this article is to provide a comprehensive overview of the state of the art in SCF including the advances in engineering, computer sciences, data sciences, social sciences and economics including data privacy, sharing and technology adoption.

In this article, we follow the framework given in the article {\it Physica A}, \textbf{158}, pg 58-63 (1989) by R. Laflamme to derive the thermofield double state for a causal diamond using the Euclidean path integral formalism, and subsequently derive the causal diamond temperature. The interpretation of the physical and fictitious system in the thermofield double state arises naturally from the boundary conditions of the fields defined on the Euclidean sections of the cylindrical background geometry $S^{1}_{\beta}\times \mathbb{R}$, where $\beta$ defines the periodicity of the Euclidean time coordinate and $S^{1}_{\beta}$ is a circumference of length $\beta$. The temperature detected by a static diamond observer at $x=0$ matches with the thermofield double temperature derived via this path integral procedure., Comment: 14 pages, 6 figures

For robots to seamlessly interact with humans, we first need to make sure that humans and robots understand one another. Diverse algorithms have been developed to enable robots to learn from humans (i.e., transferring information from humans to robots). In parallel, visual, haptic, and auditory communication interfaces have been designed to convey the robot's internal state to the human (i.e., transferring information from robots to humans). Prior research often separates these two directions of information transfer, and focuses primarily on either learning algorithms or communication interfaces. By contrast, in this review we take an interdisciplinary approach to identify common themes and emerging trends that close the loop between learning and communication. Specifically, we survey state-of-the-art methods and outcomes for communicating a robot's learning back to the human teacher during human-robot interaction. This discussion connects human-in-the-loop learning methods and explainable robot learning with multi-modal feedback systems and measures of human-robot interaction. We find that -- when learning and communication are developed together -- the resulting closed-loop system can lead to improved human teaching, increased human trust, and human-robot co-adaptation. The paper includes a perspective on several of the interdisciplinary research themes and open questions that could advance how future robots communicate their learning to everyday operators. Finally, we implement a selection of the reviewed methods in a case study where participants kinesthetically teach a robot arm. This case study documents and tests an integrated approach for learning in ways that can be communicated, conveying this learning across multi-modal interfaces, and measuring the resulting changes in human and robot behavior. See videos of our case study here: https://youtu.be/EXfQctqFzWs