We compute the conservative scattering angle of two classical charged particles at the sixth order in electromagnetic coupling, and at the fourth order in velocity, thereby going beyond the current state of the art [fifth order in coupling, derived by Bern et al., Phys. Rev. Lett. 132, 251601 (2024)]. Our result is obtained by using the electromagnetic version of the effective one-body formalism to transfer information from the exact circular binary-charge solution of Schild [Phys. Rev. 131, 2762 (1963)] to the postLorentzian expansion of the scattering angle.

Starting from the recently derived conservative tail-of-tail action [High precision black hole scattering: Tutti Frutti vs worldline effective field theory, arXiv:2504.20204.] we compute several dynamical observables of binary systems (Delaunay Hamiltonian, scattering angle), at the 6.5 post-Newtonian accuracy and up to the eighth post-Minkowskian order. We find perfect agreement with previous self-force results, and (when inserting a recent high-post-Newtonian order derivation of radiated angular momentum [Scattering of a point mass by a Schwarzschild black hole: Radiated energy and angular momentum, arXiv:2507.03442.]) with state-of-the-art post-Minkowskian scattering results [Emergence of Calabi–Yau manifolds in high-precision black-hole scattering, Nature (London) 641, 603 (2025).].

After studying properties of the Nariai solution, including its geodesics, in spherical and de Sitter coordinates, two kinds of accelerated motion are investigated in detail: either observers at rest with respect to the coordinates, or observers in radial motion. Next, massless scalar perturbations of Nariai spacetime in absence of sources are worked out, and an explicit example out of the black hole context of analytic self-force calculation is obtained. Last, self-force effects are studied as well, together with some variant of the type of Poynting-Robertson external force, and also building a test electromagnetic field and a test gravitational field in Nariai spacetime geometry.

We consider black hole scattering up to the fifth post-Minkowskian (G5) order and compare the predictions of the tutti frutti formalism to the results obtained within two different versions of worldline effective field theory. At the G4 order we highlight the complete agreement between tutti frutti results and the results of [C. Dlapa et al., [Phys. Rev. Lett. 130, 101401 (2023)]], and show how the tutti frutti approach allows one to extract the O(G3) angular momentum loss from the O(G4) impulse. We compare the sixth post-Newtonian (6PN) accurate tutti frutti predictions to the recent results of [M. Driesse et al., [Nature 641, 603 (2025)]], which are at the G5 order, and at the leading order in the two mass ratios, finding complete agreement. We highlight that this agreement involves the presence at the 5.5PN level of a nonlocal tail-of-tail contribution to the scattering (first computed in [D. Bini et al., [Phys. Rev. D 102, 084047 (2020)]]), and involves, at the 6PN level, the presence of a O(G4) contribution to the angular momentum loss [C. Heissenberg, [Phys. Rev. D 111, 126012 (2025)]]. At the second order in the mass ratios of the O(G5) order we predict two independent gauge-invariant observables to high-PN accuracy.

This paper proves that, in a four-dimensional spherically symmetric spacetime manifold, one can consider coordinate transformations expressed by fractional linear maps which give rise to isometries and are the simplest example of coordinate transformation used to bring infinity down to a finite distance. The projective boundary of spherically symmetric spacetimes here studied is the disjoint union of three points: future timelike infinity, past timelike infinity, spacelike infinity, and the three-dimensional products of half-lines with a 2-sphere. Geodesics are then studied in the projectively transformed (t′,r′,θ′,φ′) coordinates for Schwarzschild spacetime, with special interest in their way of approaching our points at infinity. Next, Nariai, de Sitter and Gödel spacetimes are studied with our projective method. Since the kinds of infinity here defined depend only on the symmetry of interest in a spacetime manifold, they have a broad range of applications, which motivate the innovative analysis of Schwarzschild, Nariai, de Sitter and Gödel spacetimes.

We compute the next-to-leading-order radiation-reaction modification to the harmonic coordinate quasi- Keplerian parametrization of the binary dynamics, the two bodies undergoing a scattering process. The solution for the radiation-reaction corrections to the orbital parameters is examined both in the time domain (exact results) and in the frequency domain (results presented in the limit of large angular momentum, i.e., as a post-Minkowskian series expansion). The knowledge of the radiation-reaction corrected orbit is a key ingredient for the calculation of the fractional 3.5 post-Newtonian corrections to the radiative losses as well as to the radiative multipole moments needed to build up the waveform at the same accuracy.

We show that the null geodesic radial action for unbound orbits in the Kerr spacetime, and consequently the scattering angle, can be resummed in terms of hypergeometric functions, extending previous results [Ivanov et al., Resummation of universal tails in gravitational waveforms, arXiv:2504.07862.]. We provide explicit expressions as series expansions in powers of the Kerr rotational parameter up to the fourth order included.We finally use the Mano-Suzuki-Takasugi formalism to prove the relation between the renormalized angular momentum and the radial action highlighted in previous works.

We show that for a topological star the renormalized angular momentum parameter, ν, appearing in the Mano-Suzuki-Takasugi-type or in the quantum-Seiberg-Witten-type approaches of the perturbation equations, (1) has a direct link with the geodesic radial action computed along the null orbits of the background and (2) admits an exact resummation in terms of hypergeometric functions, generalizing previous results valid in the Schwarzschild case; see [M. M. Ivanov, Y. Z. Li, J. Parra-Martinez, and Z. Zhou, Resummation of universal tails in gravitational waveforms, arXiv:2504.07862.].

We compute the scattering angle for a scalar neutral probe undergoing unbound motion around a topological star, including self-force effects. Moreover, we identify the “electromagnetic” source of the background as a Papapetrou field compatible with the isometries and characterize topological stars by studying their sectional curvature, geometric transport along special curves, and gravitational energy content in terms of the superenergy tensors.

We analyze scalar wave emission from unbound orbits in a topological star spacetime. Our study uses a self-force approach and leads to a post-Newtonian reconstruction of the field along the orbit, both in the time domain and in the frequency domain. We also compute leading-order radiation losses, namely energy and angular momentum.

We study deviations from geodesic motions in a topological star spacetime for either massive, charged and spinning particles, elucidating different behaviors with the Schwarzschild spacetime. We also consider the deviations for the motion of electrically charged stringy probes in D = 5, framing all cases within a unified picture.

In this note, we show how the exploitation of the lattice momentum balance condition allows us to envisage an analytical procedure to define the lattice pressure tensor (LPT) for the multi-phase Shan–Chen (SC) lattice Boltzmann method (LBM) with single-range potential. This con- struction ensures that the LPT normal component to a flat interface is constant to machine precision on each lattice node, i.e., it exactly implements the mechanical equilibrium condition on the lattice. We demonstrate the robustness of the approach by providing analytical expressions for the coexistence curves for different choices of the pseudo-potential and forcing schemes in the SC-LBM. This paper offers a novel and rigorous perspective for controlling the LPT in the SC-LBM, paving the way for its application in more general settings.

Based on mesoscale lattice Boltzmann numerical simulations, we characterize the Rayleigh-Bénard (RB) convective dynamics of dispersions of liquid droplets in another liquid phase. Our numerical methodology allows us to modify the droplets’ interfacial properties to mimic the presence of an emulsifier (e.g., a surfactant), resulting in a positive disjoining pressure which stabilizes the droplets against coalescence. To appreciate the effects of this interfacial stabilization on the RB convective dynamics, we carry out a comparative study between a proper emulsion, i.e., a system where the stabilization mech- anism is present (stabilized liquid-liquid dispersion), and a system where the stabilization mechanism is absent (nonstabilized liquid-liquid dispersion). The study is conducted by systematically changing both the volume fraction φ and the Rayleigh number Ra. We find that the morphology of the two systems is dramatically different due to the different inter- facial properties. However, the two systems exhibit similar global heat transfer properties, expressed via the Nusselt number Nu. Significant differences in heat transfer emerge at smaller scales, which we analyze via the Nusselt number defined at mesoscales Numes. In particular, stabilized systems exhibit more intense mesoscale heat flux fluctuations due to the persistence of fluid velocity fluctuations down to small scales, which are instead dissipated in the interfacial dynamics of nonstabilized dispersions. For fixed Ra, the difference in mesoscale heat-flux fluctuations depends nontrivially on φ, featuring a maximum in the range 0.1 < φ < 0.2. Taken all together, our results highlight the role of interfacial physics in mesoscale convective heat transfer of complex fluids.

We develop a mesoscale computational model to describe the interaction of a droplet with a solid. The model is based on the hybrid combination of the immersed boundary and the lattice Boltzmann computational schemes: The former is used to model the nonideal sharp interface of the droplet coupled with the inner and outer fluids, simulated with the lattice Boltzmann scheme. We further introduce an interaction force to model the wetting interactions of the droplet with the solid at mesoscale: This interaction force is designed with the key computational advantage of providing a regularization of the interface profile close to the contact line, avoiding abrupt curvature changes that could otherwise cause numerical instabilities. The proposed model substantially improves earlier immersed boundary-lattice Boltzmann models for wetting in that it allows a description of an ample variety of wetting interactions, ranging from hydrophobic to hydrophilic cases, without the need for any precalibration study on model parameters to be used. Model validations against analytical results for droplet shape at equilibrium and scaling laws for droplet spreading dynamics are addressed.

Addressing complexity in the study of life sciences through Systems Biology and Systems Medicine has been transformative, making Systems Pharmacology the next logical step. In this review, we focus on physical stimuli, whose potential in pharmacology has been neglected, despite demonstrated therapeutic properties. To address this overlooked aspect of pharmacology, we aim to (i), highlight how physical stimuli (mechanical, optical, magnetic, electrical) influence inflammation; (ii) identify known overlaps among transduction mechanisms of physical stimuli and highlight the need for deeper understanding of these mechanisms; (iii) promote advanced network approaches as tools to understand this complexity and enhance the potential of anti-inflammatory physical therapies; and (iv), integrate physical stimuli into the mindset of pharmacologists. The overall purpose of this review is to spark questions rather than provide answers, and to drive research in this critically underexplored area.

Objectives: Cardiovascular diseases (CVDs) represent a major risk for people with type 1 diabetes (T1D). Our aim here is to develop a new methodology that overcomes some of the problems and limitations of existing risk calculators. First, they are rarely tailored to people with T1D and, in general, they do not deal with missing values for any risk factor. Moreover, they do not take into account information on risk factors dependencies, which is often available from medical experts. Method: This study introduces a Bayesian Belief Network (BBN) model to quantify CVD risk in individuals with T1D. The developed methodology is applied to a large T1D dataset and its performances are assessed. A simulation study is also carried out to quantify the parameter estimation properties. Results: The performances of individual risk estimation, as measured by the area under the ROC curve and by the C-index, are about 0.75 for both real and simulated data with comparable sample sizes. Conclusions: We observe a good predictive ability of the proposed methodology with accurate parameter estimation. The BBN approach takes into account causal relationships between variables, providing a comprehensive description of the system. This makes it possible to derive useful tools for optimising intervention.

Future occurrence of a disease can be highly influenced by some specific risk factors. This work presents a comprehensive approach to quantify the event probability as a function of each separate risk factor by means of a parametric model. The proposed methodology is mainly described and applied here in the case of a linear model, but the non-linear case is also addressed. To improve estimation accuracy, three distinct methods are developed and their results are integrated. One of them is Bayesian, based on a non-informative prior. Each of the other two, uses aggregation of sample elements based on their factor values, which is optimized by means of a different specific criterion. For one of these two, optimization is performed by Simulated Annealing. The methodology presented is applicable across various diseases but here we quantify the risk for cardiovascular diseases in subjects with type 1 diabetes. The results obtained combining the three different methods show accurate estimates of cardiovascular risk variation rates for the factors considered. Furthermore, the detection of a biological activation phenomenon for one of the factors is also illustrated. To quantify the performances of the proposed methodology and to compare them with those from a known method used for this type of models, a large simulation study is done, whose results are illustrated here.

We show that for a certain class of convex functions f, including the exponential functions x↦eλx with λ>0 a real number, and all the powers x↦xβ, x≥0 and β≥2 a real number, with a unique small exception, if (d1,...,dn) ranges over the degree sequences of graphs with n vertices and m edges and m≤n−1, then the maximum of ∑if(di) is uniquely attained by the degree sequence of a quasi-star graph, namely, a graph consisting of a star plus possibly additional isolated vertices. This result significantly extends a similar result in Ismailescu and Stefanica (2002). Dually, we show that for a certain class of concave functions g, including the negative exponential functions x↦1−e−λx with λ>ln(2) a real number, all the powers x↦xα, x≥0 and 0<α≤[Formula presented] for x≥0, if (d1,...,dn) ranges over the degree sequences of graphs with n vertices and m edges, then the minimum of ∑ig(di) is uniquely attained by the degree sequence of a quasi-complete graph, i.e., a graph consisting of a complete graph plus possibly an additional vertex connected to some but not all vertices of the complete graph, plus possibly isolated vertices. This result extends a similar result in the same paper.

Let X be a centered random vector in a finite-dimensional real inner product space E. For a subset C of the ambient vector space V of E and x,y is an element of V, write x <= Cy if y-x is an element of C. If C is a closed convex cone in E, then <= C is a preorder on V, whereas if C is a proper cone in E, then <= C is actually a partial order on V. In this paper, we give sharp Cantelli-type inequalities for generalized tail probabilities such as PrX >= Cb for b is an element of V. These inequalities are obtained by "scalarizing" X >= Cb via cone duality and then by minimizing the classical univariate Cantelli's bound over the scalarized inequalities. Three diverse applications to random matrices, tails of linear images of random vectors, and network homophily are also given.

Releasing capsules are widely employed in biomedical applications as smart carriers of therapeutic agents, including drugs and bioactive compounds. Such delivery vehicles typically consist of a loaded core, enclosed by one or multiple concentric coating strata. In this work, we extended existing mechanistic models to account for such multi-strata structures, including possible concurrent erosion of the capsule itself, and we characterized the release kinetics of the active substance into the surrounding medium. We presented a computational study of drug release from a spherical microcapsule, modeled through a non-linear diffusion equation incorporating radial asymmetric diffusion and space- and time-discontinuous coefficients, as suggested by the experimental data specifically collected for this study. The problem was solved numerically using a finite volume scheme on a grid with adaptive spatial and temporal resolution. Analytical expressions for concentration and cumulative release were derived for all strata, enabling the exploration of parameter sensitivity—such as coating permeability and internal diffusivity—on the overall release profile. The resulting release curves provide mechanistic insight into the transport processes and offer design criteria for achieving controlled release. Model predictions were benchmarked against in vitro experimental data obtained under physiologically relevant conditions, showing good agreement and validating the key features of the model. The proposed model thus serves as a practical tool for predicting the behavior of composite coated particles, supporting performance evaluation and the rational design of next-generation drug delivery systems with reduced experimental effort.