Classical Context Research Articles

Classical consequences of constructive systems.

This is a survey of formal axiomatic systems for the three main varieties of constructive analysis, in a common language and with intuitionistic logic, which are as nearly as possible compatible with classical analysis and with one another. Classically sound consequences of principles of intuitionistic mathematics are emphasized. Compatibility with classical analysis is of two kinds. On the one hand, Bishop's constructive mathematics and a very substantial part of intuitionistic analysis are classically correct, sharing with constructive recursive mathematics a neutral subsystem adequate for recursive function theory and elementary real analysis. On the otherhand, each constructive system considered here is separately consistent with the negative interpretation of each of its classically sound subsystems, establishing internal compatibility with the classical context it is intended to refine. A possibly new criterion for the transposability of unique existential quantifiers and a recent theorem of Vafeiadou on the internal compatibility of classical and intuitionistic analysis are included. This article is part of the theme issue 'Modern perspectives in Proof Theory'.

Practical overview of image classification with tensor-network quantum circuits

Circuit design for quantum machine learning remains a formidable challenge. Inspired by the applications of tensor networks across different fields and their novel presence in the classical machine learning context, one proposed method to design variational circuits is to base the circuit architecture on tensor networks. Here, we comprehensively describe tensor-network quantum circuits and how to implement them in simulations. This includes leveraging circuit cutting, a technique used to evaluate circuits with more qubits than those available on current quantum devices. We then illustrate the computational requirements and possible applications by simulating various tensor-network quantum circuits with PennyLane, an open-source python library for differential programming of quantum computers. Finally, we demonstrate how to apply these circuits to increasingly complex image processing tasks, completing this overview of a flexible method to design circuits that can be applied to industrially-relevant machine learning tasks.

Stochastic geometric mechanics in nonequilibrium thermodynamics: Schrödinger meets Onsager *

We are describing relations between Schrödinger’s variational problem and Onsager’s approach to nonequilibrium statistical mechanics. Although the second work on reciprocal relations and detailed balance has been published in the same year (1931) as the first one, the impact of Schrödinger’s idea has not yet been considered in the classical context of Onsager.

Geochemical evolution of magmatic rocks in the Vioolsdrif Domain, Namibia

AbstractGeological, lithological, petrographical, geochemical, and geochronological data in the Palaeoproterozoic Richtersveld Subprovince/Magmatic Arc (RMA) of Precambrian basement rocks of the Vioolsdrif Domain in southern Namibia, strongly support linkages in the history of formation between the volcanic rock types of the Orange River Group (ORG) and the plutonic rocks of the Vioolsdrif Suite (VS). Previous age dating indicates volcanics of the ORG are more-or-less synchronous with granitic phases of the VS. Geochemical, mineralogical, and comprehensive field and petrological characteristics of the volcanic and granitic rocks suggest genetically linked, parallel igneous-effusive rock suites through processes of fractional crystallisation. Intermittent tapping of evolving residual magmas produced an extrusive carapace of volcanic rocks covering the granitic rocks in a classic magmatic differentiation context of parallel geochemical and lithological evolution. As the magma chamber fractionated plutonic phases of the VS at depth, it extruded residual liquids as volcanic flows and ejecta at surface to form the ORG. A first principal model, based on Ba, Rb and Sr trace element and SiO2, MgO, Al2O3, TiO2 major element behaviour, is supported by multivariate modelling of 28 major and trace elements in 129 rock analyses using Principal Component Analysis (PCA). PCA indicates the first four components account for more than 80% of the total compositional variance in all rock types lending comprehensive support for a linked geochemical differentiation model for both the igneous and the volcanic suites. Strong evidence for the magmatic co-evolution of the plutonic and effusive series includes the Cu-mineralisation event, which manifests itself as a resolvable, orthogonal fifth principal component, geochemically overprinting the intermediate ‘porphyry monzogranite’ differentiation stages, but not related to the terminal leuco-granites. The full spectrum of geochemical relationships is consistent with current models of a direct genetic relationship between evolving high Sr/Y magmas and hydrothermal porphyry Cu deposits, in overall agreement with the full context of field, rock, mineralogical, geochemical, and economic geology interpretations presented here.

Surgically retrieved spermatozoa for ICSI cycles in non-azoospermic males with high sperm DNA fragmentation in semen.

Intracytoplasmic sperm injection (ICSI)using surgically retrieved spermatozoa outside the classic context of azoospermia has been increasingly used to overcome infertility. The primary indications include high levelsofsperm DNA damage in ejaculated spermatozoa and severe oligozoospermia or cryptozoospermia, particularly in couples with ICSI failurefor no apparent reason. Current evidence suggests that surgically retrieved spermatozoa for ICSI in the above context improves outcomes, mainly concerning pregnancy and miscarriage rates. The reasons are not fully understood but may be related to the lower levels of DNA damage in spermatozoa retrieved from the testis compared with ejaculated counterparts. These findings are consistent with the notion that excessive sperm DNA damage can be a limiting factor responsible for the failure to conceive. Using testicular in preference of low-quality ejaculated spermatozoa bypasses post-testicular sperm DNA damage caused primarily by oxidative stress, thusincreasing the likelihood of oocyte fertilization by genomically intact spermatozoa. Despite the overall favorable results, data remain limited, andmainly concern males with confirmed sperm DNA damage in the ejaculate. Additionally, information regarding the health of ICSI offspring resulting from theuseofsurgicallyretrievedspermatoaofnon-azoospermicmales is still lacking. Efforts should be made to improve the male partner's reproductive health for safer ICSI utilization. A comprehensive andrological evaluation aiming to identify and treat the underlying male infertility factor contributing to sperm DNA damage is essential for achieving this goal.

What matters? Unlocking householders’ flexibility towards cooling automation in India

In emerging economies like India, where air conditioners are projected to triple by 2050 — mostly from household use — demand response programs such as cooling automation have gained currency as a suitable approach to address peak electricity from cooling demand. Environmentally commoning/intentional communities are classic contexts in which flexible cooling consumption might be easily realised. Utilising materialist theory and a six-month cooling automation trial, surveys and workshops with twenty households in an intentional community in South India, this study explores factors that shape householders’ pliability or rejection of cooling automation. Results reveal that while commoning identity plays a significant role in householders' flexibility towards automation, extreme heat creates a clash between householders' environmental beliefs and comfort needs, altering their response to automation. We conclude by discussing the theoretical implications arising from these findings and suggest how utilities could respond to these dynamics to foster a transition to a low-carbon energy system.

Improved FRQI on superconducting processors and its restrictions in the NISQ era

In image processing, the amount of data to be processed grows rapidly, in particular when dealing with images of more than two dimensions or time series of images. Thus, efficient processing is a challenge, as data sizes may push even supercomputers to their limits. Quantum image processing promises to encode images with logarithmically less qubits than classical pixels in the image. In theory, this is a huge progress, but so far not many experiments have been conducted in practice, in particular on real backends. Often, the precise conversion of classical data to quantum states, the exact implementation, and the interpretation of the measurements in the classical context are challenging. We investigate these practical questions in this paper. In particular, we study the feasibility of the flexible representation of quantum images (FRQI). Furthermore, we check experimentally the limit in the current noisy intermediate-scale quantum era, i.e., up to which image size an image can be encoded, both on simulators and on real backends. Finally, we propose a method for simplifying the circuits needed for the FRQI. With our alteration, the number of gates can be reduced, especially the one of the error-prone controlled-NOT gates. As a consequence, the size of manageable images increases.

Algebraic (super-)integrability from commutants of subalgebras in universal enveloping algebras

Starting from a purely algebraic procedure based on the commutant of a subalgebra in the universal enveloping algebra of a given Lie algebra, the notion of algebraic Hamiltonians and the constants of the motion generating a polynomial symmetry algebra is proposed. The case of the special linear Lie algebra is discussed in detail, where an explicit basis for the commutant with respect to the Cartan subalgebra is obtained, and the order of the polynomial algebra is computed. It is further shown that, with an appropriate realization of , this provides an explicit connection with the generic superintegrable model on the -dimensional sphere and the related Racah algebra R(n). In particular, we show explicitly how the models on the two-sphere and three-sphere and the associated symmetry algebras can be obtained from the quadratic and cubic polynomial algebras generated by the commutants defined in the enveloping algebra of and , respectively. The construction is performed in the classical (or Poisson-Lie) context, where the Berezin bracket replaces the commutator.

Invasive Pulmonary Aspergillosis.

Invasive pulmonary aspergillosis is growing in incidence, as patients at risk are growing in diversity. Outside the classical context of neutropenia, new risk factors are emerging or newly identified, such as new anticancer drugs, viral pneumonias and hepatic dysfunctions. Clinical signs remain unspecific in these populations and the diagnostic work-up has considerably expanded. Computed tomography is key to assess the pulmonary lesions of aspergillosis, whose various features must be acknowledged. Positron-emission tomography can bring additional information for diagnosis and follow-up. The mycological argument for diagnosis is rarely fully conclusive, as biopsy from a sterile site is challenging in most clinical contexts. In patients with a risk and suggestive radiological findings, probable invasive aspergillosis is diagnosed through blood and bronchoalveolar lavage fluid samples by detecting galactomannan or DNA, or by direct microscopy and culture for the latter. Diagnosis is considered possible with mold infection in lack of mycological criterion. Nevertheless, the therapeutic decision should not be hindered by these research-oriented categories, that have been completed by better adapted ones in specific settings. Survival has been improved over the past decades with the development of relevant antifungals, including lipid formulations of amphotericin B and new azoles. New antifungals, including first-in-class molecules, are awaited.

Elastic bound states in the continuum by acoustoelastic interaction

One of the most widely-held beliefs was that no such thing as a bound state existed in a continuum. Notably, it only lately emerged to disclose such a state in several domains of wave physics. Here we report the presence of elastic quasi-bound states in the continuum (QBICs) by balancing local Fano and Fabry–Pérot resonant states, with vanishing linewidths nearby which indicate BICs. The rational design is made by directly integrating an acoustic cavity into an elastic bar, which enables the two to interact. The proposed continuum elastic bar is in analogy to the Fano–Anderson discrete model, which further satisfies a criteria for both Fano and Fabry–Pérot resonances to obtain optimal QBIC modes. Experiments are also carried out for proof-of-concept purposes to uncover these states with a good agreement. This platform would be versatile in illustrating generic Fano lineshapes and high Q-factors, bringing up a new avenue for using the acoustoelastic nature. We hope that our findings would also contribute to the understanding of quantum-driven phenomena in classical contexts with sharing the comparable underlying wave physics.

‘Extended’ vocal techniques in the institution: The Extended Vocal Techniques Ensemble at the Center for Musical Experiment at UCSD

In the decades following the Second World War, novel sound technologies and the proliferation of ethnomusicological field recordings ignited curiosity and experimentation among many musicians; these cultural phenomena also sparked a re-examination of conventional Euro-American musical sound sources. Classically trained instrumentalists and singers – particularly those associated with the ‘experimental tradition’ – cultivated intentionally idiosyncratic musical practices and widened their range of sonic possibility; this cultural zeitgeist included a heightened interest in so-called extended vocal techniques. In this article, I examine the research and creative output of the Extended Vocal Techniques Ensemble (EVTE) of the University of California at San Diego (UCSD). Drawing from published literature, interviews and archival sources to write this account of the EVTE’s multifaceted work, I contextualize the group’s activities within UCSD’s interdisciplinary emphasis as well as in the broader social–historical discourses of ‘extended vocal techniques’. Furthermore, I address the implications of their story within the broader politics of vocal aesthetics and pedagogy in Euro-American classical music contexts. By unearthing the EVTE’s interdisciplinary vision for vocal study, I hope to not only spark interest in this ensemble’s contributions, but also to revive (and build upon) their vision of a radically reimagined vocal artistry and study in academic music and beyond.

Varying-G gravity: physical properties, asymptotic regimes, and Green’s functions, an event horizon, the vacuum energy density, and the external pressure that modifies Jeans stability

ABSTRACT We study varying-G gravity and we add the necessary proofs (general force law, asymptotic forms, and Green’s functions, vacuum and external pressures, linearization of perturbations leading to a new Jeans stability criterion, and a physical origin) to elevate this novel idea to the status of a classical theory. The theory we lay out is not merely a correction to Newtonian gravity, it is a brand-new theory of gravity that encompasses the Newtonian framework and weak-field Weyl gravity in the limit of high accelerations, as well as Modified Newtonian Dynamics (MOND) in the opposite limit. In varying-G gravity, the source of the potential of a spherical mass distribution M(x) is σ(dG/dx) + (G/x2)(dM/dx), where x is the dimensionless radial coordinate and σ(x) = M(x)/x2 is the surface density away from the center x = 0. We calculate the potential $\Phi (x)=\int {G(x)\, \sigma (x)\, dx}$ from Poisson’s equation and the radial acceleration $a(x) = G(x)\, \sigma (x)$. Furthermore, a non-linear scaling transformation of the radial coordinate $x\in (0, \infty)\longmapsto \xi \in (0, 1)$ with scale factor ξ/x ∝ 1/G produces a finite space, in which the spherical surface ξ = 1 is an event horizon. In this classical context, it is the coupling of σ(x) to the gradient dG/dx in the above source that modifies the dynamics at all astrophysical scales, including empty space (where dG/dx ≠ 0). In vacuum, the source σ(dG/dx) supports an energy density distribution that supplies a repelling pressure gradient outside of discrete isolated massive systems. Surprisingly, the same source becomes attractive in linearized perturbations, and its linear pressure gradient opposes the kinetic terms in the Jeans stability criterion.

Generalised graded interpolation

We develop an initial study of interpolation for graded consequence relations, which are many-valued consequence relations that arise in connection to many-valued / fuzzy logics. While in general consequence relations represent a foundational structure that supports the mathematical study of reasoning, their graded / many-valued upgrade provides mathematical foundations specifically for approximate reasoning. Our study is developed at the abstract level of institution theory of Goguen and Burstall which is an axiomatic and categorical approach to model theory. It consists of a development of new concepts – that are many-valued – of interpolation, but also of Robinson joint-consistency and Beth definability, and of results that recover at the many-valued truth level the causality relations between these and interpolation, as known from the classical binary context.

Preparing Precollege Students for the Second Quantum Revolution with Core Concepts in Quantum Information Science

After the passage of the U.S. National Quantum Initiative Act in December 2018, the National Science Foundation (NSF) and the Office of Science and Technology Policy (OSTP) recently assembled an interagency working group and conducted a workshop titled “Key Concepts for Future Quantum Information Science Learners” that focused on identifying core concepts for future curricular and educator activities to help precollege students engage with quantum information science (QIS). Helping precollege students learn these key concepts in QIS is an effective approach to introducing them to the second quantum revolution and inspiring them to become future contributors in the growing field of quantum information science and technology as leaders in areas related to quantum computing, communication, and sensing. This paper is a call to precollege educators to contemplate including QIS concepts into their existing courses at appropriate levels and get involved in the development of curricular materials suitable for their students. Also, research shows that compare-and-contrast activities can provide an effective approach to helping students learn. Therefore, we illustrate a pedagogical approach that contrasts the classical and quantum concepts so that educators can adapt them for their students in their lesson plans to help them learn the differences between key concepts in quantum and classical contexts.

New Challenges for Classical and Quantum Probability

The discovery that any classical random variable with all moments gives rise to a full quantum theory (that in the Gaussian and Poisson cases coincides with the usual one) implies that a quantum–type formalism will enter into practically all applications of classical probability and statistics. The new challenge consists in finding the classical interpretation, for different types of classical contexts, of typical quantum notions such as entanglement, normal order, equilibrium states, etc. As an example, every classical symmetric random variable has a canonically associated conjugate momentum. In usual quantum mechanics (associated with Gaussian or Poisson classical random variables), the interpretation of the momentum operator was already clear to Heisenberg. How should we interpret the conjugate momentum operator associated with classical random variables outside the Gauss–Poisson class? The Introduction is intended to place in historical perspective the recent developments that are the main object of the present exposition.

Telling the Wave Function: An Electrical Analogy

The double nature of material particles, i.e., their wave and corpuscular characteristics, is usually considered incomprehensible, as it cannot be represented visually. It is proposed to the student, in introductory courses, as a fact justified by quantum interference experiments for which, however, no further analysis is possible. On this note, we propose a description of the wave function in terms of a simple electrical analogy, which reproduces at least some of its essential properties. Our aim is to provide a cognitive representation of an analogical type: starting from a classical context (electrical circuits) and introducing in an appropriate way the notions of “wave” and “particle”, we show how typically quantum properties such as delocalization and entanglement emerge in a natural, understandable, and intuitive way.

Kratos and Other Forms of Power in the Two Constitutions of the Athenians

Abstract What did kratos imply in the classical democratic context? Focusing on the two Constitutions of the Athenians traditionally attributed to Xenophon and Aristotle respectively, this article explores differences among kratos and three proximate terms: archē (de facto governance or magistracy), kuros (authority, perceived as legitimate), and dēmagōgia (leadership). With Benveniste and Loraux, it argues that kratos specifically signalled ‘superiority’ or ‘predominance’, as revealed in combat or other form of contest. Dēmokratia thereby connoted the forceful predominance of the dēmos (‘assembly’, ‘collective common people’) over the rest of the community, including office-holders (archontes, archai) and political leaders (dēmagōgoi). The association of kratos with force directs attention to the martial underpinnings of classical demotic authority, incidentally highlighting a weakness in modern democracy: the dēmos’ lack of kratos over the political elite when that elite controls military and police power.

Collaborative truck-and-drone delivery for inventory-routing problems

With the retail market more competitive than it has ever been and with profit margins razor-thin, it has become of the essence that business operations are conducted as cost-efficiently as possible. With traditional methods exhausted, companies now see it worthwhile to explore fundamentally paradigm-shifting methods to create savings. For the logistics industry, one such approach is the incorporation of unmanned aerial vehicles (UAVs), or drones, into the delivery cycle, whose per-mile transportation costs are much lower than those of trucks, the traditional mode of transportation for deliveries. Yet despite the long-standing promise of drones to revolutionize the supply chain, realistic proposals for the exact ways in which UAVs would be introduced into delivery operations have only recently begun to appear in the operations research literature. Particularly noteworthy among these proposals is the concept of collaborative truck-and-drone operation, which captures the advantages of each of the two modes of delivery involved while attenuating their respective downsides. Over the past five years, collaborative delivery has been studied extensively in the classical contexts of the traveling salesman problem and the vehicle-routing problem. In this paper, we offer a first incursion into studying the incorporation of tandem truck–drone delivery into the inventory-routing problem (IRP)–a more realistic and more challenging operations model. After presenting a mixed integer-linear programming formulation for the IRP with drone (IRP-D), we propose an exact branch-and-cut solution approach for it. Additionally, a heuristic for the problem is designed based on the solution of the basic (i.e., droneless) IRP. Extensive computational results show that the heuristic is effective both as a standalone algorithm and as a warm-starting agent for the branch-and-cut IRP-D algorithm. We also demonstrate the contrast between the IRP-D and the basic IRP.

The Feeling of Sound: Music Curating, Performing and Connecting with and through Music

Long story short In this research exposition, I would like to invite the reader on a journey of discovery in the field of classical music presentation. Over the last 50 years there have been many suggestions on how to allow the professional field of classical music to develop alongside its time and people. To get a new perspective on the topic, I approach ASMR as a connected topic, investigate it under the aspect of listening and then make a transfer to my professional practice. ASMR stands for autonomous sensuous meridian response and is describing a special kind of sensory perception. I study ASMR as way of perception and as well as a YouTube / media phenomenon. My research question is: What can I learn from ASMR (about contemporary audience’s perception of sound) and how can I integrate this in my artistic practice? When I talked to colleagues or teachers from a classical music context, ASMR appeared to them at first as something bizarre and insignificant. Still, it has millions of followers on the internet. A large number of followers is not necessarily an indicator of artistic quality, but it can certainly be an argument to arouse curiosity. After all, the number of followers towards a subject does say something about its appeal or the ability to grasp people. By comparing ASMR to synaesthesia, I want to focus on perception and sensuousness but also explore common traits and differences of the two phenomena as both neurological phenomenon and the social (artistic) movement. An analysis and five experiments involving technological and dramaturgical tools often used in ASMR, leads to the final chapter: the artistic implementation. During the two years of my master studies, I designed two performance concepts, in which I applied the insights I gained throughout this research. A documentation of the process and a more elaborate explanation of the concept are to be found in chapter 4. In the end of this exposition, I summarize the conclusions of the research I made on a general and on a personal level. In order to acquire more information as well as a wider view, I have reached out to literature within the fields of sociology, (social) history, psychology, neuroscience and philosophy . During my years of studies in music, music pedagogic, historical and innovative performance practice, I quenched my thirst for knowledge about the past and now I am hungry to learn about the now and the future.

God and Self in Confessiones IV and Beyond: Therapeia, Self-Presence, and Ontological Contingency in Augustine, Seneca, and Heidegger

This article investigates Augustine’s reflection on the death of his friend in Confessiones IV. A critical treatment of this passage discloses the three key themes which will form the main substance of the analysis: self-presence, the contingency of being, and divine absence. Integrating philosophical and theological methodologies with an historical-critical treatment of Augustine’s work, this article relates Augustine’s insights to his foregoing classical context and his reception in posterity, with particular attention to Lucius Annaeus Seneca (ca. 4 BCE-65 CE) and Martin Heidegger (1889-1976). This investigation shows that these three figures are connected by an appreciation of how self-presence and ontological instability are constant facets of human life, though easily neglected. Each advocates a curriculum of philosophical training, whereby one learns to pacify the mind by an awareness of the true nature of mundane reality. This research contributes to the renewed appreciation of how the therapeutic aspects of classical philosophy influenced early Christian authors; illuminates a key episode in Augustine’s life en route to his conversion to Christianity; and raises questions about the “apophatic” dimensions of Augustine’s theology and anthropology.