Classical Time Research Articles

The dynamic universe: realizing the potential of classical time domain and multimessenger astrophysics

In parallel with the multi-messenger revolution, major advances in time-domain astronomy across multiple science disciplines relevant to astrophysics are becoming more urgent to address. Aside from electromagnetic observations of gravitational wave events and explosive counterparts, there are a number of “classical” astrophysical areas that require new thinking for proper exploration in the time domain. How NASA, NSF, ESA, and ESO consider the 2020 USA Decadal Survey within the astronomy community, as well as the worldwide call to support and expand time domain and multi-messenger astrophysics, it is crucial that all areas of astrophysics, including stellar, galactic, Solar System, and exoplanetary science participate in the discussion, and that it not be made into an exclusive preserve of cosmological, high-energy, explosive and transient science. Time domain astronomy is used to explore many aspects of astrophysics–particularly concerning ground- and space-based mission science goals of exploring how the Universe works, understanding how did we get here, and are we alone. Time domain studies are already built into the core operations of many currently operating and future space telescopes (e.g., Roman, PLATO) as well as current and planned large areal ground-based surveys (e.g., Rubin). Time-domain observations designed for one scientific purpose, also lead to great discoveries in many other science areas. The recent advent of user-friendly hardware, software, observational approaches, and online data infrastructure has also helped make time domain observations especially suitable and appealing for citizen science projects. We provide a review of the current state of TDAMM alerts and observational protocols, revealing a wide array of software and applications, much of which is incompatible. Any conversation regarding TDAMM astrophysics should include all aspects of the field, including those aspects seen as classical applications.

Celebrating diversity: The origins and pathways of three support-verb constructions

Support-verb constructions are combinations of a verb and a noun that fill the predicate slot of a sentence, such as to make a suggestion in I made the suggestion that she join us. While qualifying as semantic-lexemic phrasemes (collocations and idioms) in Mel’čuk’s Sens-Texte framework, they sit at the lexicon-syntax interface. They qualify as verbal multi-word expressions lexically speaking and form complex predicates syntactically. In classical and post-classical Greek, support-verb constructions form an internally heterogenous group of constructions, yet one that has existed since the earliest records of the language and survives into the modern variety. The present chapter capitalises on the over 2000 years of continuous written history of Greek, and the internal heterogeneity of the group of support-verb constructions, in that it investigates the origins and pathways of three members of this group in the literary (Thesaurus Linguae Graecae) and documentary (Duke Database of Documentary Papyri) corpora of Greek. The bulk of documentary texts dates from the 3rd c. BC onwards, whereas the earliest literary texts date from around the 8th c. BC. The variety of sources allows us to trace the three structures of interest through the centuries in varying environments and thus to trace traditions and independent developments. δίκην δίδωμι dikēn didōmi existed as a collocation ‘to give judgement(s)’ from archaic times and into the medieval period, in classical times, the idiom δίκην δίδωμι dikēn didōmi ‘to pay the price for one’s actions’ arose and became indexed for the technical and higher registers. In χάριν ἀπολαμβάνω kharin apolambanō ‘to receive a favour’, the prototypical compound ἀπολαμβάνω apolambanō seems to be diatopically and subsequently diastratically indexed but retreats into the higher registers after the classical period; the canonical simplex verb λαμβάνω lambanō predates it in early classical verse and postdates it. προσέχω τὸν νοῦν prosekhō ton noun exists as an idiom especially in medical discourse from at least classical times onwards but in parallel also as a pragmateme from archaic times onwards. Support-verb constructions are a pattern that is considered near universal in languages, such that especially the methodological tool of the support-verb-construction field developed and drawn upon in this chapter is transferable beyond Greek.

CRITICAL ANALYSIS OF THE HISTORICAL DEVELOPMENT OF ETHICAL-LEGAL DISCOURSE ON CLIMATE CHANGE MANAGEMENT

This paper has focused on the historical development of ethical and legal thought on climate change. The study has aimed to historically locate ethical and legal basis on environmental with the urge to overcome climate change, to establish the advent of climate change reality and the management mechanism, and finally bring about the intersection between ethics and law on climate change management. The study has traced philosophical ideas on the environment from ancient and classical times through the medieval, renaissance, modern, and contemporary periods. It has also explored the African perspectives on environmental issues and considered climate change science’s legal and ethical dimensions from the 19th century to the present. Here various approaches to climate change management mechanisms such as anthropocentrism, ecocentrism, biocentrism, regenerative paradigms, climate justice, and holistic approaches have been discussed, thus placing into perspective what has been down. To achieve this goal, the study was guided by Husserl’s Phenomenological Method and theory which has analyzed the climate change discourse throughout the discourse. The discourse has culminated with bringing out clarity on the complex web of ideologies, power dynamics, and institutional structures that shape responses to the climate change crisis and create sustainable mechanisms.

Lessons learned from an fMRI-guided rTMS study on performance in a numerical Stroop task.

The Stroop task is a well-established tool to investigate the influence of competing visual categories on decision making. Neuroimaging as well as rTMS studies have demonstrated the involvement of parietal structures, particularly the intraparietal sulcus (IPS), in this task. Given its reliability, the numerical Stroop task was used to compare the effects of different TMS targeting approaches by Sack and colleagues (Sack AT 2009), who elegantly demonstrated the superiority of individualized fMRI targeting. We performed the present study to test whether fMRI-guided rTMS effects on numerical Stroop task performance could still be observed while using more advanced techniques that have emerged in the last decade (e.g., electrical sham, robotic coil holder system, etc.). To do so we used a traditional reaction time analysis and we performed, post-hoc, a more advanced comprehensive drift diffusion modeling approach. Fifteen participants performed the numerical Stroop task while active or sham 10 Hz rTMS was applied over the region of the right intraparietal sulcus (IPS) showing the strongest functional activation in the Incongruent > Congruent contrast. This target was determined based on individualized fMRI data collected during a separate session. Contrary to our assumption, the classical reaction time analysis did not show any superiority of active rTMS over sham, probably due to confounds such as potential cumulative rTMS effects, and the effect of practice. However, the modeling approach revealed a robust effect of rTMS on the drift rate variable, suggesting differential processing of congruent and incongruent properties in perceptual decision-making, and more generally, illustrating that more advanced computational analysis of performance can elucidate the effects of rTMS on the brain where simpler methods may not.

Resolving degeneracies in Google search via quantum stochastic walks

The internet is one of the most valuable technologies invented to date. Among them, Google is the most widely used search engine. The PageRank algorithm is the backbone of Google search, ranking web pages according to relevance and recency. We employ quantum stochastic walks (QSWs) with the hope of bettering the classical PageRank (CPR) algorithm, which is based on classical continuous time random walks. We implement QSW via two schemes: only incoherence and dephasing with incoherence. PageRank using QSW with only incoherence or QSW with dephasing and incoherence best resolves degeneracies that are unresolvable via CPR and with a convergence time comparable to that for CPR, which is generally the minimum. For some networks, the two QSW schemes obtain a convergence time lower than CPR and an almost degeneracy-free ranking compared to CPR.

An Information Fusion Technique for Prognosticating Future Air Passenger Trends

The aviation industry is constantly changing and to keep up with the trends of air passengers we need predictive models. In this paper, we explore the use of Information Fusion methodologies and classical time series techniques to forecast how many passengers will be traveling by air. Predicting passenger demands is a task, due to various factors that influence travel patterns. The existing models often struggle to capture the dynamics in this field so it's crucial to develop accurate forecasting methods. By leveraging information fusion techniques like smoothing and Autoregressive Integrated Moving Average (ARIMA) our research creates models based on historical data of air passenger volumes. These techniques combine machine learning algorithms and time series analysis to identify dependencies and patterns in the dataset. Through evaluations and comparative analyses, our proposed models demonstrate promising capabilities in forecasting future air passenger volumes. Proof-of-concept experiments based on 5-fold cross-validation demonstrate the efficacy of the proposed approach in capturing underlying trends and seasonality within the dataset.

A comparative study of symbolic aggregate approximation and topological data analysis

<p>The movement of stocks is often perceived as random due to the complex interactions between different stocks and the inherently chaotic nature of the market. This study investigated the similarity in stock movements across multiple industry sectors in Europe. Specifically, we applied topological data analysis (TDA) to analyze stock time series data and compared the results with those obtained using an expanded form of a more classical time series analysis method, symbolic aggregate approximation (SAX). Our findings indicated that while TDA offered detailed insights into "local" stock movements, SAX was more effective in capturing broader trends in financial markets, where less detail was required, making it suitable for portfolio optimization. We also presented an extension of SAX that incorporated volatility measures, improving its performance in highly volatile markets.</p>

Politico-Cultural Exigencies and the Rise of Rhetoric in Classical Greece

Did rhetoric naturally evolve from the inherent power and potential of language, or were specific political and cultural conditions instrumental in driving its development in classical Greece? This paper explores this question by adopting a historical approach to rhetoric and a rhetorical approach to history. It draws on the perspectives of sophists such as Gorgias, the anonymous author of “Dissoi Logoi,” and Isocrates, as well as the rhetorical philosophical orientations of Plato and Aristotle. In conducting this study, I employ a methodological review approach that relies on the scholarship of rhetoric and rhetorical history and critically analyse available sources and the arguments developed in the field. Through this approach, I argue that the emergence of rhetoric in classical times was prompted by several exigent factors, including humanism, democracy, education, literacy, and legal practices. Therefore, theorizing and practicing rhetoric beyond the cultural-political context is inherently partial and incomplete.

A Multianalytical Approach to Identifying the White Marbles Used in Roman Imperial Sculptures from Tarraco (Hispania)

A selection of the most outstanding white marble sculptures from Tarraco has been archaeometrically studied to know more about the marble sources and their respective artistic workshops. All are imperial portraits of the 2nd century AD (Trajan, Hadrian, Lucius Verus and Marcus Aurelius) and a thoracata bust assigned to Hadrian, found on display at the National Archaeological Museum of Tarragona (MNAT). The well-established multimethod approach, combining petrography, cathodoluminescence, C and O isotopes and Sr and Mn trace element composition, has revealed the use of different very fine- to fine-grained marbles of the highest quality exploited in classical times. In contrast to what was thought until now, in which all the pieces had been assigned to Luni-Carrara, this present study identifies the use of two varieties of the recently discovered site of Göktepe near Aphrodisias and Paros-lychnites marbles, being Carrara, in minority. This study confirms the importance of strontium concentration and the contribution of cathodoluminescence to distinguish Göktepe from Carrara marble, while carbon and oxygen isotopes were crucial for the identification of Cycladic marble. Finally, in line with recent published interdisciplinary studies, the marble provenance forces us to rethink the discourse on the use of marble, its sculptural workshops and its distribution in this temporal context.

Konsep MujᾹdalah dalam Al-Qur’an Kontekstualisasi Klasik dan Kontemporer (Kajian terhadap Ayat-ayat Jadal)

This thesis discusses the concept of Mujādalah in the Al-Qur'an in classical and contemporary times. The problem that is the focus of this thesis research is that the author clearly explains the concept of mujādalah in classical and contemporary times, including several verses that discuss the concept of mujjadilah as well as the opinions of several mufassirs regarding the concept of mujādalah. That's why the author raised it as a scientific research. The method used in this research is descriptive analysis method. By using the Al-Qur'an, source books, and books of interpretation. As supporting data and comparative data, the author presents the works of scholars in this thesis. This research was conducted with the aim of knowing the concept and ethics of implementing mujjadi according to the Koran and its effectiveness as a method of da'wah. The existence of Islamic da'wah nowadays has a very static understanding among the majority of society. If it is said to be da'wah when there is a speaker, the means and material presented are full of humor or have lots of jokes in it. Meanwhile, when someone presents material, of course the material in question is more focused on certain areas and issues, but the majority of people tend not to want to listen or are even completely indifferent. The classical and modern views of da'wah should be synchronized again, so that the targets and objectives of da'wah are in the context of how the material presented can be reached and accepted by society, so that change in society as the final target is achieved.

A Newly Discovered Coin from Kietis Featuring Acheloios Kalykadnos

Fairly recently, a small bronze coin measuring just 9mm and weighing a mere 0.88g came to market via Bertolami e-Auction 93 (2021), lot 341 (Figure 1), which I will argue dates to the first half of the 4th century BC. On the obverse we find the head of Hermes, who is part of Acheloios’ classical retinue, wearing petasos with head to right, all surrounded by a border of dots. On the reverse we find the forepart of Acheloios (of the Kalykadnos) to right, KIH above, and crescent behind, with points oriented away from Acheloios touching the outer edge of the flan. The coin was tentatively attributed to Kietis by the cataloguing numismatist, and in this essay I’d like to solidify that attribution while discussing the importance of the coin. In my estimation, this coin is particularly noteworthy for two reasons: (1) It is one of the earliest—if not the earliest—attestations of the Kietis region and helps solidify the existence of the ethnic in classical times; and, (2) It is a completely new type in the corpus of Acheloios coins, and the first and only known representation of Acheloios of the Kalykadnos—the largest river of Cilicia, ‘whose mighty stream washes the towers of the city walls.’

Policy Initiatives for enhancing domestic availability of vegetable oils in India

The backbone of several agricultural economies from classical times assume a prominent role by providing access to nutrition through protein and oil to humans and livestock beside usage in the industrial sector and also a life line for providing livelihood and employment to those involved in the processing sector. The country which evidenced self-sufficiency in oilseeds during early nineties and ultimately gained the status of the world's largest importer, with import of 14.28 million tonnes during 2021-22. e Compound Annual Growth Rates (was used to assess the performance of annual oilseeds during 2000-01 to 2020-21. It was evidenced that the CAGR was positive for all the components. The power of technology operational at the farm level, paved way for sustained production, which is due to the technology outputs from the NAREES/AICRP on oilseeds besides the driving forces initiated by the Government of India. For further reducing import dependency, policy instruments eviz. Seed production, technology assemblage, linkages and convergence, providing incentives, promoting PM-FME.

Classical and quantum elliptical billiards: Mixed phase space and short-range correlations in singlets and doublets

Billiards are flat cavities where a particle is free to move between elastic collisions with the boundary. In chaos theory, these systems are simple prototypes. The conservative dynamics of a billiard may vary from regular to chaotic, depending only on the shape of the boundary. This work aims to shed light into the quantization of classically chaotic systems. We present numerical results on classical and quantum properties in two bi-parametric families of billiards, namely Elliptical Stadium Billiard (ESB) and Elliptical-C3 Billiards (E-C3B). Both families entail elliptical perturbations of chaotic billiards with originally circular sectors on their borders. Our numerical calculations provide evidence that these elliptical families may exhibit a mixed classical dynamics, identified by the chaotic fraction of the phase space, the parameter χc<1. We use this quantity to guide our analysis of quantum spectra. We explore the short-range correlations through nearest neighbor spacing distribution p(s), revealing that in the mixed region of the classical phase space, p(s) is well described by the Berry–Robnik–Brody (BRB) distributions for the ESB. In agreement with the expectation from the so-called ergodic parameter α=tH/tT, the ratio between the Heisenberg time and the classical diffusive-like transport time. Our findings indicate the possibility of quantum dynamical localization when α<1. For the E-C3B family, the eigenstates can be split into singlets and doublets. BRB successfully describes p(s) for singlets as the previous family in the mixed region. However, for doublets, new distributions recently introduced in the literature come into play, providing descriptions for p(s) with a focus on cases where χc=1. We observed that as χc decreases, the p(s) distributions simultaneously deviate from the Gaussian Orthogonal Ensemble (GOE) for singlets, and Gaussian Unitary Ensemble (GUE) for doublets.

Clock synchronization with pulsed single photon sources

Photonic quantum technology requires precise, time-resolved identification of photodetection events. In distributed quantum networks with spatially separated and drifting time references, achieving high precision is particularly challenging. Here we build on recent advances of using single-photons for time transfer and employ and quantify a fast postprocessing scheme designed to pulsed single-photon sources. We achieve an average root mean square synchronization jitter of 3.0 ps. The stability is comparable to systems with Rb vapor cell clocks with 19 ps at 1 s integration time, in terms of Allan time deviation. Remarkably, our stability is even better than classical high-precision time transfer, like the White Rabbit protocol, although we use significantly less signal (single-photon level). Our algorithms allow local processing of the data and do not affect the secure key rate. It compensates substantial clock imperfections from crystal oscillators and we foresee great potential for low signal scenarios. The findings are naturally suited to quantum communication networks and provide simultaneous time transfer without adding hardware or modifying the single-photon sources.

An active colloidal system showing parallels to a time crystal

The spontaneous breaking of symmetries is a widespread phenomenon in physics. When time translational symmetry is spontaneously broken, an exotic nonequilibrium state of matter in which the same structures repeat themselves in time can arise. This state, known as ‘time crystal’, attracted a lot of interest recently. Another relatively new research area deals with active matter. Materials consisting of colloidal particles that consume energy from their environment and propel themselves forward can exhibit intriguing properties like superfluidity that were previously known only from quantum-mechanical systems. Here, we bring together these—at first glance completely different—research fields by showing that self-propelled colloidal particles show parallels to classical continuous time crystals. We present a state diagram showing where this state of matter arises. Furthermore, we investigate its properties and analyze the interactions between the particles leading to the dynamics.

Quantization of spherically symmetric loop quantum gravity coupled to a scalar field and a clock: the asymptotic limit

We continue our work on the study of spherically symmetric loop quantum gravity coupled to two spherically symmetric scalar fields, one which acts as a clock. As a consequence of the presence of the latter, we can define a true Hamiltonian for the theory. The spherically symmetric context allows to carry out precise detailed calculations. Here we study the theory for regions of large values of the radial coordinate. This allows us to define in detail the vacuum of the theory and study its quantum states, yielding a quantum field theory on a quantum space time that makes contact with the usual treatment on classical space times.

Inverted U-shaped association between bacillary dysentery and temperature: A new finding using a novel two-stage strategy in multi-region studies.

Bacillary dysentery (BD) has brought a significant public health concern in China. Temperature is one of the main factors affecting BD incidence. Due to the largely different temperature ranges between regions, the classic multi-region time series studies could only explore the relative temperature-BD association and showed that BD incidence is positively associated with relative temperature (i.e., temperature percentile), which does not conform to the laboratory knowledge that both high and low temperature interfere with the survival of bacteria. The association on relative temperature scale also limits the intuition of epidemiological meanings. A novel two-stage strategy was proposed to investigate the association between monthly temperature and BD incidence on the original temperature scale in 31 provinces, China. In the first stage, truncated polynomial splines, as the substitute of the common natural splines or B-splines in generalized additive models, were used to characterize the temperature-BD association on the original temperature scale in each province. In the second stage, a multivariate meta-analysis compatible with missing values was used to pool the associations. The classic strategy based on relative temperature was used as a reference. The average temperature-BD association presented a U-inverted shape, but not a monotonically increasing shape obtained using the classic strategy. This inverted U-shaped association conforms more to the laboratory knowledge and the original-scale association also provided an intuitive perspective and an easily explanatory result. Another advantage is that the novel strategy can extrapolate the province-specific association outside the observed temperature ranges by utilizing information from other provinces, which is meaningful considering the frequent incidences of extreme temperatures. The association between temperature and BD incidence presented a U-inverted shape. The proposed strategy can efficiently characterize the association between exposure and outcome on original scale in a multi-region study with largely different exposure ranges.

Unveiling the combined effects of neutral dynamics and electrodynamic forcing on dayside ionosphere during the 3–4 February 2022 “SpaceX” geomagnetic storms

Geomagnetic storms of G1-class were observed on 3 and 4 February 2022, which caused the loss of 38 out of 49 SpaceX satellites during their launch due to enhanced neutral density. The effects of storm-time neutral dynamics and electrodynamics over the American sector during this minor storm have been investigated using Global Positioning System—total electron content (TEC) and Global‐scale Observations of the Limb and Disk (GOLD) mission measured thermospheric composition and temperature. Results revealed an unexpected feature in terms of increase in O/N2 and depletion in TEC over the American low-latitudes. This feature is in addition to the classic storm time ionospheric variations of enhancement in ionospheric electron density in presence of enhanced O/N2 and an intense equatorial electrojet (EEJ). Further, significant morning-noon electron density reductions were observed over the southern mid-high latitudes along the American longitudes. Results from Multiscale Atmosphere-Geospace Environment (MAGE) model simulations elucidated storm-induced equatorward thermospheric wind which caused the strong morning counter electrojet by generating the disturbance dynamo electric field. This further explains the morning TEC depletion at low-latitudes despite an increase in O/N2. Sub-storm related magnetospheric convection resulted in significant noon-time peak in EEJ on 4 February. Observation and modelling approaches together suggested that combined effects of storm-time neutral dynamic and electrodynamic forcing resulted in significant ionospheric variations over the American sector during minor geomagnetic storms.

Comparative analysis of Fuzzy Regression and Fuzzy ARIMA models for forecasting real gross domestic product of Nigeria

Over the years, a number of studies have been conducted in terms of forecasting the real gross domestic product (GDP) of Nigeria. The GDP growth rate measures the annual growth rate in percentage of the monetary value of all finished goods and services made within a country. It is an important indicator of economic growth. This paper presents Fuzzy ARIMA and Regression to determine the interval of possibility for predicting the real GDP. The Fuzzy ARIMA (FARIMA) and Fuzzy Regression (FR) methods requires small size data as compared to the classical time series. Comparison between FARIMA and Fuzzy Regression with a threshold level of zero (ℎ=0) is performed by calibrating the models on existing data. The minimum values of the total spreads for FARIMA and FR are 0.791 and 4.077 respectively. In addition, the MAPE values for FARIMA is smaller than that of FR. Furthermore, the results indicate that the FARIMA gives a narrower interval of possibility for prediction than the FR.

Electric Field Effects on Curved Graphene Quantum Dots.

The recent and continuous research on graphene-based systems has opened their usage to a wide range of applications due to their exotic properties. In this paper, we have studied the effects of an electric field on curved graphene nanoflakes, employing the Density Functional Theory. Both mechanical and electronic analyses of the system have been made through its curvature energy, dipolar moment, and quantum regeneration times, with the intensity and direction of a perpendicular electric field and flake curvature as parameters. A stabilisation of non-planar geometries has been observed, as well as opposite behaviours for both classical and revival times with respect to the direction of the external field. Our results show that it is possible to modify regeneration times using curvature and electric fields at the same time. This fine control in regeneration times could allow for the study of new phenomena on graphene.