Paul Richmond, Constantinos Papageorgakis, Vasilis Niarchos
et al.
We present specialized large language models (LLMs) for theoretical high-energy physics, obtained as 20 fine-tuned variants of the 8 billion parameter Llama-3.1 model. Each variant was trained on arXiv abstracts (through August 2024) from different combinations of hep-th, hep-ph and gr-qc. For a comparative study, we also trained models on datasets that contained abstracts from disparate fields such as the q-bio and cs categories. All models were fine-tuned using two distinct low-rank adaptation fine-tuning approaches and varying dataset sizes, and outperformed the base model on hep-th abstract completion tasks. We compare performance against leading commercial LLMs (ChatGPT, Claude, Gemini, DeepSeek) and derive insights for further developing specialized language models for high-energy theoretical physics.
The ExoClock project is an open platform aiming to monitor exoplanets by integrating observations from space- and ground-based telescopes. This study presents an updated catalog of 620 exoplanet ephemerides, integrating 30,000 measurements from ground-based telescopes (the ExoClock network), literature, and space telescopes (Kepler, K2 and TESS). The updated catalog includes 277 planets from TESS which require special observing strategies due to their shallow transits or bright host stars. This study demonstrates that data from larger telescopes, and the employment of new methodologies such as synchronous observations with small telescopes, are capable of monitoring special cases of planets. The new ephemerides show that 45% of the planets required an update while the results show an improvement of 1 order of magnitude in prediction uncertainty. The collective analysis also enabled the identification of new planets showing transit-timing variations, highlighting the importance of extensive observing coverage. Developed in the context of the ESA’s Ariel space mission, with the goal of delivering a catalog with reliable ephemerides to increase the mission efficiency, ExoClock’s scope and service have grown well beyond the remit of Ariel. The ExoClock project has been operating in the framework of open science, and all tools and products are accessible to everyone within academia and beyond, to support efficient scheduling of future exoplanet observations, especially from larger telescopes where the pressure for time allocation efficiency is higher (Ariel, JWST, VLT, ELT, Subaru etc.). The inclusion of diverse audiences in the process and the collaborative mode not only foster democratization of science but also enhance the quality of the results.
Ghaylen Triki, Mohammad Mohammadpour, Sousso Kelouwani
et al.
The integration of Autonomous Mobile Robots (AMRs) into smart manufacturing systems offers promising gains in flexibility and efficiency. However, navigating dynamic and constrained industrial environments remains challenging. AMRs often need to brake or stop abruptly to avoid collisions caused by unexpected changes or unforeseen nearby obstacles, which leads to high energy consumption and reduced operational efficiency. Unlike traditional methods that solely focus on safety, using priority rules or speed limits to avoid multi-robot deadlocks, our approach also considers energy efficiency and enables smooth navigation without imposing hierarchy among a fleet of robots. A hybrid framework is introduced that enables energy-aware and conflict-free path planning, enhancing long-term autonomy in AMR fleets. First, the decentralized AMR fleet operates autonomously while continuously reporting potential collision locations, along with the corresponding Time-To-Collision (TTC) values for unforeseen obstacles. Then, the data collected from the fleet is consolidated by a map coordinator unit, which introduces a novel obstacle persistence evaluation method. This method leverages Exponentially Weighted Moving Average (EWMA) modeling to distinguish between temporary and persistent obstacles. Next, to prevent multi-robot deadlocks, we propose a smart zoning framework based on energy and reachability analysis. Finally, an adaptive path planning algorithm is employed, using the updated multi-layered costmap to balance between path length and conflict cost, adapting to spatiotemporal variations in high-traffic locations. Through comparisons with several state-of-the-art algorithms, we demonstrate that the proposed method ensures safe navigation while achieving smoother trajectory execution and effective energy optimization in dynamic environments.
Abstract Anxiety and depression are significant concerns among antenatal women in Bangladesh. Despite the critical need for tailored mental health care in health facilities, studies on these symptoms in this demographic remain lacking. Therefore, our study aimed to assess the levels, distribution, and associated factors of depressive and anxiety symptoms and their co-occurrence among women seeking antenatal care at a public healthcare facility in Bangladesh. We conducted a cross-sectional study between May 2024, and June 2024, among women seeking antenatal care (ANC) care in Durgapur Upazila Health Complex, a primary-level public health facility in Bangladesh. Among 640 women who received ANC care, 638 participated in the study. Depressive symptoms were assessed by the Patient Health Questionnaire-9 (PHQ-9), and anxiety symptoms were assessed by the Generalized Anxiety Disorder-7 (GAD-7). Bivariate and multivariable logistic regression were conducted to determine factors contributing to depressive and anxiety symptoms. About 39% of participants had depressive symptoms and 50% had anxiety symptoms, with 26% experiencing both simultaneously. No participants had severe overall depressive or anxiety symptoms. PHQ-9 data indicated half experienced daily fatigue, while GAD-7 data showed over half experienced daily nervousness and two-fifths had daily fears. Women in the second and third trimesters had 43% (aOR: 0.57, 95% CI: 0.36–0.89) and 58% (aOR: 0.42, 95% CI: 0.24–0.71) lower odds of depressive symptoms compared to those in the first trimester respectively. Women with 11 years or more education had 40% (aOR: 0.60, 95% CI: 0.38–0.94) lower odds of anxiety. Additionally, women in the second and third trimesters had 40% (aOR: 0.60, 95% CI: 0.37–0.97) and 49% (aOR: 0.59, 95% CI: 0.29–0.91) lower likelihood of co-occurrence compared to those in the first trimester and women with 6–10 years of education had 48% (aOR: 0.52, 95% CI: 0.34–0.79) and those with 11 or more years had 52% (aOR: 0.48, 95% CI: 0.29–0.81) lower likelihood of co-occurring depressive and anxiety symptoms compared to women with 5 years or less education. Our study found a high prevalence of depressive and anxiety symptoms among antenatal care seekers, with notable co-occurrence of these conditions. Given these findings, there is an urgent need for targeted mental health support for these women, especially those in their first trimester and those with limited education.
Nathalie K. Jones, Jason J. Wang, Eric L. Nielsen
et al.
We present confirmation of HD 143811 AB b, a substellar companion to spectroscopic binary HD 143811 AB through direct imaging with the Gemini Planet Imager (GPI) and Keck NIRC2. HD 143811 AB was observed as a part of the GPI Exoplanet Survey in 2016 and 2019 and is a member of the Sco-Cen star formation region. The exoplanet is detected ∼430 mas from the host star by GPI. With two GPI epochs and one from Keck/NIRC2 in 2022, we confirm through common proper motion analysis that the object is bound to its host star. We derive an orbit with a semimajor axis of $6{4}_{-14}^{+32}$ au and eccentricity ${0.23}_{-0.16}^{+0.24}$ . Spectral analysis of the GPI H -band spectrum and NIRC2 L′ photometry provides additional proof that this object is a substellar companion. We compare the spectrum of HD 143811 AB b to PHOENIX stellar models and Exo-Radioactive-Convective Equilibrium Model (REM) exoplanet atmosphere models and find that Exo-REM models provide the best fits to the data. From the Exo-REM models, we derive an effective temperature of $104{2}_{-132}^{+178}$ K for the planet and translate the derived luminosity of the planet to a mass of 5.6 ± 1.1 M _Jup assuming hot-start evolutionary models. HD 143811 AB b is the first directly imaged planet around a binary that is not on an ultrawide orbit. Future characterization of this object will shed light on the formation of planets around binary star systems.
Abstract We discuss the notion of generating a cosmic inflation without any big bang singularity. It has recently been proved by Good and Linder ( arXiv:2503.02380 [gr-qc]) that such an expansion of the universe can be driven by quantum fluctuations embedded in vacuum. The rate of expansion is guided by a cosmological sum rule defined through the Schwarzian derivative. We explore the thermodynamic roots of Schwarzian and connect it with the surface gravity associated with an apparent horizon. In General Relativity the cosmological sum rule can be enforced only if the early universe is a Milne vacuum. We show that this restriction can be removed by considering an entropic source term in the Einstein–Hilbert action.
Astrophysics, Nuclear and particle physics. Atomic energy. Radioactivity
Deborah Neyrinck-Leglantier, Deborah Neyrinck-Leglantier, Deborah Neyrinck-Leglantier
et al.
IntroductionThe treatment of chronic viral infections can often bring viral replication under control. However, chronic immune activation persists and can lead to the development of comorbid conditions, such as cardiovascular disease and cancer. This is particularly true for people living with HIV (PLWH), who have significantly more extracellular vesicles from membrane budding, also called plasma microparticles (MPs), than healthy individuals (HDs), and a much more immunomodulatory phenotype. We hypothesized that the number and phenotypic heterogeneity of MPs can trigger a functional remodeling of immune responses in PLWH, preventing full immune restoration.MethodsWe investigated the rapid impact of three types of MPs — derived from membrane budding in platelets (CD41a+ PMPs), monocytes (CD14+ MMPs) and lymphocytes (CD3+ LMPs) in the plasma of PLWH or HDs—on four cell types (CD4+ and CD8+T lymphocytes, monocytes and DCs).ResultsThese investigations of the short multiple interactions and functions of MPs with these cells revealed an increase in the secretion of cytokines such as IFNg, IL2, IL6, IL12, IL17 and TNFa by the immune cells studied following interactions with MPs. We show that this functional remodeling of immune cells depends not only on the number, but also on the phenotype of MPs.ConclusionThese data suggest that the large numbers of MPs and their impact on functional remodeling in PLWH may be incompatible with the effective control of chronic infections, potentially leading to chronic immune activation and the onset of comorbid diseases.
Abstract In the present work, we have studied the effect of equation of state (EOS henceforth) parameter on the complexity of static, self-gravitating systems. Utilizing the notion of complexity of static, spherically symmetric stars in general relativity as defined by Herrera (Phys Rev D 97:044010, 2018), we have investigated four types of EOS parameters of anisotropic stellar models. The models under consideration are the: (i) Sharma et al. configuration ( arXiv:2402.05461 [gr-qc], 2024) assuming a linear EOS, (ii) Paul et al. compact object (Eur Phys J Plus 137:525, 2022) invoking a colour-flavour-locked EOS, (iii) Bhar anisotropic star (Astrophys Space Sci 359:41, 2015) employing a Chaplygin EOS and (iv) Sharma and Ratanpal stellar object (Int J Mod Phys D 22(13):1350074, 2013) assuming a quadratic EOS. All of these models share the Finch–Skea (FS) geometry for the interior spacetime. Our work shows that the complexity factor is strengthened as the EOS parameters increase for each of the equation of states under investigation.
Astrophysics, Nuclear and particle physics. Atomic energy. Radioactivity
Abstract Recently, an exact black hole solution in non-minimal Einstein–Yang–Mills theory was obtained, and its quasinormal modes were subsequently analyzed using the JWKB approximation (Gogoi and Ponglertsakul in Eur. Phys. J. C 84:652, 2024. https://doi.org/10.1140/epjc/s10052-024-12946-9 . arXiv:2402.06186 [gr-qc]). However, we demonstrate that this analysis lacks sufficient accuracy when studying modes with $$\ell \le n$$ ℓ ≤ n , where $$\ell $$ ℓ is the multipole number and n is the overtone number. To address this, we compute the quasinormal frequencies using the precise Leaver method. Our results show that while the fundamental mode deviates only slightly from the Schwarzschild value, the first few overtones exhibit significantly larger deviations, with the discrepancy growing rapidly with the overtone number. Moreover, beginning with the second overtone, we observe a striking phenomenon: the real part of the frequency tends to zero quickly as the non-minimal coupling constant increases. This combination of spectral stability in the fundamental mode and high sensitivity of the overtones suggests that the Yang–Mills contribution primarily deforms the metric in the near-horizon region, while the geometry quickly transitions back to a Schwarzschild-like form at larger radii. In addition, we compute the grey-body factors and confirm that they represent a more stable characteristic of the geometry, exhibiting a correspondence with quasinormal modes already at the first multipole. The Yang–Mills coupling enhances the grey-body factors, further increasing the transmission probability.
Astrophysics, Nuclear and particle physics. Atomic energy. Radioactivity
Abstract In recent works (M.D. Piano, S. Hohenegger, F. Sannino, Quantum black hole physics from the event horizon. Phys. Rev. D 109(2), 024045 (2024). https://doi.org/10.1103/PhysRevD.109.024045 . arXiv:2307.13489 [gr-qc], M.D. Piano, S. Hohenegger, F. Sannino, Effective metric descriptions of quantum black holes. Eur. Phys. J. C 84(12), 1273 (2024). https://doi.org/10.1140/epjc/s10052-024-13609-5 . arXiv:2403.12679 [gr-qc]), a framework has been developed to describe (quantum) deformed, spherically symmetric and static black holes in four dimensions. The key idea of this so-called Effective Metric Description (EMD) is to parametrise deformations of the classical Schwarzschild geometry by two functions that depend on a physical quantity and which are calculated in a self-consistent way as series expansions in the vicinity of the horizon. In this work we further strengthen this framework by first demonstrating that the corresponding series expansion coefficients can be completely and uniquely determined from measurements that are accessible for observers outside of the event horizon: we propose a Gedankenexperiment, consisting of probes following a free-falling trajectory that send signals to a stationary observer and show how an EMD can be constructed from suitable telemetric data. Furthermore, by linking the expansion coefficients of the EMD to the invariant eigenvalues of the energy momentum tensor, we determine a system of physical fields that provides an effective Einstein equation for the deformed black hole geometry. In the case of a simplified geometry and assuming that the metric deformations are small, we can write the leading order of the physical fields in a closed form in the metric functions. We illustrate our results at the example of the Hayward space-time.
Astrophysics, Nuclear and particle physics. Atomic energy. Radioactivity
Spectral gamma-ray analyses of washed and sieved cuttings using a Georadis RT-50 scintillation detector are obtained to calculate total GR. The resulting data is compared to well-log derived GR allowing to assess quality and representativeness of cutting samples. Three case studies utilizing legacy and new well-log and cutting data including crystalline basement have been performed to test the outcome. The results show that calculated GR from spectral cutting analyses exhibits the same API ranges than well-log derived GR both for legacy and recent wells. Two main mismatch types in data have been observed. The less significant one caused by small cavings either increasing or decreasing the calculated GR from spectral cutting analyses. The extent of the caving contamination can be identified thus allowing to define cutting samples where quantitative analyses are representative for a certain lithological interval. Strong data-mismatch between both GR curves observed in the case studies are either caused by contamination with lost circulation material (LCM) or caused by drilling activities (e.g. underreaming) that strongly impact cuttings quality. Such cuttings can be used for qualitative analyses only or require more work to be shifted to the respective well-log GR depth for quantitative analyses. Spectral GR from a recent well has been used in case study 2 for comparison with spectral composition obtained from cutting samples. Both methods deliver the same range of data values so spectral composition from cutting samples can be used to explain GR-readings in case no spectral well-log GR is available. Rock-typing schemes for crystalline basement lithologies based on spectral well-log GR have been reproduced with cutting-derived data in case study 3. Here it was possible to distinguish various rock type based on potassium contents. This enables to extent rock-typing schemes into wells without spectral GR.
It was recently claimed (arXiv:2405.05410 [gr-qc]) that evidence for a stochastic gravitational wave background observed by pulsar timing arrays can be attributed instead to random perturbations of the Sun's motion by transiting asteroids. I show that that this would lead to a large dipole component accompanying a much smaller quadrupolar perturbation of pulsar timing signals, which would not be confused with a gravitational wave signal. Such an anomalous dipole would have been detected and identified as a spurious background by the PTA collaborations, if it existed.
We report the detection of very high energy gamma-ray emission from the blazar S3 1227+25 (VER J1230+253) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). VERITAS observations of the source were triggered by the detection of a hard-spectrum GeV flare on 2015 May 15 with the Fermi-Large Area Telescope (LAT). A combined 5 hr VERITAS exposure on May 16 and 18 resulted in a strong 13 σ detection with a differential photon spectral index, Γ = 3.8 ± 0.4, and a flux level at 9% of the Crab Nebula above 120 GeV. This also triggered target-of-opportunity observations with Swift, optical photometry, polarimetry, and radio measurements, also presented in this work, in addition to the VERITAS and Fermi-LAT data. A temporal analysis of the gamma-ray flux during this period finds evidence of a shortest variability timescale of τ _obs = 6.2 ± 0.9 hr, indicating emission from compact regions within the jet, and the combined gamma-ray spectrum shows no strong evidence of a spectral cutoff. An investigation into correlations between the multiwavelength observations found evidence of optical and gamma-ray correlations, suggesting a single-zone model of emission. Finally, the multiwavelength spectral energy distribution is well described by a simple one-zone leptonic synchrotron self-Compton radiation model.
McKinley C. Brumback, Georgios Vasilopoulos, Joel B. Coley
et al.
Neutron star high-mass X-ray binaries with superorbital modulations in luminosity host warped inner accretion disks that occult the neutron star during precession. In SMC X-1, the instability in the warped disk geometry causes superorbital period “excursions”: times of instability when the superorbital period decreases from its typical value of 55 to ∼40 days. Disk instability makes SMC X-1 an ideal system in which to investigate the effects of variable disk geometry on the inner accretion flow. Using the high-resolution spectral and timing capabilities of the Neutron Star Interior Composition Explorer, we examined the high state of four different superorbital cycles of SMC X-1 to search for changes in spectral shape and connections to the unstable disk geometry. We performed pulse phase-averaged and phase-resolved spectroscopy to closely compare the changes in spectral shape and any cycle-to-cycle variations. While some parameters, including the photon index and absorbing column density, show slight variations with superorbital phase, these changes are most evident during the intermediate state of the superorbital cycle. Few spectral changes are observed within the high state of the superorbital cycle, possibly indicating the disk instability does not significantly change SMC X-1's accretion process.
Ben S. Prather, Jason Dexter, Monika Moscibrodzka
et al.
Interpretation of resolved polarized images of black holes by the Event Horizon Telescope (EHT) requires predictions of the polarized emission observable by an Earth-based instrument for a particular model of the black hole accretion system. Such predictions are generated by general relativistic radiative transfer (GRRT) codes, which integrate the equations of polarized radiative transfer in curved spacetime. A selection of ray-tracing GRRT codes used within the EHT Collaboration is evaluated for accuracy and consistency in producing a selection of test images, demonstrating that the various methods and implementations of radiative transfer calculations are highly consistent. When imaging an analytic accretion model, we find that all codes produce images similar within a pixel-wise normalized mean squared error (NMSE) of 0.012 in the worst case. When imaging a snapshot from a cell-based magnetohydrodynamic simulation, we find all test images to be similar within NMSEs of 0.02, 0.04, 0.04, and 0.12 in Stokes I , Q , U , and V , respectively. We additionally find the values of several image metrics relevant to published EHT results to be in agreement to much better precision than measurement uncertainties.
The present study aims to investigate the genomic variability and epidemiology of SARS-CoV-2 in Pakistan along with its role in the spread and severity of infection during the three waves of COVID-19. A total of 453 genomic sequences of Pakistani SARS-CoV-2 were retrieved from GISAID and subjected to MAFFT-based alignment and QC check which resulted in removal of 53 samples. The remaining 400 samples were subjected to Pangolin-based genomic lineage identification. And to infer our SARS-CoV-2 time-scaled and divergence phylogenetic trees, 3804 selected global reference sequences plus 400 Pakistani samples were used for the Nextstrain analysis with Wuhan/Hu-1/2019, as reference genome. Finally, maximum likelihood based phylogenetic tree was built by using the Nextstrain and coverage map was created by employing Nextclade. By using the amino acid substitutions, the maximum likelihood phylogenetic trees were developed for each wave, separately. Our results reveal the circulation of 29 lineages, belonging to following seven clades G, GH, GR, GRY, L, O, and S in the three waves. From first wave, 16 genomic lineages of SARS-CoV-2 were identified with B.1(24.7%), B.1.36(18.8%), and B.1.471(18.8%) as the most prevalent lineages respectively. The second wave data showed 18 lineages, 10 of which were overlapping with the first wave suggesting that those variants could not be contained during the first wave. In this wave, a new lineage, AE.4, was reported from Pakistan for the very first time in the world. However, B.1.36 (17.8%), B.1.36.31 (11.9%), B.1.1.7 (8.5%), and B.1.1.1 (5.9%) were the major lineages in second wave. Third wave data showed the presence of nine lineages with Alpha/B.1.1.7 (72.7%), Beta/B.1.351 (12.99%), and Delta/B.1.617.2 (10.39%) as the most predominant variants. It is suggested that these VOCs should be contained at the earliest in order to prevent any devastating outbreak of SARS-CoV-2 in the country.
Ciriaco Goddi, Iván Martí-Vidal, Hugo Messias
et al.
We present the results from a full polarization study carried out with the Atacama Large Millimeter/submillimeter Array (ALMA) during the first Very Long Baseline Interferometry (VLBI) campaign, which was conducted in 2017 April in the λ 3 mm and λ 1.3 mm bands, in concert with the Global mm-VLBI Array (GMVA) and the Event Horizon Telescope (EHT), respectively. We determine the polarization and Faraday properties of all VLBI targets, including Sgr A*, M87, and a dozen radio-loud active galactic nuclei (AGNs), in the two bands at several epochs in a time window of 10 days. We detect high linear polarization fractions (2%–15%) and large rotation measures (RM > 10 ^3.3 –10 ^5.5 rad m ^−2 ), confirming the trends of previous AGN studies at millimeter wavelengths. We find that blazars are more strongly polarized than other AGNs in the sample, while exhibiting (on average) order-of-magnitude lower RM values, consistent with the AGN viewing angle unification scheme. For Sgr A* we report a mean RM of (−4.2 ± 0.3) × 10 ^5 rad m ^−2 at 1.3 mm, consistent with measurements over the past decade and, for the first time, an RM of (–2.1 ± 0.1) × 10 ^5 rad m ^−2 at 3 mm, suggesting that about half of the Faraday rotation at 1.3 mm may occur between the 3 mm photosphere and the 1.3 mm source. We also report the first unambiguous measurement of RM toward the M87 nucleus at millimeter wavelengths, which undergoes significant changes in magnitude and sign reversals on a one year timescale, spanning the range from −1.2 to 0.3 × 10 ^5 rad m ^−2 at 3 mm and −4.1 to 1.5 × 10 ^5 rad m ^−2 at 1.3 mm. Given this time variability, we argue that, unlike the case of Sgr A*, the RM in M87 does not provide an accurate estimate of the mass accretion rate onto the black hole. We put forward a two-component model, comprised of a variable compact region and a static extended region, that can simultaneously explain the polarimetric properties observed by both the EHT (on horizon scales) and ALMA (which observes the combined emission from both components). These measurements provide critical constraints for the calibration, analysis, and interpretation of simultaneously obtained VLBI data with the EHT and GMVA.
Recently, an axially symmetric spacetime with causality violation is appeared in Ref. [1]. There, author presented a type III metric with vanishing expansion, shear and twist. The matter-energy represents a pure radial field with a negative cosmological constant. The spacetime is asymptotically anti-de Sitter space in the radial direction. Actually, this work with different for the metric was already published in Ref. [4]. Therefore, the current paper Ref. [1] is a duplicate one of the previous work.
We address the two issues raised by Bayle, Vallisneri, Babak, and Petiteau (in their gr-qc document arXiv:2106.03976) about our matrix formulation of Time-Delay Interferometry (TDI) (arXiv:2105.02054) \cite{TDJ21}. In so doing we explain and quantify our concerns about the results derived by Vallisneri, Bayle, Babak and Petiteau \cite{Vallisneri2020} by applying their data processing technique (named TDI-$\infty$) to the two heterodyne measurements made by a two-arm space-based GW interferometer. First we show that the solutions identified by the TDI-$\infty$ algorithm derived by Vallisneri, Bayle, Babak and Petiteau \cite{Vallisneri2020} {\underbar {do}} depend on the boundary-conditions selected for the two-way Doppler data. We prove this by adopting the (non-physical) boundary conditions used by Vallisneri {\it et al.} and deriving the corresponding analytic expression for a laser-noise-canceling combination. We show it to be characterized by a number of Doppler measurement terms that grows with the observation time and works for any time-dependent time delays. We then prove that, for a constant-arm-length interferometer whose two-way light times are equal to twice and three-times the sampling time, the solutions identified by TDI-$\infty$ are linear combinations of the TDI variable $X$. In the second part of this document we address the concern expressed by Bayle {\it et al.} regarding our matrix formulation of TDI when the two-way light-times are constant but not equal to integer multiples of the sampling time. We mathematically prove the homomorphism between the delay operators and their matrix representation \cite{TDJ21} holds in general. By sequentially applying two order-$m$ Fractional-Delay (FD) Lagrange filters of delays $l_1$, $l_2$ we find its result to be equal to applying an order-$m$ FD Lagrange filter of delay $l_1 + l_2$.