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Optical pumping of barium monofluoride (BaF) within a cryogenic neon matrix is demonstrated. Interestingly, with an applied magnetic field of 2~G, optical pumping is found to be considerably more efficient for a laser beam with right-circular polarization compared to left-circular polarization. Calculations show that the higher efficiency is due to a constructive versus destructive interference and is dependent on the orientation of the BaF molecule relative to the magnetic field direction. The effect leads to orientation-dependent optical pumping within the matrix. As optical pumping is the first step used in our planned electron electric-dipole moment (eEDM) measurement, we intend to exploit this property to obtain the selection of molecular orientations that is required for an eEDM measurement., Comment: 9 pages, 5 figures

A method for specular reflection of polar molecules is proposed. Electrostatatic potentials and forces are calculated for a low-field-seeking molecule near a series of long cylindrical electrodes of radius $r$ with dc potentials of $+V$ and $-V$ applied to alternate electrodes. A center-to-center separation of $2.9\,r$ leads to remarkably flat equipotential surfaces and thus to a nearly planar mirror for specular reflection of the polar molecules, with the angle of reflection equalling the angle of incidence to an accuracy approaching a microradian. This mirror can be used to redirect cryogenic molecular beams. Separating barium monofluoride (BaF) molecules created in a helium-buffer-gas laser-ablation source from other ablation products is a necessary step to producing a pure sample of matrix-isolated BaF, as is required by the EDM$^3$ collaboration for implementing a precise measurement of the electron electric dipole moment. The design and modelling for the BaF deflector based on this electrode geometry is presented., Comment: 5 pages, 5 figures

A cryogenic neon solid doped with barium monofluoride (BaF) is created on a cryogenic substrate using a stream of Ne gas and a high-intensity beam of BaF molecules produced in a cryogenic helium-buffer-gas laser-ablation source. The apparatus is designed for eventual use in a measurement of the electron electric dipole moment (eEDM). Laser-induced fluorescence is observed from transitions up to the $B\,^2\Sigma_{1/2}$ state. The number of BaF molecules found to be present in the solid and addressable with this laser transition is approximately 10$^{10}$ per mm$^3$, which is of the same order as the total number of BaF molecules that impact the substrate during the hour of growth time for the solid. As a result, an eventual eEDM measurement could have continual access to an accumulation of an hour's worth of molecules (all of which are contained within a 1-mm$^3$ volume and are thermalized into the ground state), compared to beam experiments which study the molecules from a single ablation during the millisecond-timescale of their passage through a much larger-scale measurement apparatus. The number of BaF molecules observed in the doped solid matches the target value for our planned eEDM measurement., Comment: 9 pages, 6 figures

We have developed a computer code for the thermodynamic hierarchical equations of motion derived from a spin subsystem coupled to multiple Drude baths at different temperatures, which are connected to or disconnected from the subsystem as a function of time. The code can simulate the reduced dynamics of the subsystem under isothermal, isentropic, thermostatic, and entropic conditions. The extensive and intensive thermodynamic variables are calculated as physical observables, and Gibbs and Helmholtz energies are evaluated as intensive and extensive work. The energy contribution of the system--bath interaction is evaluated separately from the subsystem using the hierarchical elements of the HEOM. The accuracy of the calculated results for the equilibrium distribution and the two-body correlation functions are assessed by contrasting the results with those obtained from the time-convolution-less Redfield equation. It is shown that the Lindblad master equation is inappropriate for thermodynamic description of a spin--boson system. Non-Markovian effects in thermostatic processes are investigated by sequentially turning on and off the baths at different temperatures with different switching times and system--bath coupling. In addition, the Carnot cycle is simulated under quasi-static conditions. To analyze the work done for the subsystem in the cycle, thermodynamic work diagrams are plotted as functions of intensive and extensive variables. The C++ source codes are provided as supplementary material., Comment: 16 Pages, 10 figures

We developed a computer code for the thermodynamic quantum Fokker-Planck equations (T-QFPE), derived from a thermodynamic system-bath model. This model consists of an anharmonic subsystem coupled to multiple Ohmic baths at different temperatures, which are connected to or disconnected from the subsystem as a function of time. The code numerically integrates the T-QFPE and their classical expression to simulate isothermal, isentropic, thermostatic, and entropic processes in both quantum and classical cases. The accuracy of the results was verified by comparing the analytical solutions of the Brownian oscillator. Additionally, we illustrated a breakdown of the Markovian Lindblad-master equation in the pure quantum regime. As a demonstration, we simulated a thermostatic Stirling engine employed to develop non-equilibrium thermodynamics [S. Koyanagi and Y. Tanimura, J. Chem. Phys 161, 114113 (2024)] under quasi-static conditions. The quasi-static thermodynamic potentials, described as intensive and extensive variables, were depicted as work diagrams. In the classical case, the work done by the external field is independent of the system-bath coupling strength. In contrast, in the quantum case, the work decreases as the coupling strength increases due to quantum entanglement between the subsystem and bath. The codes were developed for multicore processors using Open multiprocessing (OpenMP) and for graphics processing units (GPU) using the Compute United Device Architecture (CUDA). These codes are provided as supplementary materials., Comment: 13 pages, 6 figures

This paper presents a novel approach to causal discovery through a divide-and-conquer framework. By decomposing the problem into smaller subproblems defined on Markov blankets, the proposed DCDILP method first explores in parallel the local causal graphs of these subproblems. However, this local discovery phase encounters systematic challenges due to the presence of hidden confounders (variables within each Markov blanket may be influenced by external variables). Moreover, aggregating these local causal graphs in a consistent global graph defines a large size combinatorial optimization problem. DCDILP addresses these challenges by: i) restricting the local subgraphs to causal links only related with the central variable of the Markov blanket; ii) formulating the reconciliation of local causal graphs as an integer linear programming method. The merits of the approach, in both terms of causal discovery accuracy and scalability in the size of the problem, are showcased by experiments and comparisons with the state of the art.

We have developed a thermodynamic theory in the non-equilibrium regime, which we describe as a thermodynamic system-bath model [S. Koyanagi and Y. Tanimura, J. Chem. Phys. \textbf{160}, 234112 (2024)]. Based on the dimensionless (DL) minimum work principle, non-equilibrium thermodynamic potentials are expressed in terms of non-equilibrium extensive and intensive variables in time derivative form. This is made possible by incorporating the entropy production rate into the definitions of non-equilibrium thermodynamic potentials. These potentials can be evaluated from the DL non-equilibrium-to-equilibrium minimum work principle, which is derived from the principle of DL minimum work and is equivalent to the second law of thermodynamics. We thus obtain the non-equilibrium Massieu-Planck potentials as entropic potentials and the non-equilibrium Helmholtz-Gibbs potentials as free energies. Unlike fluctuation theorem and stochastic thermodynamics theory, this theory does not require the assumption of a factorized initial condition and is valid in the full quantum regime where the system and bath are quantum mechanically entangled. Our results are numerically verified by simulating a thermostatic Stirling engine consisting of two isothermal processes and two thermostatic processes using the quantum hierarchical Fokker--Planck equations and the classical Kramers equation derived from the thermodynamic system-bath model. We then show that, from weak to strong system-bath interactions, the thermodynamic process can be analyzed using a non-equilibrium work diagram analogous to the equilibrium one for given time-dependent intensive variables. The results can be used to develop efficient heat machines in non-equilibrium regimes., Comment: 16 pages, 10 Figures, 9 tables

We formulate a thermodynamic theory applicable to both classical and quantum systems. These systems are depicted as thermodynamic system-bath models capable of handling isothermal, isentropic, thermostatic, and entropic processes. Our approach is based on the use of a dimensionless thermodynamic potential expressed as a function of the intensive and extensive thermodynamic variables. Using the principles of dimensionless minimum work and dimensionless maximum entropy derived from quasi-static changes of external perturbations and temperature, we obtain the Massieu-Planck potentials as entropic potentials and the Helmholtz-Gibbs potentials as free energy. These potentials can be interconverted through time-dependent Legendre transformations. Our results are verified numerically for an anharmonic Brownian system described in phase space using the low-temperature quantum Fokker-Planck equations in the quantum case and the Kramers equation in the classical case, both developed for the thermodynamic system-bath model. Thus, we clarify the conditions for thermodynamics to be valid even for small systems described by Hamiltonians and establish a basis for extending thermodynamics to non-equilibrium conditions., Comment: 19 pages, 4 figures, 7 tables

XAI (eXplanable AI) techniques that have the property of explaining the reasons for their conclusions, i.e. explainability or interpretability, are attracting attention. XAI is expected to be used in the development of forensic science and the justice system. In today's forensic and criminal investigation environment, experts face many challenges due to large amounts of data, small pieces of evidence in a chaotic and complex environment, traditional laboratory structures and sometimes inadequate knowledge. All these can lead to failed investigations and miscarriages of justice. In this paper, we describe the application of one logical approach to crime scene investigation. The subject of the application is ``The Adventure of the Speckled Band'' from the Sherlock Holmes short stories. The applied data is the knowledge graph created for the Knowledge Graph Reasoning Challenge. We tried to find the murderer by inferring each person with the motive, opportunity, and method. We created an ontology of motives and methods of murder from dictionaries and dictionaries, added it to the knowledge graph of ``The Adventure of the Speckled Band'', and applied scripts to determine motives, opportunities, and methods., Comment: 11 pages, 11 figures

GitHub Copilot is an AI-enabled tool that automates program synthesis. It has gained significant attention since its launch in 2021. Recent studies have extensively examined Copilot's capabilities in various programming tasks, as well as its security issues. However, little is known about the effect of different natural languages on code suggestion. Natural language is considered a social bias in the field of NLP, and this bias could impact the diversity of software engineering. To address this gap, we conducted an empirical study to investigate the effect of three popular natural languages (English, Japanese, and Chinese) on Copilot. We used 756 questions of varying difficulty levels from AtCoder contests for evaluation purposes. The results highlight that the capability varies across natural languages, with Chinese achieving the worst performance. Furthermore, regardless of the type of natural language, the performance decreases significantly as the difficulty of questions increases. Our work represents the initial step in comprehending the significance of natural languages in Copilot's capability and introduces promising opportunities for future endeavors.