FRBs Lensed by Point Masses. II. The Multipeaked FRBs from the Point View of Microlensing

The microlensing effect has developed into a powerful technique for a diverse range of applications including exoplanet discoveries, structure of the Milky Way, constraints on MAssive Compact Halo Objects, and measurements of the size and profile of quasar accretion disks. In this paper, we consider a special type of microlensing events where the sources are fast radio bursts (FRBs) with ∼milliseconds (ms) durations for which the relative motion between the lens and source is negligible. In this scenario, it is possible to temporally resolve the individual microimages. As a result, a method beyond the inverse ray shooting method, which only evaluates the total magnification of all microimages, is needed. We therefore implement an algorithm for identifying individual microimages and computing their magnifications and relative time delays. We validate our algorithm by comparing to analytical predictions for a single microlens case and find excellent agreement. We show that the superposition of pulses from individual microimages produces a light curve that appears as multipeaked FRBs. The relative time delays between pulses can reach 0.1–1 ms for stellar-mass lenses and hence can already be resolved temporally by current facilities. Although not yet discovered, microlensing of FRBs will become regular events and surpass the number of quasar microlensing events in the near future when 104−5 FRBs are expected to be discovered on a daily basis. Our algorithm provides a way of generating the microlensing light curve that can be used for constraining stellar-mass distribution in distant galaxies.

Food Choice With Economic Scarcity and Time Abundance: A Qualitative Study

Consumers with low income in the United States have higher vulnerability to unhealthy diets compared with the general population. Although some literature speculates that scarcity is an explanation for this disparity, empirical evidence is lacking. We conducted a qualitative study of food choice to explore whether scarcity-related phenomena, such as tunneling and bandwidth tax, may contribute to unhealthy dietary choices. We used participant-driven photo elicitation ( n = 18) to investigate the food choice behaviors of individuals living in the greater Boston area who met the federal guidelines for poverty. Participants took photos at the point of food acquisition for 1 month, after which we interviewed them using a semistructured interview guide with the photos as prompts. Thematic coding was used for analysis. Respondents had relative time abundance. Two major themes emerged: participants used a set of strategies to stretch their budgets, and they highly prioritized cost and preference when making food choices. The extreme focus on obtaining food at low cost, which required time and effort, was suggestive of tunneling. We found no evidence of the bandwidth tax. Our findings raise the hypothesis of scarcity as a continuum: when individuals experience multiple resource constraints, they experience scarcity; whereas people with very limited finances and relative time abundance may instead be in a prescarcity condition, with a hyperfocus on a scarce resource that could lead to tunneling as constraints increase. Additional studies are needed to understand whether and how tunneling and bandwidth tax emerge, independently or together, as people face different levels and types of scarcity.

Kinematics of the viscous filament during the droplet breakup in air

The dripping regime in the vicinity of droplet breakup is analyzed concerning the evolution of the filament’s neck and its corresponding thinning velocity. Three flow regimes are observed as the relative time decreases: (i) a monotonous increase of the neck’s thinning velocity, where inertia and capillarity are balanced, (ii) a transition region characterized by the equilibrium between inertia, capillarity, and viscous forces, where the thinning velocity varies non-monotonically with the relative time and (iii) the final pinch-off regime, where velocity decreases or oscillates around a constant value. Based on the correlation between experimental data and numerics, the distribution of the zeta - coefficient (defined as the non-dimensional second invariant of the velocity gradient) on the droplet’s profile is used to quantify the ratio between elongation and rotation of the fluid at the interface. The regions dominated by extension, where pure elongation is located at zeta = 1 , are determined. One main result of this study is the confirmation that distribution of the zeta - coefficient is a relevant parameter to analyze and to quantify the breakup process. This result has the potential of developing novel techniques and more precise procedures in determining the interfacial rheology of viscous and complex fluids.

SYNTACTIC TIME AND POETIC TEXT

Монография Т.Е. Шаповаловой посвящена осмыслению категории синтаксическое время. Время как синтаксическая категория и обязательный компонент предикативности исследуется на материале поэтического текста, в котором все грамматические элементы преображаются. В частности, синтаксемы и субстантивные обороты – носители временнóй семантики получают дополнительные субъективно-модальные оттенки, событийные коннотации, сопутствующие созначения (пространственные, условные и др.). Рассматриваются также такие принципиальные для понимания синтаксической проблемы времени теоретические вопросы, как абсолютное и относительное время, временнáя определенность и временнáя неопределенность, предикативные свойства синтаксемы, субстантивного оборота и др. Monograph by prof. T.E. Shapovalova is devoted to understanding of the category of syntactic time. Time as a syntactic category and an obligatory component of predicativity is considered on the material of a poetic text, in which all grammatical elements are transformed - in particular syntaxemes as the carriers of temporal semantics receive additional subjective-modal shades, event connotations, and accompanying connotations (spatial, conditional, etc.). We also considered such fundamental for understanding of the syntactic problem of time as absolute and relative time, temporal definiteness and temporal uncertainty, predicative properties of substantive turnover, etc.

Determination of time evolution of the gravitational constant in the framework of Brans-Dicke Theory: An easy wa

The present article demonstrates a very simple mathematical way to determine the time-dependence of the dynamical gravitational constant () in the framework of the Brans-Dicke theory of gravity. Brans-Dicke field equations, for a matter-dominated, pressure-less and spatially flat universe with homogeneous and isotropic space-time, have been used for this formulation. The gravitational constant () is the reciprocal of the Brans-Dicke scalar field (). Using a simple ansatz, which represents the Brans-Dicke scalar field () as a function of time, the possible values of a constant parameter (constituting the ansatz) have been calculated with the help of the field equations, using the values of some cosmological parameters at the present time. The values of that parameter (belonging to the ansatz) lead to the conclusion that the scalar field () decreases and consequently the gravitational constant () increases with time. The value of the relative time-rate of change of the gravitational constant (i.e., ) has also been estimated and this quantity has been found to be independent of time. Time-dependence of and has been depicted graphically for all values of the parameter belonging to the ansatz. The novel features of this study are that the gravitational field equations did not have to be solved, unlike other studies, to arrive at the results and the mathematical scheme for calculations is extremely easy in comparison to other recent studies in this regard.

Towards a more objective time standard in competitive rowing

Rowing needs a standardized Gold Medal Standard (GMS) to clearly compare performance across boat classes in competition. Here, we report a method to factor out environmental effects, developing a fairer GMS for individual rowing events. We used results from World Rowing Championships and Olympics Games (2005–2016) to calculate the difference between the fastest winning time of the day and other event winning times on the same day. From this, we calculated a prognostic GMS time for each event via repeated k-fold cross-validation linear regression. Then, we compared these values with the 10-year average winning time and the World Best Time (WBT). We repeated this process to develop prognostic podium standard (PS) times. The prognostic GMS times (RMSE = 9.47; R 2 = 0.875) were universally slower than the WBT (current GMS) by 6.2 s on average but faster than the 10-year average by 12.3 s. The prognostic PS times (RMSE = 10.5; R 2 = 897) were also slower than the WBT but faster than the 10-year average, by 12.2 and 6.3 s respectively. Our time-difference prediction model based on historical data generates non-outlier prognostic times. With the utilization of relative time difference, this approach promises a selection standard independent of environmental conditions, easily applicable across different sports.

PLUPERFECT – ABSOLUTE, RELATIVE OR ABSOLUTE-RELATIVE TEMPORAL FORM?

The article is devoted to the problem of grammatical status of pluperfect forms of German and Ukrainian languages. The study differentiates the views of scientists on pluperfect forms in terms of their relative or absolute interpretation. The definition of the pluperfect with the future temporal reference is given, confirmed by applied representations and analysis of the studied units in the sentence structure. From the point of view of traditional linguistic interpretation, pluperfect is a form that expresses either “precedence over another past action” or “distant past”. However, in this study, we look at new meanings of this grammar: “present” or “future”.The article raises the problem of the futural orientation of pluperfect forms, based on two positions: when pluperfect is used in the sense of “past” in relation to another past action. That is, when this gram is in opposition to its conventional meaning; when the plusquamperfect expresses the meaning of “counterfactual” with the future temporal reference, when the subject of the statement knows that in the real world certain actions cannot be realized because they contradict the objective laws of human existence. The use of the pluperfect forms in such constructions indicates that language not only does not limit us by means of expressing real knowledge about the world, but also provides such for the reproduction of hypothetical, unreal or counterfactual statements.It is concluded that from the point of view of temporality, the conjunctive forms of the pluperfect are timeless and can express the action that occurs at the time of speech, occurred (or could occur) before the moment of speech or will occur after the moment of speech, the temporal nature of the verbal form recedes into the background. It is proposed to consider plusquamperfect as an absolute-relative time form.Key words: pluperfect, absolute time, relative time, moment of speech, counterfactuality. Статтю присвячено актуальній проблемі граматичного статусу плюсквамперфектних форм німецької та української мов. У дослідженні диференційовано погляди науковців щодо плюсквамперфектних форм із боку їх відносної чи абсолютної інтерпретації. Подається визначення плюсквамперфекта з майбутньою часовою рефе-ренцією, підтверджене прикладними репрезентаціями й аналізом досліджуваних одиниць у структурі речення. З боку традиційного лінгвістичного трактування плюсквамперфект – це форма, яка виражає або «передування щодо іншої минулої дії», або «віддалене минуле». Однак у дослідженні звертаємо увагу на нові значення цієї гра-меми: «теперішнє» чи «майбутнє».У статті висувається проблема футуральної спрямованості плюсквамперфектних форм, виходячи з двох позицій: коли плюсквамперфект вживається в значенні «післяминуле» щодо іншої минулої дії, тобто коли ця грамема опозиціонує своєму загальноприйнятому значенню; коли плюсквамперфект виражає значення «контр-фактичність» із майбутньою часовою референцією – суб’єкт висловлення знає, що в реальному світі певні дії не можуть бути реалізовані, оскільки суперечать об’єктивним законам людського існування. Вживання плюсквам-перфектних форм у подібних конструкціях свідчить про те, що мова не лише не обмежує нас засобами вираження реальних знань про світ, а й надає такі для відтворення гіпотетичних, ірреальних чи контрфактичних висловлень.Зроблено висновок, що з позиції темпоральності форми плюсквамперфекта кон’юнктива є позачасовими й можуть виражати дію, що відбувається в момент мовлення, відбувалася (чи могла відбутися) раніше моменту мовлення або відбудеться після моменту мовлення, оскільки в зіставленні часу й способу переважає спосіб дієслова, а часовий характер вербальної форми відходить на другий план. Запропоновано розглядати плюсквампер-фект як абсолютно-відносну часову форму.Ключові слова: плюсквамперфект, абсолютний час, відносний час, момент мовлення, контрфактичність