Formulation Of Theory Research Articles

Vibrational Features of Oxyamines: A Comparative Study of N,N-Diethylhydroxylamine and N,N-Diethylacetyloxyamine.

The ability of oxyamines to undergo homolytic cleavage of the O-C bond, leading to the formation of stable radicals, is widely used in polymerization processes and to prevent oxidative stress in materials. We present a mid and near-infrared spectroscopy study on two model compounds, N,N-diethylhydroxyloxyamine (C4H11NO) and its acetyl derivative N,N-diethylacetyloxyamine (C6H13NO2) in the liquid phase. The analysis of the spectra is based on a complete exploration of the conformational space, coupled to harmonic and anharmonic calculations performed using the generalized second-order vibrational perturbation theory (GVPT2) formalism at the B3LYP-D3(BJ)/Def2-TZVP level of calculation and potential energy distribution analysis. In the most stable species out of 25, the three amine chains present an all-anti arrangement, with the carbonyl oxygen atom pointing towards the nitrogen lone pair. The simulated spectra are in overall good agreement with the experimental ones, and suitable for the assignment of the main observed bands. Furthermore, similarities and divergences between the two molecules are discussed.

An energy-modified quantum defect method for the analysis of Rydberg spectra: Application to 2-butyne.

The high resolution Rydberg absorption spectrum of 2-butyne C4H6 recorded previously at the SOLEIL synchrotron facility has been interpreted using multichannel quantum defect theory (MQDT). The calculations are based on the continuum scattering calculations of Xu et al., J. Chem. Phys. 136, 154303 (2012) and of Jacovella et al., J. Phys. Chem. A 119, 12339 (2015) pertaining to the dipole-allowed excited state symmetries in absorption from the ground state. In contrast to the traditional approach of calculating low-lying electronic states first and then attempting to extend the calculations to ever higher energy, here the analysis proceeds through the extension of these detailed calculations of the electronic continuum scattering down into the discrete region of the spectrum. The continuum reaction matrices and dipole transition moments are adapted to the discrete Rydberg region via the use of an energy-modified formulation of MQDT theory and associated energy dependences of the quantum defects. The analysis reproduces more than 40 Rydberg states from n ≈ 10 down to the 3d and 4s levels with an rms error of better than 20 cm-1. These belong to five Rydberg series with three different molecular symmetries. While the approach predicts many additional series, most of these are calculated and observed to carry only little oscillator strength. The analysis shows that the Rydberg spectrum is dominated by the excitation of an e″ symmetry electron of fδ and gπ type, in line with what previous studies of the above-threshold shape resonance of 2-butyne have shown. The present study is intended to serve as an example showing how first principles continuum calculations may be useful for the interpretation of highly bound discrete states in a range that poses problems for the standard abinitio techniques. The quantitative treatment of the dipole absorption cross sections is deferred to a future paper.

Light-induced orbital magnetism in metals via inverse Faraday effect

We present a microscopic calculation of the inverse Faraday effect in metals. We derive a static local magnetic moment induced on the application of high-frequency light, using the Eilenberger formulation of quasiclassical theory. We include the effect of disorder and formulate a theory applicable across the entire temperature range, in the absence of external applied fields. For light-induced electric fields of amplitude ∼100kV/cm, the induced fields are large ∼0.1T for metallic Nb. The predictions of our theory agree with recent experimental and theoretical results [O. H.-C. Cheng , and J. Hurst , ]. An extension of this approach to superconductors would open a new route of inducing orbital magnetic field and potentially vortices in superconductors. Published by the American Physical Society 2024

Black holes and wormholes beyond classical general relativity

In the paper only Static Spherically Symmetric space–times in four dimension are considered within modified gravity models. The non-singular static metrics, including black holes not admitting a de Sitter core in the center and traversable wormholes, are reconsidered within a class of higher-order F(R), satisfying the constraints F(0)=dFdR(0)=0. Furthermore, making use of the so called effective field theory formulation of gravity, the quantum corrections to Einstein–Hilbert action due to higher-derivative terms related to curvature invariants are investigated. In particular, in the case of Einstein–Hilbert action plus cubic curvature Goroff–Sagnotti contribution, the second order correction in the Goroff–Sagnotti coupling constant is computed. In general, it is shown that the effective metrics, namely Schwarzschild expression plus small quantum corrections are related to black holes, and not to traversable wormholes. In this framework, within the approximation considered, the resolution of singularity for r=0 is not accomplished. The related properties of these solutions are investigated.

I Know It When I Hear It

In the following article I consider a catalog of audio description porn videos available on the online adult entertainment platform Pornhub. Attending to the visual and aural elements of the original source video and their simultaneous narration in the audio descriptive tracks, I argue that this transcription offers us, the viewer/auditor, an ekphrastic encounter with the pornographic moving image mediated by the acousmatic gendered voice of the audio describer. While academic scholarship on pornography informs my discussion of the source videos, theories of ekphrasis ranging from its usage in Ancient Greek rhetoric, to its formulation in twentieth-century anglophone literary theory, and finally to its application in digital visual culture, will underpin my analysis of the audio description. Through ekphrasis I ultimately distinguish the audio description of pornography as a creative genre in its own right, as well as offer an extensive and interdisciplinary approach that extends beyond the recursive or self-reflexive lens of porn studies scholarship, and newly positions hardcore film pornography within a larger body of academic inquiry in conversation with epic poetry and art history.

Alternative payment models in Dutch hospital care: what works, how, why and under what circumstances? Protocol for a realist evaluation study

IntroductionThe predominant provider payment models in healthcare, particularly fee-for-service, hinder the delivery of high-value care and can encourage healthcare providers to prioritise the volume of care over the value of...

Green/WeakCoupling: Implementation of fully self-consistent finite-temperature many-body perturbation theory for molecules and solids

The accurate ab-initio simulation of molecules and periodic solids with diagrammatic perturbation theory is an important task in quantum chemistry, condensed matter physics, and materials science. In this article, we present the WeakCoupling module of the open-source software package Green, which implements fully self-consistent diagrammatic weak coupling simulations, capable of dealing with real materials in the finite-temperature formalism. The code is licensed under the permissive MIT license. We provide self-consistent GW (scGW) and self-consistent second-order Green's function perturbation theory (GF2) solvers, analysis tools, and post-processing methods. This paper summarises the theoretical methods implemented and provides background, tutorials and practical instructions for running simulations. Program summaryProgram Title:Green/WeakCouplingCPC Library link to program files:https://doi.org/10.17632/2ysyhzww6t.1Developer's repository link:https://github.com/Green-Phys/green-mbptProgramming language:C++17, CUDA, PythonLicensing provisions: MIT LicenseExternal routines/libraries:MPI >= 3.0, BLAS, Eigen >= 3.4.0, cmake >= 3.18, cuBLAS.Nature of problem: The simulation of periodic solids and molecules using diagrammatic perturbation theorySolution method: We present an open-source implementation of the fully self-consistent finite-temperature many-body perturbation theory formalism at the GW and second-order perturbation theory level.

Metaphors Describing the Gendered Organization in the Career Advancement of Women: An Integrative Review

Worldwide, gender equality remains a barrier for women seeking career advancement in corporations. Despite the globalization of corporate social responsibility programs, women have not achieved positional parity with men within the managerial hierarchy. The purpose of this integrative review was to investigate the breadth of the gendered organization literature, summarize the evidence, and inform future research about the career advancement of women in privately owned and publicly traded corporations. Twelve databases were searched between January 1990 and December 2023 for published evidence. Of the 1914 documents screened, 55 articles were included in this review. The gendered organization literature is slowly evolving as a critical area for management research even though fully developed substantive and formal theories are lacking. However, gendered organizations can be conceptualized for theoretical development as a constellation of metaphors embedded in the corporate culture. These metaphors include firewalls, glass ceilings, glass cliffs, glass escalators, labyrinths, queen bees and beehives, and sticky floors. Notably, few intervention studies were reported in the literature. Corporate social responsibility programs had a surprisingly limited impact on eliminating deep-seated structural attributes contributing to gendered organizations. Therefore, management scholars need to engage in theoretical development and research to advance a comprehensive theory of the gendered organization, and studies should investigate why the identified metaphors continue to adversely impact the career advancement of women despite the presence of corporate social responsibility programs. Finally, existing evidence needs to be translated into intervention recommendations for policymakers and corporate leaders.

Explanation, formal models, and rational choice

Formal theorists use a unified collection of models to generate intentional and causal explanations of political behavior. I explicate this claim and argue that disagreements about the role of unification and intentionality are at the root of persistent friction between theorists and empiricists. A debate around pathologies of rational choice theory is used to illustrate the argument.

Algorithmic formalization: Impacts on administrative processes

AbstractThis paper investigates the influence of algorithms on the administrative processes within public organizations, utilizing the foundational theory of formalization from Walsh and Dewar (1987) as a framework. Introduces the concept of “algorithmic formalization”, a new form of formalization induced by the adoption of algorithms, which fundamentally alters administrative workflows. Focusing on COMPAS algorithm used in the US judiciary for risk assessment, the paper illustrates how the algorithm serves multiple roles – as code, channel, and standard – systematizing administrative processes related to risk assessment and judicial decisions. By delving into COMPAS case study, the research sheds light on the novel concept of algorithmic formalization, emphasizing its significant repercussions for analyzing and applying algorithmic administrative processes.

Multichannel Quantum Defect Theory with a Frame Transformation for Ultracold Atom-Molecule Collisions in Magnetic Fields.

We extend the powerful formalism of multichannel quantum defect theory combined with a frame transformation to ultracold atom-molecule collisions in magnetic fields. By solving the coupled-channel equations with hyperfine and Zeeman interactions omitted at short range, the extended theory enables a drastically simplified description of the intricate quantum dynamics of ultracold molecular collisions in terms of a small number of short-range parameters. We apply the formalism to ultracold Mg+NH collisions in a magnetic field, achieving a 10^{4}-fold reduction in computational effort.

Exploring the molecular solvatochromism, stability, reactivity, and non-linear optical response of resveratrol.

This work analyzes the isomerization effects and solvent contributions to the stability, electronic excitations, reactivity, and non-linear optical properties (NLO) of resveratrol molecules within the formalism of the Density Functional Theory. The findings suggest that resveratrol solvatochromism is significantly influenced by solvent polarization. The electronic and free energies (E and G) indicate that trans is the most stable conformer. The system is classified as a strong nucleophile. However, the analysis of the Fukui functions and the Mulliken charges indicate that cis-trans isomerization jointly affects the reactive indices of the carbon and hydrogen atoms. The results also suggest that solvent is relevant to solvatochromism and the NLO response. Both cis and trans conformers present strong excitations that undergo a visible hypsochromic change when the polarity of the solvent increases. Once the absorption spectra are connected to the first hyperpolarization ( ) by the Oudar and Chemla relation, the hypsochromism of resveratrol is the reason for the drop in the generation of the second harmonic when the ambient polarity decreases. The CAM-B3LYP DFT results suggest that resveratrol is interesting for NLO applications. Depending on the choice of solvent, values 50 times those observed for urea ( esu), which is a standard NLO material. The optimized geometries of cis and trans isomers of resveratrol in vacuum were obtained using Density Functional Theory (DFT) with the hybrid exchange-correlation function (CAM-B3LYP) and Pople basis set functions, specifically 6-311++G(d,p). The solvent effect on the geometries of both isomers was included using the polarizable continuum model (PCM) with the same level of QM calculation. Vibrational analysis was conducted to confirm that all optimized geometries correspond to the minimum energy. Various electronic properties, including dipole moments, molecular orbitals, transition energy, dipole polarizabilities, and global reactivity parameters, were calculated using both continuum and discrete solvation models based on the sequential QM/MM methodology. All QM calculations were performed with the Gaussian 09 program and the MC simulations with the DICE program. All NLO analysis was carried out using the Multiwfn code.

On the (in)consistency of perturbation theory at finite temperature

A well-known difficulty of perturbative approaches to quantum field theory at finite temperature is the necessity to address theoretical constraints that are not present in the vacuum theory. In this work, we use lattice simulations of scalar correlation functions in massive ϕ4 theory to analyse the extent to which these constraints affect the perturbative predictions. We find that the standard perturbative predictions deteriorate even in the absence of infrared divergences at relatively low temperatures, and that this is directly connected to the analytic structure of the propagators used in the expansion. This suggests that the incorporation of non-perturbative thermal effects in the propagators is essential for a consistent perturbative formulation of scalar quantum field theories at finite temperature. By utilising the spectral constraints imposed on finite-temperature correlation functions, we explore how these effects manifest themselves in the lattice data, and discuss why the presence of distinct thermoparticle excitations provides a potential resolution to these issues.

Pavlovian safety learning: An integrative theoretical review.

Safety learning involves associating stimuli with the absence of threats, enabling the inhibition of fear and anxiety. Despite growing interest in psychology, psychiatry, and neuroscience, safety learning lacks a formal consensus definition, leading to inconsistent methodologies and varied results. Conceptualized as a form of inhibitory learning (conditioned inhibition), safety learning can be understood through formal learning theories, such as the Rescorla-Wagner and Pearce-Hall models. This review aims to establish a principled conceptualization of 'Pavlovian safety learning', identifying cognitive mechanisms that generate safety and the boundary conditions that constrain it. Based on these observations, we define Pavlovian safety learning as an active associative process, where surprising threat-omission (safety prediction error) acts as a salient reinforcing event. Instead of producing merely neutral or nonaversive states, safety learning endows stimuli with active positive associations to 'safety'. The resulting stimulus-safety memories counteract the influence of fear memories, promoting fear regulation, positive affect, and relief. We critically analyze traditional criteria of conditioned inhibition for their relevance to safety and propose areas for future innovation. A principled concept of Pavlovian safety learning may reduce methodological inconsistencies, stimulate translational research, and facilitate a comprehensive understanding of an indispensable psychological construct.

Engels' Theoretical Contribution to Historical Materialism and its Contemporary Value Implication

As Marx's close comrade-in-arms and revolutionary partner, Engels undertook the major mission of perfecting Marxist philosophy in defense of Marx after Marx's death, but Engels's interpretation of Marxism caused scholars to explore the academic relationship between Marx and Engels, and his book Ludwig Feuerbach and the End of Classical German Philosophy (hereinafter referred to as Engels’Ludwig Feuerbach of 1888) became the focal point of the research on the academic relationship between the two. The work presents Engels' systematic interpretation of the materialist conception of history, his innovative formulation of Engels' theory of historical synergy and the fundamental question of phi-losophy, and is a strong proof of the consistency between the ideas of Marx and Engels. Engels' theoretical contribution to the materialist conception of history in the work still has valuable theoretical value in contemporary times, and inspires us to hold on to Marxism without wavering, and to innovate without stopping, in order to better guide our practice.

Waves and strings in an interacting conformal chiral 2-form theory in six dimensions

In six dimensions there exists a unique one-parameter family of nonlinear conformal electrodynamics for a chiral 2-form gauge field that includes (in a free-field limit) the linear chiral 2-form theory and is related, by dimensional reduction, to the four-dimensional ModMax electrodynamics. In this work, we present the first exact solutions of this theory in presence of gravity. In particular, we will consider plane wave, Robinson-Trautman, and self-dual dyonic string configurations, generalizing well-known solutions of this type in six-dimensional supergravities with linear chiral 2-form multiplets. Published by the American Physical Society 2024

Formal verification of timely knowledge propagation in airborne networks

Ensuring timely coordination between autonomous aircraft is a challenging problem in decentralized air traffic management (ATM) applications for urban air mobility (UAM) scenarios. This paper presents an approach for formally guaranteeing timely progress in a Two-Phase Acknowledge distributed knowledge propagation protocol by probabilistically modeling the delays using the theory of the Multicopy Two-Hop Relay protocol and the M/M/1 queue system. The guarantee states a probabilistic upper bound to the time for progress as a function of the probabilities of the total transmission and processing delays following two specific distributions. The proof uses a general library of formal theories, that can be used for the rigorous mechanical verification of autonomous aircraft coordination protocols using the Athena proof checker and assistant.

Post-Minkowskian theory meets the spinning effective-one-body approach for two-body scattering

Effective-one-body (EOB) waveforms employed by the LIGO-Virgo-KAGRA Collaboration have primarily been developed by resumming the post-Newtonian expansion of the relativistic two-body problem. Given the recent significant advancements in post-Minkowskian (PM) theory and gravitational self-force formalism, there is considerable interest in creating waveform models that integrate information from various perturbative methods in innovative ways. This becomes particularly crucial when tackling the accuracy challenge posed by upcoming ground-based detectors (such as the Einstein Telescope and Cosmic Explorer) and space-based detectors (such as LISA, TianQin, or Taiji) expected to operate in the next decade. In this context, we present the derivation of the first spinning EOB (SEOB) Hamiltonian that incorporates PM results up to three-loop order: the SEOB-PM model. The model accounts for the complete hyperbolic motion, encompassing nonlocal-in-time tails. To evaluate its accuracy, we compare its predictions for the conservative scattering angle, augmented with dissipative contributions, against numerical-relativity data of nonspinning and spinning equal-mass black holes. We observe very good agreement, comparable, and in some cases slightly better to the recently proposed wEOB-potential model, of which the SEOB-PM model is a resummation around the probe limit. Indeed, in the probe limit, the SEOB-PM Hamiltonian and scattering angles reduce to the one of a test mass in Kerr spacetime. Once complemented with nonlocal-in-time contributions for bound orbits, the SEOB-PM Hamiltonian can be utilized to generate waveform models for spinning black holes on quasicircular orbits. Published by the American Physical Society 2024

On the Operational Theory of the CPS-Calculus: Towards a Theoretical Foundation for IRs

The continuation-passing style translation often employed by compilers gives rise to a class of intermediate representation languages where functions are not allowed to return anymore. Though the primary use of these intermediate representation languages is to expose details about a program's control flow, they may be equipped with an equational theory in order to be seen as specialized calculi, which in turn may be related to the original languages by means of a factorization theorem. In this paper, we explore Thielecke's CPS-calculus, a small theory of continuations inspired by compiler implementations, and study its metatheory. We extend it with a sound reduction semantics that faithfully represents optimization rules used in actual compilers, and prove that it acts as a suitable theoretical foundation for the intermediate representation of Appel's and Kennedy's compilers by following the guidelines set out by Plotkin. Finally, we prove that the CPS-calculus is strongly normalizing in the simply typed setting by using a novel proof method for reasoning about reducibility at a distance, from which logical consistency follows. Taken together, these results close a gap in the existing literature, providing a formal theory for reasoning about intermediate representations.

A Coherent Analysis of The Lottery by Shirley Jackson Using Segmented Discourse Representation Theory

Shirley Jackson's The Lottery is a powerful narrative widely analyzed for its social, cultural, and literary dimensions. However, the linguistic intricacies of Jackson's work remain underexplored. This study addresses this gap by applying Segmented Discourse Representation Theory (SDRT) to analyze the discourse structure of The Lottery. SDRT, a formal theory of discourse that emphasizes coherence relations, provides a systematic framework for examining how different narrative segments interact to create a cohesive and impactful story. By employing SDRT, this research uncovers the intricate ways in which Jackson's linguistic choices contribute to the story's thematic depth and emotional resonance. This analysis not only enhances our understanding of Jackson's narrative techniques but also demonstrates the applicability of SDRT in literary discourse analysis, offering new insights into the dynamic development of discourse within literary texts.