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In recent years, there has been growing interest in logics that formalise strategic reasoning about agents capable of modifying the structure of a given model. This line of research has been motivated by applications where a modelled system evolves over time, such as communication networks, security protocols, and multi-agent planning. In this paper, we introduce three logics for reasoning about strategies that modify the topology of weighted graphs. In Strategic Deconstruction Logic, a destructive agent (the demon) removes edges up to a certain cost. In Strategic Construction Logic, a constructive agent (the angel) adds edges within a cost bound. Finally, Strategic Update Logic combines both agents, who may cooperate or compete. We study the expressive power of these logics and the complexity of their model checking problems.
We derive the rational generating function that enumerates the angels and devils in M. C. Escher's {\it Circle Limit IV} according to their combinatorial distance from the six creatures whose feet meet at the center of the disk. This result shows that the base of the exponential rate of growth is $1.582\ldots$ (the largest root of the polynomial $1 - z^2 - 2z^3 - z^4 + z^6$).
External funding is crucial for early-stage ventures, particularly technology startups that require significant R&D investment. Business angels offer a critical source of funding, but their decision-making is often subjective and resource-intensive for both investor and entrepreneur. Much research has investigated this investment process to find the critical factors angels consider. One such tool, the Critical Factor Assessment (CFA), deployed more than 20,000 times by the Canadian Innovation Centre, has been evaluated post-decision and found to be significantly more accurate than investors' own decisions. However, a single CFA analysis requires three trained individuals and several days, limiting its adoption. This study builds on previous work validating the CFA to investigate whether the constraints inhibiting its adoption can be overcome using a trained AI model. In this research, we prompted multiple large language models (LLMs) to assign the eight CFA factors to a dataset of 600 transcribed, unstructured startup pitches seeking business angel funding with known investment outcomes. We then trained and evaluated machine learning classification models using the LLM-generate
We have performed a theoretical study of the correlation functions of $K^- d$ and $K^+ d$ pairs and compared them with those provided by the ALICE Collaboration from Pb-Pb collisions, and also from high-multiplicity p-p collisions in the case of $K^+ d$. In addition to implementing the effect of the Coulomb force, the $K^- d$ and $K^+ d$ wave functions are derived from the corresponding strong scattering amplitudes that are built employing a unitarized chiral model for the elementary $K^- N$ and $K^+ N$ interactions. We present results for the impulse approximation, which accounts for single-scattering processes of the kaon with the nucleons of the deuteron, as well as for the solution of the Faddeev equations in the so-called fixed center approximation, which includes multiple rescattering effects. The $K^- d$ correlation function is shown to be very sensitive to both the size of the source and the relative momentum of the interacting pair, with large deviations from the Coulomb baseline and sizable multi-step scattering contributions, effects that are tied to a ${\bar K}N$ strong interaction that is dominated by the influence of the subthreshold resonance $Λ(1405)$. In contrast,
The capability of the ALICE@LHC and STAR@RHIC experiments to reconstruct $D$ mesons has enabled femtoscopic correlation measurements of open-charm mesons in both small and large systems. In this work, we present a theoretical calculation of the correlation functions of $D$ and $\bar{D}$ mesons with nucleons, based on the Koonin-Pratt formalism. We employ an effective Lagrangian to model the interaction between charmed mesons and baryons and apply the TROY formalism to obtain the off-shell $T$-matrix in coupled channels, incorporating the effect of the Coulomb interaction when the pair involves two charged particles. The resulting full coupled-channel wave function is inserted into the Koonin-Pratt equation with channel weights derived from a thermal model. Additionally, we compute the correlation functions using the Lednický-Lyuboshitz approximation with low-energy scattering parameters extracted from the unitarized amplitudes. We compare these two approaches and provide predictions for different correlated pairs. Our results can be tested against current and future experimental data from the ALICE and STAR collaborations in both proton-proton and heavy-ion collisions.
We investigate the hyperonic equation of state within the non-linear derivative model that incorporates a momentum dependence on the interactions, with a special emphasis on properly establishing the conditions for hyperon appearance in neutron star matter. We demonstrate that hyperons can appear at finite momentum, forming a so-called ``moat" region, even when they are absent at lower momenta. Our study shows that this phenomenon significantly alters the composition and equation of state of hyperonic matter as compared to the cases when it is disregarded, highlighting the importance of accurately treating the momentum dependence of the baryon fields in dense matter.
We prove the existence of complete minimal surfaces in $\mathbb{R}^3$ of arbitrary genus $p\, \ge\, 1$ and least total absolute curvature with precisely two ends -- one catenoidal and one Enneper-type -- thereby solving, affirmatively, a problem posed by Fujimori and Shoda. These surfaces, which are called \emph{Angel surfaces}, generalize some examples numerically constructed earlier by Weber. The construction of these minimal surfaces involves extending the orthodisk method developed by Weber and Wolf \cite{weber2002teichmuller}. A central idea in our construction is the notion of \emph{partial symmetry}, which enables us to introduce controlled symmetry into the surface.
We give a decision procedure and proof of correctness for the equational theory of probabilistic Kleene algebra with angelic nondeterminism introduced in Ong, Ma, and Kozen (2025).
The Los Angeles wildfires of January 2025 caused more than 250 billion dollars in damage and lasted for nearly an entire month before containment. Following our previous work, the Digital Twin Building, we modify and leverage the multi-agent large language model framework as well as the cloud-mapping integration to study the air quality during the Los Angeles wildfires. Recent advances in large language models have allowed for out-of-the-box automated large-scale data analysis. We use a multi-agent large language system comprised of an Instructor agent and Worker agents. Upon receiving the users' instructions, the Instructor agent retrieves the data from the cloud platform and produces instruction prompts to the Worker agents. The Worker agents then analyze the data and provide summaries. The summaries are finally input back into the Instructor agent, which then provides the final data analysis. We test this system's capability for data-based policy recommendation by assessing our Instructor-Worker LLM system's health recommendations based on air quality during the Los Angeles wildfires.
We study the influence of hyperons in binary neutron star (NS) mergers considering a total of 14 temperature dependent equations of state (EoSs) models which include hyperonic degrees of freedom and partly delta resonances. Thermally produced hyperons induce a higher heat capacity and a lower thermal index, i.e. a reduced thermal pressure for a given amount of thermal energy, compared to purely nucleonic models. We run a large set of relativistic hydrodynamics simulations of NS mergers to explore the impact on observables of these events. In symmetric binaries, we describe a characteristic increase of the dominant postmerger gravitational-wave (GW) frequency by a few per cent, which is specifically linked to the occurrence of hyperons and can thus be potentially used as a discriminator between purely nucleonic and hyperonic systems. We corroborate that this effect occurs similarly for asymmetric binaries and becomes more prominent with increasing total binary mass. Hyperonic models tend to stick out in relations between the dominant postmerger GW frequency and the tidal deformability of massive stars providing a signature to identify the presence of hyperons. Distinct secondary pos
We discuss the effects induced by the potential presence of hyperons in hot and ultra-dense matter within the context of neutron star mergers. Specifically, we address their effect on the dominant post-merger frequency of the gravitational waves. By performing a simulation campaign with a large sample of hyperonic and nucleonic equations of state, we explicitly show that the unique thermal behavior of hyperonic equations of state results in a systematic shift of the dominant frequency with respect to the nucleonic reference level. The predicted shift has values of up to 150 Hz, and it could be detected with the newest generations of gravitational wave detectors. Thus this approach opens a new path for signaling the presence of hyperons in neutron star remnant matter.
This study develops a Bayesian hierarchical model to explore the effects of air pollution on respiratory and cardiovascular mortality in Los Angeles County. The model takes into account various pollutants such as PM2.5, PM10, CO, SO2, NO2 and O3, as well as a related meteorological factor: temperature. The objective is to identify the significant factors affecting selected health outcomes without including all variables in each model specification. This flexibility enables the model to capture key drivers of health risk without redundancy. To account for potential measurement error in pollution data due to imperfect monitoring or averaging, certain observed pollutant levels are treated as noise proxies for true exposure. By specifying priors for regression coefficients and measurement error parameters and estimating posterior distributions via Markov Chain Monte Carlo (MCMC) sampling, it leads to more precise and reliable estimates of the health risks associated with air pollution exposure in Los Angeles County by incorporating both the count nature of the health data and the uncertainties in pollution measurements.
We show that if $X$ is a sequentially reflexive Banach space, then its Mackey dual $(X^{*},τ(X^{*}, X))$ is an angelic space. This builds on a result of J. Howard which says that in the Mackey dual $(X^{*}, τ(X^{*}, X))$ of a Banach space $X$, relative sequential compactness is, in general, strictly stronger than relative compactness and that the two notions of compactness are equivalent if $X$ is reflexive or separable. Our main result gives a characterization of the sequentially reflexive spaces as the Banach spaces $X$ for which the the finest locally convex topology on $X^{*}$ with the same precompact sets as the Mackey topology $τ(X^{*}, X)$ is the bound extension of $τ(X^{*}, X)$.
We show reflectivity cross-sections for the San Gabriel, Chino, and San Bernardino basins north of Los Angeles, California determined from autocorrelations of ambient noise and teleseismic earthquake waves. These basins are thought to channel the seismic energy from earthquakes on the San Andreas Fault to Los Angeles and a more accurate model of their depth is important for hazard mitigation. We use the causal side of the autocorrelation function to determine the zero-offset reflection response. To minimize the smoothing effect of the source time function, we remove the common mode from the autocorrelation in order to reveal the zero-offset reflection response. We apply this to 10 temporary nodal lines consisting of a total of 758 geophones with an intraline spacing of 250-300 m. We also show that the autocorrelation function from teleseismic events can provide illumination of subsurface that is consistent with ambient noise. Both autocorrelation results compare favorably to receiver functions.
We have calculated the femtoscopic correlation functions of meson-baryon pairs in the strangeness $S=-1$ sector, employing a unitarized chiral interaction model up to next-to-leading order. We will show preliminary results for the $π^-Λ$ correlation function, which is presently under analysis by the ALICE@LHC collaboration. We will also demonstrate that, within $2σ$, the employed interaction is perfectly capable of reproducing the $K^-p$ correlation function data measured by the same collaboration, without the need of changing the coupled-channel interactions, as has been suggested recently.
We introduce a version of probabilistic Kleene algebra with angelic nondeterminism and a corresponding class of automata. Our approach implements semantics via distributions over multisets in order to overcome theoretical barriers arising from the lack of a distributive law between the powerset and Giry monads. We produce a full Kleene theorem and a coalgebraic theory, as well as both operational and denotational semantics and equational reasoning principles.
Very recently, the Belle~II Collaboration presented a measurement for the decays $B^+\to\bar{D}^{(*)0} K^+\bar{K}^0$ and $B^0\to D^{(*)-}K^+\bar{K}^0$, the bulk of observed $m(K^+ K_S^0)$ distributions showing low-mass structures in all four channels. In this work, we study the contributions of $ρ(770,1450)^+$, $a_2(1320)^+$ and $a_0(980,1450)^+$ resonances to these decay processes. The intermediate states $ρ(770,1450)^+$ are found to dominate the low-mass distribution of kaon pairs roughly contributing to half of the total branching fraction in each of the four decay channels. The contribution of the tensor $a_2(1320)^+$ meson is found to be negligible. Near the threshold of the kaon pair, the state $a_0(980)^+$ turns out to be much less important than expected, not being able to account for the enhancement of events in that energy region observed in the $B^+\to\bar{D}^{(*)0} K^+\bar{K}^0$ decays. Further studies both from the theoretical and experimental sides are needed to elucidate the role of the non-resonant contributions governing the formation of $K^+\bar{K}^0$ pairs near their threshold in these decay processes.
Mesons with heavy flavor content are an exceptional probe of the hot QCD medium produced in heavy-ion collisions. In the past few years, significant progress has been made toward describing the modification of the properties of heavy mesons in the hadronic phase at finite temperature. Ground-state and excited-state thermal spectral properties can be computed within a self-consistent many-body approach that employs appropriate hadron-hadron effective interactions, providing a unique opportunity to confront hadronic Effective Field Theory predictions with recent and forthcoming lattice QCD simulations and experimental data. In this article, we revisit the application of the imaginary-time formalism to extend the calculation of unitarized scattering amplitudes from the vacuum to finite temperature. These methods allow us to obtain the ground-state thermal spectral functions. The thermal properties of the excited states that are dynamically generated within the molecular picture are also directly accessible. We present here the results of this approach for the open-charm and open-bottom sectors. We also analyze how the heavy-flavor transport properties, which are strongly correlated to
Hadron femtoscopy has turned into a powerful tool for accessing space-time information of heavy-ion collisions as well as for studying final-state interactions of hadrons. Recently, heavy-flavor femtoscopy has become feasible using the ALICE detector at the LHC. We compute the correlation function of $D$ mesons and light mesons using an off-shell $T$-matrix approach to access the two-meson wave function, and predict the correlation functions involving charged $D^+, D^{*+},D_s^+$ and $D_s^{*+}$ with $π^\pm$ and $K^\pm$. From the obtained results -- all of them accessible in $p+p$ collision experiments -- we point up the case of $D^+ π^-$, which is sensitive to the lower state of the two-pole $D_0^* (2300)$ system. The presence of such poles imprints a depletion on the correlation function, which could potentially be detected in experiments. While preliminary ALICE data do not show evidence of this effect, we suggest to look into the $D_s^+ K^-$ system to explore the higher pole of the $D_0^* (2300)$, as the depletion in the correlation function is more pronounced. Using heavy-quark spin symmetry we also propose exploring the effect of the two poles of the $D_1(2430)$ and predict sim
We provide the first comprehensive study of hyperons in neutron star mergers and quantify their specific impact. We discuss the thermal behavior of hyperonic equations of state~(EoSs) as a distinguishing feature from purely nucleonic models in the remnants of binary mergers using a large set of numerical simulations. Finite temperature enhances the production of hyperons, which leads to a reduced pressure as highly degenerate nucleons are depopulated. This results in a characteristic increase of the dominant postmerger gravitational-wave frequency by up to $\sim150$~Hz compared to purely nucleonic EoS models. By our comparative approach we can directly link this effect to the occurrence of hyperons. Although this feature is generally weak, it is in principle measurable if the EoS and stellar parameters of cold neutron stars are sufficiently well determined. Considering that the mass-radius relations of purely nucleonic and hyperonic EoSs may be indistinguishable and the overall challenge to infer the presence of hyperons in neutron stars, these findings are important as a new route to answer the outstanding question about hyperonic degrees of freedom in high-density matter.