Search

New physics and astronomy faculty are excited about active teaching, but they still need support to implement the ideas in their classes. [ABSTRACT FROM AUTHOR]

Scheduled meetings are associated with standardization and understood as a bureaucratic form of coordination, control, and rule observation. In attending assemblies of a research team in optical physics for over a year, we found regular lab meetings are compulsory for all their members and are an avenue to announce and give information about new and changed institutional regulations, to supervise members' activities and their output. But more importantly, they offer an environment for continuous thinking through talk that goes beyond announcements. Meetings are a protected space to comment on conducted research, to amend experimental set-ups, to test argumentation, and to outline potentially new directions of research. By participating in these practices, researchers, become members of the team as they get acquainted with the ongoing research; its scope, problems, and limits; the solutions at hand; and the know-how within the team. In functional terms, observed internal meetings seem to (a) ensure that the research team focuses on a specific research agenda by talking about and discussing ongoing research in the lab, (b) be used to discuss and assure the quality of the team's research output, and (c) generate and inspire new research within the team. Our findings suggest regular internal meetings, like shop talk, are constitutive of doing science by talking about ongoing research. [ABSTRACT FROM AUTHOR]

Reactive-oxygen-species are produced more often in the body when bisphenol A (BPA), an endocrine-disrupting-substance, is present. In this investigation, bio-sorbents from an aqueous solution adapted from Aloe-vera were used to survey BPA removal. Aloe-vera leaf wastes were used to create activated carbon, which was then analyzed using Fourier transform infrared (FTIR), Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Zeta potential, and Brunauer-Emmett-Teller (BET) techniques. It was revealed that the adsorption process adheres to the Freundlich isotherm model with R2>0.96 and the pseudo-second-order kinetic model with R2>0.99 under ideal conditions (pH = 3, contact time = 45 min, concentration of BPA = 20 mg.L−1, and concentration of the adsorbent = 2 g.L−1). After five-cycle, the efficacy of removal was greater than 70%. The removal of phenolic-chemicals from industrial-effluent can be accomplished with the assistance of this adsorbent in a cost-effective and effective-approach. [ABSTRACT FROM AUTHOR]

Primordial abundances of light elements are sensitive to the physics of the early Universe and can directly constrain cosmological quantities, such as the baryon-to-photon ratio |$\eta _{10}$|⁠ , the baryon density, and the number of neutrino families. Deuterium is especially suited for these studies: its primordial abundance is sensitive and monotonically dependent on |$\eta _{10}$|⁠ , allowing an independent measurement of the cosmic baryon density that can be compared, for instance, against the Planck satellite data. The primordial deuterium abundance can be measured in high H  i column density absorption systems towards distant quasars. We report here a new measurement, based on high-resolution ESPRESSO data, of the primordial D  i abundance of a system at redshift |$z \sim 3.572$|⁠ , towards PKS1937-101. Using only ESPRESSO data, we find a D /H ratio of |$2.638\pm 10^{-5}$|⁠ , while including the available UVES data improves the precision, leading to a ratio of |$2.608 \pm 10^{-5}$|⁠. The results of this analysis agree with those of the most precise existing measurements. We find that the relatively low column density of this system (⁠|$\log {N_{\rm H_I}/ {\rm cm}^{-2}}\sim 18$|⁠) introduces modelling uncertainties, which become the main contributor to the error budget. [ABSTRACT FROM AUTHOR]

We report precise radial velocity (RV) observations of HD 212657 (= K2-167), a star shown by K2 to host a transiting sub-Neptune-sized planet in a 10 d orbit. Using Transiting Exoplanet Survey Satellite (TESS) photometry, we refined the planet parameters, especially the orbital period. We collected 74 precise RVs with the HARPS-N spectrograph between August 2015 and October 2016. Although this planet was first found to transit in 2015 and validated in 2018, excess RV scatter originally limited mass measurements. Here, we measure a mass by taking advantage of reductions in scatter from updates to the HARPS-N Data Reduction System (2.3.5) and our new activity mitigation method called CCF Activity Linear Model (CALM), which uses activity-induced line shape changes in the spectra without requiring timing information. Using the CALM framework, we performed a joint fit with RVs and transits using exofast v2 and find Mp  = |$6.3_{-1.4}^{+1.4}$|   |$\, M_{\hbox{$\oplus $}}$| and Rp  = |$2.33^{+0.17}_{-0.15}$|   |$\, R_{\hbox{$\oplus $}}$|⁠ , which places K2-167 b at the upper edge of the radius valley. We also find hints of a secondary companion at a ∼22 d period, but confirmation requires additional RVs. Although characterizing lower mass planets like K2-167 b is often impeded by stellar variability, these systems especially help probe the formation physics (i.e. photoevaporation, core-powered mass-loss) of the radius valley. In the future, CALM or similar techniques could be widely applied to FGK-type stars, help characterize a population of exoplanets surrounding the radius valley, and further our understanding of their formation. [ABSTRACT FROM AUTHOR]

In Cardiovascular Rehabilitation (CR), patient adherence to the maintenance phase is a major challenge. Virtual reality-based therapy (VRBT) promotes acute hemodynamic and autonomic repercussions similar to traditional rehabilitation and can increase patient adherence to the program. However, it is unknown whether the combination of VRBT to a traditional CR manages to maintain or even improve clinical and autonomic variables in long term. To analyze whether VRBT combination in a traditional CR can maintain or improve clinical and autonomic variables in cardiac patients in the maintenance phase of these programs. Twenty-six volunteers (62.04 ± 12.22 years) were evaluated, who underwent an initial assessment and two other assessments (in the sixth and 12th week) of the following outcomes: systolic and diastolic blood pressure, respiratory rate, pulse saturation of oxygen, heart rate, perceived exertion, and cardiac autonomic modulation, using linear and non-linear heart rate variability methods. Except for the apparent lack of clinical significance observed in Shannon Entropy, LF (nu), and HF (nu), the combination of VRBT as routine in a traditional program did not cause significant changes in the analyzed variables. combination of VRBT was able to maintain the chronic hemodynamic and autonomic repercussions caused by traditional CR. [ABSTRACT FROM AUTHOR]

This year, Aristotle readers could purchase something old and something new for their libraries. The old thing is Diana Quarantotto's edited volume on Aristotle's Physics I, published in 2018 but now finally available in paperback at an affordable price. People will remember that this book includes excellent commentaries on each chapter of Physics , like those by Andrea Falcon, Timothy Clarke, Laura M. Castelli, Lindsay Judson, David Charles, and Isván Bodnár, to name a few. The volume also contains a preface, an illuminating methodological introduction, and a collaborative translation of Aristotle's text. The main takeaway is a balanced appraisal of the importance of Physics I and its introductory role within Aristotle's physical project. [ABSTRACT FROM AUTHOR]

This work seeks to improve upon an existing formulation of the Method of Characteristics (MOC) with a Linear Source Approximation (LSA) for problems that use nonconstant cross sections like multiphysics feedback and the two-dimensional/one-dimensional (2D/1D) formulation. The previous LSA formulation for lattice physics calculations uses precomputed coefficients that are dependent on the multigroup total or transport cross sections, and the method can be demonstrated to lack robustness when there are negative sources. In this paper, the method is reformulated to eliminate the cross-section dependence of the precomputed coefficients without adding additional operations, and a more robust formulation is also developed to prevent the calculation of negative sources. Thus, the method has increased efficiency and robustness in multiphysics and 2D/1D simulations. The new method is implemented in the MPACT code and tested on several light water reactor problems. The numerical results show that with the new Linear Source formulation, the number of mesh elements can be significantly reduced while maintaining accuracy, resulting in reduced run time and memory usage. Furthermore, our results demonstrate improved efficiency for cases with depletion, thermal-hydraulic feedback, and in three-dimensional (2D/1D) calculations without any robustness issues. [ABSTRACT FROM AUTHOR]

Deep neural network (DNN) potentials have recently gained popularity in computer simulations of a wide range of molecular systems, from liquids to materials. In this study, we explore the possibility of combining the computational efficiency of the DeePMD framework and the demonstrated accuracy of the MB-pol data-driven, many-body potential to train a DNN potential for large-scale simulations of water across its phase diagram. We find that the DNN potential is able to reliably reproduce the MB-pol results for liquid water, but provides a less accurate description of the vapor–liquid equilibrium properties. This shortcoming is traced back to the inability of the DNN potential to correctly represent many-body interactions. An attempt to explicitly include information about many-body effects results in a new DNN potential that exhibits the opposite performance, being able to correctly reproduce the MB-pol vapor–liquid equilibrium properties, but losing accuracy in the description of the liquid properties. These results suggest that DeePMD-based DNN potentials are not able to correctly "learn" and, consequently, represent many-body interactions, which implies that DNN potentials may have limited ability to predict the properties for state points that are not explicitly included in the training process. The computational efficiency of the DeePMD framework can still be exploited to train DNN potentials on data-driven many-body potentials, which can thus enable large-scale, "chemically accurate" simulations of various molecular systems, with the caveat that the target state points must have been adequately sampled by the reference data-driven many-body potential in order to guarantee a faithful representation of the associated properties. [ABSTRACT FROM AUTHOR]

The elasticity of disordered and polydisperse polymer networks is a fundamental problem of soft matter physics that is still open. Here, we self-assemble polymer networks via simulations of a mixture of bivalent and tri- or tetravalent patchy particles, which result in an exponential strand length distribution analogous to that of experimental randomly cross-linked systems. After assembly, the network connectivity and topology are frozen and the resulting system is characterized. We find that the fractal structure of the network depends on the number density at which the assembly has been carried out, but that systems with the same mean valence and same assembly density have the same structural properties. Moreover, we compute the long-time limit of the mean-squared displacement, also known as the (squared) localization length, of the cross-links and of the middle monomers of the strands, showing that the dynamics of long strands is well described by the tube model. Finally, we find a relation connecting these two localization lengths at high density and connect the cross-link localization length to the shear modulus of the system. [ABSTRACT FROM AUTHOR]

Droplet impact dynamics is an interfacial phenomenon that is shown everywhere in nature and is the underlying of numerous technological applications including bio-printing, tissue engineering, pharmaceuticals, fight against COVID-19 pandemic, smart biomaterials, and flexible electronics. Over the last decade, expeditious advancement of novel functional interfacial surfaces, high-speed visualization, nanoscience, nanotechnology, machine learning, and computational power, as well as the connection of flow physics with interfacial science, have contributed to enhancing the understanding of relevant complex physical phenomena. Droplet, upon impacting onto substrates, can deposit, spread, bounce, and splash. Features of droplet impact physics and surface wettability necessitate elaborate solid–liquid interactions. Given the significance of droplet impact physics for healthcare and electronics, it is recommended for the scientific community to direct research studies to profound the understanding of such complex physics. Therefore, this Review initially focuses on liquid–solid interfacial science. Second, droplet impact physics on numerous solid surfaces was discussed. Substrates with various wettability and physical features were considered: hydrophilic, hydrophobic, superhydrophobic, smooth, rough, and flexible elastic surfaces. Furthermore, numerous advancements of droplet impact on solid surfaces related to advanced technologies and challenges including printed electronics, smart biomaterials, tissue engineering, machine learning, and COVID-19 pandemic were reviewed. Finally, this Review outlines future perspectives and research directions in complex droplet impact physics. [ABSTRACT FROM AUTHOR]

Simulations of water near extended hydrophobic spherical solutes have revealed the presence of a region of depleted density and accompanying enhanced density fluctuations. The physical origin of both phenomena has remained somewhat obscure. We investigate these effects employing a mesoscopic binding potential analysis, classical density functional theory (DFT) calculations for a simple Lennard-Jones solvent, and Grand Canonical Monte Carlo (GCMC) simulations of a monatomic water (mw) model. We argue that the density depletion and enhanced fluctuations are near-critical phenomena. Specifically, we show that they can be viewed as remnants of the critical drying surface phase transition that occurs at bulk liquid–vapor coexistence in the macroscopic planar limit, i.e., as the solute radius Rs → ∞. Focusing on the radial density profile ρ(r) and a sensitive spatial measure of fluctuations, the local compressibility profile χ(r), our binding potential analysis provides explicit predictions for the manner in which the key features of ρ(r) and χ(r) scale with Rs, the strength of solute–water attraction ɛsf, and the deviation from liquid–vapor coexistence of the chemical potential, δμ. These scaling predictions are confirmed by our DFT calculations and GCMC simulations. As such, our theory provides a firm basis for understanding the physics of hydrophobic solvation. [ABSTRACT FROM AUTHOR]

Light-induced orientation of gas phase molecules is a long-pursued goal in physics and chemistry. Here, we experimentally demonstrate a six-fold increase in the terahertz-induced orientation of iodomethane (CH3I) molecules at room temperature, provided by rotational pre-excitation with a moderately intense near-IR pulse. The paper highlights the underlying interference of multiple coherent transition pathways within the rotational coherence manifold and is analyzed accordingly. Our experimental and theoretical results provide desirable and practical means for all-optical experiments on oriented molecular ensembles. [ABSTRACT FROM AUTHOR]

The use of fully or partially absorbing boundary conditions for diffusion-based problems has become paradigmatic in physical chemistry and biochemistry to describe reactions occurring in solutions or in living media. However, as chemical states may indeed disappear, particles cannot, unless such degradation happens physically and should, thus, be accounted for explicitly. Here, we introduce a simple, yet general idea that allows one to derive the appropriate boundary conditions self-consistently from the chemical reaction scheme and the geometry of the physical reaction boundaries. As an illustration, we consider two paradigmatic examples, where the known results are recovered by taking specific physical limits. More generally, we demonstrate that our mathematical analysis delivers physical insight that cannot be accessed through standard treatments. [ABSTRACT FROM AUTHOR]

Non-Hermitian Hamiltonians provide an alternative perspective on the dynamics of quantum and classical systems coupled non-conservatively to an environment. Once primarily an interest of mathematical physicists, the theory of non-Hermitian Hamiltonians has solidified and expanded to describe various physically observable phenomena in optical, photonic, and condensed matter systems. Self-consistent descriptions of quantum mechanics based on non-Hermitian Hamiltonians have been developed and continue to be refined. In particular, non-Hermitian frameworks to describe magnonic and hybrid magnonic systems have gained popularity and utility in recent years with new insights into the magnon topology, transport properties, and phase transitions coming into view. Magnonic systems are in many ways a natural platform in which to realize non-Hermitian physics because they are always coupled to a surrounding environment and exhibit lossy dynamics. In this Perspective, we review recent progress in non-Hermitian frameworks to describe magnonic and hybrid magnonic systems, such as cavity magnonic systems and magnon–qubit coupling schemes. We discuss progress in understanding the dynamics of inherently lossy magnetic systems as well as systems with gain induced by externally applied spin currents. We enumerate phenomena observed in both purely magnonic and hybrid magnonic systems which can be understood through the lens of non-Hermitian physics, such as P T and anti- P T -symmetry breaking, dynamical magnetic phase transitions, non-Hermitian skin effect, and the realization of exceptional points and surfaces. Finally, we comment on some open problems in the field and discuss areas for further exploration. [ABSTRACT FROM AUTHOR]

In systems with frustration, the critical slowing down of the dynamics severely impedes the numerical study of phase transitions for even the simplest of lattice models. In order to help sidestep the gelation-like sluggishness, a clearer understanding of the underlying physics is needed. Here, we first obtain generic insight into that phenomenon by studying one-dimensional and Bethe lattice versions of a schematic frustrated model, the axial next-nearest neighbor Ising (ANNNI) model. Based on these findings, we formulate two cluster algorithms that speed up the simulations of the ANNNI model on a 2D square lattice. Although these schemes do not eliminate the critical slowing own, speed-ups of factors up to 40 are achieved in some regimes. [ABSTRACT FROM AUTHOR]

Coherence can drive wave-like motion of electrons and nuclei in photoexcited systems, which can yield fast and efficient ways to exert materials' functionalities beyond the thermodynamic limit. The search for coherent phenomena has been a central topic in chemical physics although their direct characterization is often elusive. Here, we highlight recent advances in time-resolved x-ray absorption spectroscopy (tr-XAS) to investigate coherent phenomena, especially those that utilize the eminent light source of isolated attosecond pulses. The unparalleled time and state sensitivities of tr-XAS in tandem with the unique element specificity render the method suitable to study valence electronic dynamics in a wide variety of materials. The latest studies have demonstrated the capabilities of tr-XAS to characterize coupled electronic–structural coherence in small molecules and coherent light–matter interactions of core-excited excitons in solids. We address current opportunities and challenges in the exploration of coherent phenomena, with potential applications for energy- and bio-related systems, potential crossings, strongly driven solids, and quantum materials. With the ongoing developments in both theory and light sources, tr-XAS holds great promise for revealing the role of coherences in chemical dynamics. [ABSTRACT FROM AUTHOR]

In this paper we review the possible mechanisms for the production of primordial black holes (PBHs) during a slow-reheating period in which the energy transfer of the inflaton field to standard model particles becomes effective at slow temperatures, offering a comprehensive examination of the theoretical foundations and conditions required for each of formation channel. In particular, we focus on post-inflationary scenarios where there are no self-resonances and the reheating epoch can be described by the inflaton evolving in a quadratic-like potential. In the hydrodynamical interpretation of this field during the slow-reheating epoch, the gravitational collapse of primordial fluctuations is subject to conditions on their sphericity, limits on their spin, as well as a maximum velocity dispersion. We show how to account for all conditions and show that PBHs form with different masses depending on the collapse mechanism. Finally we show, through an example, how PBH production serves to probe both the physics after primordial inflation, as well as the primordial powerspectrum at the smallest scales. [ABSTRACT FROM AUTHOR]

The cornea is one of the most commonly transplanted tissues worldwide. It is used to restore vision when severe visual impairment or blindness occurs in patients with corneal diseases or after trauma. Due to the global shortage of healthy donor corneas, decellularized corneal tissue has significant potential as an alternative to corneal transplantation. It preserves the native and biological ultrastructure of the cornea and, therefore, represents the most promising scaffold. This article discusses different methods of corneal decellularization based on the current literature. We searched PubMed.gov for articles from January 2009 to December 2023 using the following keywords: corneal decellularization, decellularization methods, and corneal transplantation. Although several methods of decellularization of corneal tissue have been reported, a universal standardised protocol of corneal decellularization has not yet been introduced. In general, a combination of decellularization methods has been used for efficient decellularization while preserving the optimal properties of the corneal tissue. [ABSTRACT FROM AUTHOR]

Purpose: An efficient physics-informed deep learning approach for extracting spinopelvic measures from X-ray images is introduced and its performance is evaluated against manual annotations. Methods: Two datasets, comprising a total of 1470 images, were collected to evaluate the model's performance. We propose a novel method of detecting landmarks as objects, incorporating their relationships as constraints (LanDet). Using this approach, we trained our deep learning model to extract five spine and pelvis measures: Sacrum Slope (SS), Pelvic Tilt (PT), Pelvic Incidence (PI), Lumbar Lordosis (LL), and Sagittal Vertical Axis (SVA). The results were compared to manually labelled test dataset (GT) as well as measures annotated separately by three surgeons. Results: The LanDet model was evaluated on the two datasets separately and on an extended dataset combining both. The final accuracy for each measure is reported in terms of Mean Absolute Error (MAE), Standard Deviation (SD), and R Pearson correlation coefficient as follows: [ S S ∘ : 3.7 (2.7) , R = 0.89 ] , [ P T ∘ : 1.3 (1.1) , R = 0.98 ] , [ P I ∘ : 4.2 (3.1) , R = 0.93 ] , [ L L ∘ : 5.1 (6.4) , R = 0.83 ] , [ S V A (m m) : 2.1 (1.9) , R = 0.96 ] . To assess model reliability and compare it against surgeons, the intraclass correlation coefficient (ICC) metric is used. The model demonstrated better consistency with surgeons with all values over 0.88 compared to what was previously reported in the literature. Conclusion: The LanDet model exhibits competitive performance compared to existing literature. The effectiveness of the physics-informed constraint method, utilized in our landmark detection as object algorithm, is highlighted. Furthermore, we addressed the limitations of heatmap-based methods for anatomical landmark detection and tackled issues related to mis-identifying of similar or adjacent landmarks instead of intended landmark using this novel approach. [ABSTRACT FROM AUTHOR]

This document is a preface to a special issue of the Journal of Materials Science titled "The Physics of Metal Plasticity." The preface acknowledges the complexity of plastic deformation in solids, particularly in metals, and the challenges in understanding the underlying mechanisms. It pays tribute to Professor Hussein M. Zbib, a respected researcher in the field of solid mechanics, who passed away in 2020. The special issue features 27 contributions that explore various aspects of plastic deformation across different length and time scales, using modeling, simulation, and testing methodologies. The contributions cover topics such as atomistic simulations, dislocation dynamics, continuum modeling, and the mechanical response of polymeric materials. The document also mentions the use of mechanical testing and microscopic characterization in studying the mechanical behavior of materials. [Extracted from the article]

Incubation, the process of successfully transferring the content of an egg into a living day old chick, and it is difficult to even imagine the complexity of the processes that are required inside of the egg to make it happen. However, the success of incubation is, next to the quality of the hatching egg to start with, highly determined by our ability to create the required climatic conditions around the eggs. To be able to successfully incubate, we have to first of all understand the requirements of the embryo, and then design, set and operate our machines in a way that meets the requirements of the embryo in the most adequate way. To create this optimum environment around the egg, we have to understand the physics that are involved in the process, as physics will determine the environment in the machines. To understand the requirements of the embryo, in theory we can simply look at the way mother hen does her incubation. With her millions of years of experience, she without any question will know the best what the embryo requires. However, this not necessarily guide us in the way to develop and set the machines, as she uses some different methods to create those conditions compared to our machines with many thousands of eggs. Within our machines, several factors are interacting with each other that are determining the outcome in a way that mother hen doesn't have to worry about. But nevertheless, we can learn some important lessons from her, especially lessons about the importance of conditions for the embryo versus importance of factors that are involved in an adequate functioning of the machines. If we look at the way mother hen incubates her eggs, it is clear that she only cares about temperature and turning. She doesn't even care about storage conditions, as the first egg from a clutch of 10 eggs will have to wait at least 10 days before she decides that incubation will start, and in that period she doesn't control conditions like storage temperature or humidity. But once incubation starts, she focusses on keeping the temperature on the required level and turning the eggs on a regular base. In fact, its not only mother hen that regulates the temperature, also the embryo plays an active role by directing more or less blood towards the cooler nest side of the egg (TZSCHENTKE and RUMPF, 2011), in that way finetuning the temperature inside of the egg. But mother hen doesn't control factors that are important in our process of artificial incubation like relative humidity (RH) and carbon dioxide (CO2). This suggests that controlling RH and CO might have more relation with the functioning of the machines than with the requirements of the embryo by itself (MEIJERHOF, 2009; OWEN, 1991). [ABSTRACT FROM AUTHOR]

This document is an editorial that highlights the significance of polymer processing techniques in the production of polymer components. It emphasizes the importance of using advanced modeling codes and experimental work to optimize polymer processing. The editorial presents several cutting-edge papers that contribute to the numerical, theoretical, and experimental knowledge of polymer physics. These papers cover a range of topics, including numerical methods for fluid flow simulations, non-Newtonian fluid mixing, molecular dynamics simulations of DNA polymers, theoretical models for polystyrene behavior, analytical solutions for polymer fluid flows, experimental investigations on drag-reducing polymers, characterization of thin films for energy storage, fabrication of cellulose nanocrystal-based materials, dynamic crushing performance of expanded polyethylene, and the influence of polycarboxylate ether superplasticizers on concrete behavior. The editorial concludes by stating that it serves as a valuable reference for researchers interested in staying updated on cutting-edge technologies in polymer physics. [Extracted from the article]

Liquid droplets hanging from solid surfaces are commonplace, but their physics is complex. Examples include dew or raindrops hanging onto wires or droplets accumulating onto a cover placed over warm food or windshields. In these scenarios, determining the force of detachment is crucial to rationally design technologies. Despite much research, a quantitative theoretical framework for detachment force remains elusive. In response, we interrogated the elemental droplet–surface system via comprehensive laboratory and computational experiments. The results reveal that the Young–Laplace equation can be utilized to accurately predict the droplet detachment force. When challenged against experiments with liquids of varying properties and droplet sizes, detaching from smooth and microtextured surfaces of wetting and non-wetting chemical make-ups, the predictions were in an excellent quantitative agreement. This study advances the current understanding of droplet physics and will contribute to the rational development of technologies. Understanding the physics that govern the dynamics of liquid droplets and their interaction with solid surfaces is crucial for a range of industrial applications, from pesticides to solar cells. Here, the authors develop a framework based on the Young-Laplace equation, to predict the force required to detach a drop from flat and microstructured solid surfaces. [ABSTRACT FROM AUTHOR]

A ferroelectric domain-wall memory has dual functionalities, where the volatile interfacial domain nearby the electrode can function as an embedded selector in contrast to the nonvolatile domain within an inner cell for information storage. However, most of crossbar memories require independent adjustments of the onset voltage of the selector and the coercive voltage of the inner domains at the same node fabrication technology. Here, we fabricated a LiNbO3 mesa-like domain-wall device to touch two top-to-top triangular-like Cu side electrodes. The readout wall current is more than 40 μA in write time as short as 20 ns. With the reduction of the apex angle of the Cu electrode from 180° to 30°, the onset voltage increases continuously from 0.68 to 3.05 V irrespective of the coercive voltage along with the improvement of polarization retention. The underlying physics is discussed on thickening of an effective interfacial layer projected along the applied electric-field direction. This finding enables the crossbar connection of high-density ferroelectric domain-wall memory. [ABSTRACT FROM AUTHOR]

Liquid droplets hanging from solid surfaces are commonplace, but their physics is complex. Examples include dew or raindrops hanging onto wires or droplets accumulating onto a cover placed over warm food or windshields. In these scenarios, determining the force of detachment is crucial to rationally design technologies. Despite much research, a quantitative theoretical framework for detachment force remains elusive. In response, we interrogated the elemental droplet–surface system via comprehensive laboratory and computational experiments. The results reveal that the Young–Laplace equation can be utilized to accurately predict the droplet detachment force. When challenged against experiments with liquids of varying properties and droplet sizes, detaching from smooth and microtextured surfaces of wetting and non-wetting chemical make-ups, the predictions were in an excellent quantitative agreement. This study advances the current understanding of droplet physics and will contribute to the rational development of technologies. Understanding the physics that govern the dynamics of liquid droplets and their interaction with solid surfaces is crucial for a range of industrial applications, from pesticides to solar cells. Here, the authors develop a framework based on the Young-Laplace equation, to predict the force required to detach a drop from flat and microstructured solid surfaces. [ABSTRACT FROM AUTHOR]

Recent observations of nontrivial spin textures and topological Hall effect (THE) in 2D van der Waals (vdW) ferromagnets have stimulated high interest in both fundamental physics and prospective spintronic applications. However, effectively manipulating spin textures and their exhibiting THE, which is the prerequisite for topology‐based 2D vdW devices, remains challenging. Here, the effective manipulation of the magnetic bubbles and THE is achieved in Fe5GeTe2 (FGT) crystals by utilizing Lorentz imaging and electrical transport measurements. The density and size of magnetic bubbles can be modulated effectively as the temperature and lamella thickness change, indicating the role of magnetocrystalline anisotropy and long‐range magnetic dipolar interaction is demonstrated, respectively. More importantly, the spin configurations of bubbles along with THE signal vary with sample thickness, demonstrating a topological transition between skyrmion bubbles and trivial bubbles. The key point lies in the presence or absence of Bloch lines in the stripe domain at different thicknesses. This study presents the reliable manipulations of spin textures and THE in FGT, which may provide valuable insights into the design of 2D vdW devices in spintronics. [ABSTRACT FROM AUTHOR]

This study introduces a novel method for enhancing Boiling Water Reactor (BWR) operation simulations by integrating machine learning (ML) models with conventional simulation techniques. The ML model is trained to identify and correct errors in low-fidelity simulation outputs, traditionally derived from core physics computations. These corrections aim to align the low-fidelity results closely with high-fidelity data. Precise predictions of nuclear reactor parameters like core eigenvalue and power distribution are crucial for efficient fuel management and adherence to technical specifications. Current high-fidelity transport calculations, while accurate, are impractical for real-time predictions due to extensive computational demands. Our approach, therefore, utilizes the standard two-step simulation process-assembly-level lattice physics calculations followed by whole-core nodal diffusion computations-to generate initial results, which are then refined using the ML-based error correction model. The methodology focuses on improving simulation accuracy in regular BWR operations rather than developing a universal ML predictor for reactor physics. By training an advanced neural network model on the difference in high-fidelity and low-fidelity simulations, the model can reduce the nodal power error from low-fidelity simulations to around 1% on average and the core eigenvalue down to under 100 pcm. This result is under the condition of the normal variations of control rod pattern and core flow rate changes in standard BWR operations used in the training and evaluation of the machine learning model. This work suggests a promising approach for achieving more accurate, computationally feasible simulation solutions in nuclear reactor operation and management. [ABSTRACT FROM AUTHOR]

We solve the problem of electron scattering at a potential temporal step discontinuity. For this purpose, instead of the Schrödinger equation, we use the Dirac equation, for access to back-scattering and relativistic solutions. We show that back-scattering, which is associated with gauge symmetry breaking, requires a vector potential, whereas a scalar potential induces only Aharonov–Bohm type energy transitions. We derive the scattering probabilities, which are found to be of later-forward and later-backward nature, with the later-backward wave being a relativistic effect, and compare the results with those for the spatial step and classical electromagnetic counterparts of the problem. Given the unrealizability of an infinitely sharp temporal discontinuity—which is of the same nature as its spatial counterpart!—we also provide solutions for a smooth potential step and demonstrate that the same physics as for the infinitely sharp case is obtained when the duration of the potential transition is sufficiently smaller than the de Broglie period of the electron (or deeply sub-period). [ABSTRACT FROM AUTHOR]

This work offers a didactical introduction to the calculations and geometrical properties of a static, spherically symmetric spacetime foliated by hyperboloidal time surfaces. We discuss the various degrees of freedom involved, namely the height function, responsible for introducing the hyperboloidal time coordinate, and a radial compactification function. A central outcome is the expression of the Trautman–Bondi mass in terms of the hyperboloidal metric functions. Moreover, we apply this formalism to a class of wave equations commonly used in black-hole perturbation theory. Additionally, we provide a comprehensive derivation of the hyperboloidal minimal gauge, introducing two alternative approaches within this conceptual framework: the in-out and out-in strategies. Specifically, we demonstrate that the height function in the in-out strategy follows from the well-known tortoise coordinate by changing the sign of the terms that become singular at future null infinity. Similarly, for the out-in strategy, a sign change also occurs in the tortoise coordinate's regular terms. We apply the methodology to the following spacetimes: Singularity-approaching slices in Schwarzschild, higher-dimensional black holes, black hole with matter halo, and Reissner–Nordström–de Sitter. From this heuristic study, we conjecture that the out-in strategy is best adapted for black hole geometries that account for environmental or effective quantum effects. This article is part of a discussion meeting issue 'At the interface of asymptotics, conformal methods and analysis in general relativity'. [ABSTRACT FROM AUTHOR]

A fateful decision as a 15-year-old high school student, and good advice from a distinguished professor of zoology, were the catalysts that not only decided my entire career but also led me to the Journal of Comparative Physiology A, and to the myriad biological wonders that were held within its covers. In my celebration of JCPA, I look back on the formative years of my career in Australia, and the crucial role that the journal played in shaping my emerging research interests, and ultimately my entire life. [ABSTRACT FROM AUTHOR]

To explore queer touch in digital spaces, the authors consider three games that sit uneasily within the genre of the first-person shooter (FPS), in which the player mediates gameplay through a first-person perspective, typically in the form of an armed individual. The FPS was fundamental in establishing such technological idiosyncrasies as real-time rendering and physics that still shape digital intimacy today. As these techniques were developed, a normative and often violent regime of touch was established whereby sight equated destructive, obliterating intimacy. Yet, as explored in this article, through techniques such as glitch, mechanical remixing, and code reappropriation, normative touch itself can be broken, giving way to queerer forms of intimacy. The authors center their analysis on Trespasser, Portal, and Polaris. Although disparate in content, production context, and temporality, all three games seek to reinterpret physical intimacy in code and narrative. [ABSTRACT FROM AUTHOR]

The study aims to examine the citation behaviour of Physics and Astronomy researchers from Indian central universities in the Western Himalayan region. By employing Bibliometrix and Biblioshiny packages in R Studio, an analysis of 13,065 cited sources was conducted using data from the Scopus database over a ten-year span (2012-2021). The findings highlight a preference for influential journal articles and reviews, with an inclination towards articles authored by two or three individuals. These findings offer valuable insights for stakeholders including researchers, policymakers, and funders, to enhance research impact in the region. The study also draws attention to 'undefined' tags in bibliographic data and calls for refinement in defining metadata to enhance bibliographic data quality and reliability. [ABSTRACT FROM AUTHOR]

It is important to recognize that each individual has a unique learning style and way of understanding concepts. Therefore, teaching must be able to adapt to students' needs and learning styles. In relation to learning models, Quantum Teaching is a learning model that creates a pleasant and conducive situation through various effective learning interactions during the learning process. In relation to learning models, Quantum Teaching is a learning model that creates a pleasant and conducive situation through various effective learning interactions during the learning process. The method used in this research is a quantitative Quasi Experiment with a nonequivalent control group design. Data collection in this research used post instruments. To obtain data on students' conceptual understanding, a test was used in the form of essay questions using Newton's Law. The results of the t test show that students' understanding was analyzed using an independent t-test with the assumption of equal variance, the significance value obtained was 0.007. The results of data analysis show that there is a significant increase in the understanding of physics concepts regarding Newton's laws in the experimental group that uses the Quantum Teaching model. [ABSTRACT FROM AUTHOR]

Thus studying physics is very important as it relates to real life. However, based on the results of a survey that has been carried out in a high school, it is known that student learning outcomes are less / low, this is due to difficulties in understanding fundamental physics concepts, limitations in solving physics problems, and lack of connections between these concepts. Therefore, the purpose of this study is to analyze how the implementation of the application of the PBL model for the learning outcomes of dynamic fluid material students. The method applied in this study is quantitative Quasi Experiment using nonequivalent control group design. From the results of research that has been carried out, it can be concluded that the PBL learning model has the potential to improve physical learning outcomes, especially in the context of Dynamic Fluid material. The implications of this research can be used as a basis to recommend the application of the Problem Based Learning model in physics learning to improve the effectiveness and efficiency of the concept understanding process at the relevant educational level. Further research can be conducted to explore specific aspects of this learning model that exert the most significant impact on understanding physics concepts. [ABSTRACT FROM AUTHOR]

PELICAN is a novel permutation equivariant and Lorentz invariant or covariant aggregator network designed to overcome common limitations found in architectures applied to particle physics problems. Compared to many approaches that use non-specialized architectures that neglect underlying physics principles and require very large numbers of parameters, PELICAN employs a fundamentally symmetry group-based architecture that demonstrates benefits in terms of reduced complexity, increased interpretability, and raw performance. We present a comprehensive study of the PELICAN algorithm architecture in the context of both tagging (classification) and reconstructing (regression) Lorentz-boosted top quarks, including the difficult task of specifically identifying and measuring the W-boson inside the dense environment of the Lorentz-boosted top-quark hadronic final state. We also extend the application of PELICAN to the tasks of identifying quark-initiated vs. gluon-initiated jets, and a multi-class identification across five separate target categories of jets. When tested on the standard task of Lorentz-boosted top-quark tagging, PELICAN outperforms existing competitors with much lower model complexity and high sample efficiency. On the less common and more complex task of 4-momentum regression, PELICAN also outperforms hand-crafted, non-machine learning algorithms. We discuss the implications of symmetry-restricted architectures for the wider field of machine learning for physics. [ABSTRACT FROM AUTHOR]

The recent observation of entanglement between top and anti-top quarks at the LHC opens the way to interpreting collider data with quantum information tools. In this work we investigate the relevance of quantum observables in searches of new physics. To this aim, we study spin correlations of pairs originating from various intermediate resonances, and compare the discovery reach of quantum observables compared to classical ones. We find that they provide complementary information and, in several notable cases, also the additional leverage necessary to detect new effects. [ABSTRACT FROM AUTHOR]

We present a comprehensive analysis of electroweak, flavor, and collider bounds on the complete set of dimension-six SMEFT operators in the U(2)5-symmetric limit. This operator basis provides a consistent framework to describe a wide class of new physics models and, in particular, the motivated class of models where the new degrees of freedom couple mostly to the third generation. By analyzing observables from all three sectors, and consistently including renormalization group evolution, we provide bounds on the effective scale of all 124 U(2)5-invariant operators. The relation between flavor-conserving and flavor-violating observables is analyzed taking into account the leading U(2)5 breaking in the Yukawa sector, which is responsible for heavy-light quark mixing. We show that under simple, motivated, and non-tuned hypotheses for the parametric size of the Wilson coefficients at the high scale, all present bounds are consistent with an effective scale as low as 1.5 TeV. We also show that a future circular e+e− collider program such as FCC-ee would push most of these bounds by an order of magnitude. This would rule out or provide clear evidence for a wide class of compelling new physics models that are fully compatible with present data. [ABSTRACT FROM AUTHOR]

Neutrino experiments, in the next years, aim to determine with precision all the six parameters of the three-neutrino standard paradigm. The complete success of the experimental program is, nevertheless, attached to the non-existence (or at least smallness) of Non-Standard Interactions (NSI). In this work, anticipating the data taken from long-baseline neutrino experiments, we map all the weakly coupled theories that could induce sizable NSI, with the potential to be determined in these experiments, in particular DUNE. Once present constraints from other experiments are taken into account, in particular charged-lepton flavor violation, we find that only models containing leptoquarks (scalar or vector) and/or neutral isosinglet vector bosons are viable. We provide the explicit matching formulas connecting weakly coupled models and NSI, both in propagation and production. Departing from the weakly coupled completion with masses at TeV scale, we also provide a global fit on all NSI for DUNE, finding that NSI smaller than 10−2 cannot be probed even in the best-case scenario. [ABSTRACT FROM AUTHOR]

The Standard Model of electroweak interactions is based on the fundamental SU(2)weak × U(1)elect representation. It assumes massless neutrinos and purely left-handed massive W ± and Z0 bosons to which one should add the massless photon. The existence, verified experimentally, of neutrino oscillations poses a challenge to this scheme, since the oscillations take place between at least three massive neutrinos belonging to a mass hierarchy still to be determined. One should also take into account the possible existence of sterile neutrino species. In a somehow different context, the fundamental nature of the strong interaction component of the forces in nature is described by the, until now, extremely successful representation based on the SU(3)strong group which, together with the confining rule, give a description of massive hadrons in terms of quarks and gluons. To this is added the minimal U(1) Higgs group to give mass to the otherwise massless generators. This representation may also be challenged by the existence of both dark matter and dark energy, of still unknown composition. In this note, we shall discuss a possible connection between these questions, namely the need to extend the SU(3)strong × SU(2)weak × U(1)elect to account for massive neutrinos and dark matter. The main point of it is related to the role of axions, as postulated by Roberto Peccei and Helen Quinn. The existence of neutral pseudo-scalar bosons, that is, the axions, has been proposed long ago by Peccei and Quinn to explain the suppression of the electric dipole moment of the neutron. The associated U(1)PQ symmetry breaks at very high energy, and it guarantees that the interaction of other particles with axions is very weak. We shall review the axion properties in connection with the apparently different contexts of neutrino and dark matter physics. [ABSTRACT FROM AUTHOR]

Chaotic dynamical systems often exhibit transient chaos, where trajectories behave chaotically for a short amount of time before escaping to an external attractor. Sustaining transient chaotic dynamics under disturbances is challenging yet desirable for many applications. The partial control approach exploits the inherent symmetry and geometric structure of chaotic saddles, the topological object responsible of transient chaos, to enable surprising control with only small perturbations. Here, we review the latest findings in partial control techniques with the aim to sustain chaos or accelerate escapes by exploiting these intricate invariant sets. We introduce the fundamental concept of safe sets regions where orbits persist despite noise. This paper presents recent generalizations through safety functions and escape functions that automatically find the minimum control needed. Efficient numerical algorithms are presented and several examples of application are illustrated. Rather than eliminating chaos entirely, partial control techniques provide a framework to reliably control transient chaotic dynamics with minimal interventions. This approach has promising applications across diverse fields including physics, engineering, biology, and more. [ABSTRACT FROM AUTHOR]