Centro Universitário Farias Brito: FB UNI Portal de Periódicos
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The postulate of vacuum as the medium of matter waves and the extension of the equivalence principle
No full textThe vacuum polarization described in quantum electrodynamics inspires the reconstruction of
the relationship between a vacuum and a particle. It is reasonable to amalgamate vacuum and
matter into one object: the metric space. Thus, the motion of matter can be described as the
propagation of the state of space in a vacuum, the vacuum being the medium through which the
matter wave propagates. The consequence of unifying a particle and vacuum with metric space
is that all the properties of the particle should be described as the intrinsic properties of the space.
By defining the affine curvature tensor symmetric part (electric field analogue) and an
antisymmetric part (magnetic field analogue, zero divergence), the energy density is proposed to
be proportional to the Kretschmann scalar, = ℏ /2, and the momentum similar to
electromagnetic momentum density 0 × ; a metric with a curvature proportional to /2 is
thus obtained. The equivalence of the torsion of the affine connection space with the angular
momentum of matter is then discussed. The quantized spin angular momentum eigenstate in
quantum mechanics is related to a connected torsional manifold. In the case of ℏ/2 spin, it
corresponds to a Möbius circle. It is remarkable that the two classified elementary particles,
bosons and fermions, correspond to the two types of topological manifolds, orientable and non
orientable manifolds.
The reinterpreted concept of matter, in the form of curved space, gives rise to the idea of
absolute space. The time dilation observed in the Global Positioning System, as predicted by
special relativity and depending on the velocity in relation to the “universal frame," provides
evidence of absolute space
The specificity of sequential statistical learning: Statistical learning accumulates predictive information from unstructured input but is dissociable from (declarative) memory for words
No full textLearning statistical regularities from the environment is ubiquitous across domains and species. It might support the earliest stages of language acquisition, especially identifying and learning words from fluent speech (i.e., word-segmentation). But how do the statistical learning mechanisms involved in word-segmentation interact with the memory mechanisms needed to remember words -- and with the learning situations where words need to be learned? Through computational modeling, we first show that earlier results purportedly supporting memory-based theories of statistical learning can be reproduced by memory-less Hebbian learning mechanisms. We then show that, in a memory recall task after exposure to continuous, statistically structured speech sequences, participants track the statistical structure of the speech sequences and are thus sensitive to probable syllable transitions. However, they hardly remember any items at all, with 82% producing no high-probability items. Among the 30% of participants producing (correct) high- or (incorrect) low-probability items, half produced high-probability items and half low-probability items~--- even while preferring high-probability items in a recognition test. Only discrete familiarization sequences with isolated words yield memories of actual items. Turning to how specific learning situations affect statistical learning, we show that it predominantly operates in continuous speech sequences like those used in earlier experiments, but not in discrete chunk sequences likely more characteristic of early language acquisition. Taken together, these results suggest that statistical learning might be specialized to accumulate distributional information, but that it is dissociable from the (declarative) memory mechanisms needed to acquire words and does not allow learners to identify probable word boundaries
Conversational Linguistic Features Inform Social-Relational Inference
No full textWhether it is the first day of school or a new job, individuals often find themselves in situations where they must learn and integrate into novel social relationships. However, the mechanisms through which individuals evaluate the strength and nature of these existing relationships – social-relational inference – remain unclear. We posit that linguistic features of conversations may help individuals evaluate social relationships and may be associated with social-relational inference. Leveraging a naturalistic behavioral experiment (57 adults; 34,735 observations), participants watched a mid-season episode of Survivor and evaluated the observed dyadic relationships between contestants. We employed novel person- and stimulus-focused approaches to 1) investigate social-relational inference similarity between participants, 2) examine the association between distinct linguistic features and social-relational inference, and 3) explore the relationship between early season conversation similarity and later perceived relationship formation. We found high pairwise participant response similarity across three experimental conditions, distinct associations between relational judgments and linguistic features, including semantic similarity, sentiment, and clout, and no evidence of an association between early conversation similarity and later friendship inference. These findings suggest that naturalistic conversational content is both a potential mechanism of social-relational inference and a promising avenue for future research
Ageing Advanced Capitalist Democracies: the new Electoral Politics of Economic Stagnation
No full textThe population of Advanced Capitalist Democracies (ACDs) has aged substantially in the last decades. Yet, we know little about the consequences of ageing for the electoral politics of economic performance. This article develops a novel theoretical framework linking ageing to lower economic growth in four interrelated steps: first, elderly voters care more about pensions, but less about childcare, family, and education policies; second, they are less likely to penalize governments for low growth and unemployment; third, grey power pushes governments to protect the growing share of budgets allocated to pensions at the expense of more growth-enhancing policies, most notably social and public investments, while also weakening policy responsiveness during recessions; fourth, this policy reallocation undermines economic growth. This theory is tested using multilevel and fixed-effects regressions, an instrumental variable approach, and causal mediation analysis on micro- and macro-level data across 21 ACDs from the 1960s onwards. The results show that ageing fundamentally alters the electoral politics of economic stagnation in ACDs
(Media Attention to) Misinformation can Undermine Trust in Scientists
No full textCould news coverage of misinformation be harmful? Across two studies on U.S. citizens, we examine whether news coverage of misinformation generates misperceptions and decreases levels of trust in information institutions (i.e., media, professors, and scientists) and whether its effects can be comparable to those of exposure to untrustworthy content. We rely on an online experiment using mock social media posts (Study 1, N = 1,670) and also on online behavioral tracking data paired with
over-time survey self-reports (Study 2, N = 804). Study 1 finds that exposure to both actual misinformation and the coverage of misinformation increases misperceptions, but does not decrease trust. Study 2 presents evidence that behaviorally tracked visits to untrustworthy sites and exposure to news coverage of misinformation —although relatively rare — do not affect misperceptions, but both predict lower levels of trust in scientists, with less consistent effects for media and university
professors. These results support concerns that not only misinformation but also its coverage contribute to epistemic uncertainty by eroding confidence in credible sources of knowledge, and warrant further inquiry in to the potential harms of news media’s attention of misinformation
Segmenting Consumer Location-Product Preferences for Assortment Localization
No full textWhen managing multiple stores within the same marketplace, retailers must tailor product assortments to reflect the heterogeneous preferences of local communities. This paper introduces
a consumer-centric, data-driven framework for interpretable market structure discovery and supporting localized assortment planning. At the core of the framework is the dual Poisson Dynamic System with Multilayer Factorization (dPDS-MF), which integrates a probabilistic generative model with a tensor factorization architecture to estimate spatiotemporal supply and demand patterns across products and locations. Specifically, dPDS-MF can profile different consumer segments driven by store visiting preferences, measure relationships between store locations, and simultaneously estimate each segment’s product preferences. These model outputs are then used to formulate a choice process for the localized assortment optimization problem. We apply our proposed framework to the retail vending market in major train stations in Japan. We demonstrate the face validity of the model outputs for guiding the selections of products at each location. We also show that the localized assortments generated by our framework are more meaningful and practical than benchmark strategies in the literature. Beyond the core model, we introduce several methodological extensions, highlighting the flexibility of the framework in addressing real-world retail scenarios and laying a foundation for future research
Practical Lightweight Security: Physical Unclonable Functions and the Internet of Things
No full textIn this work, we examine whether Physical Unclonable Functions (PUFs) can act as lightweight security mechanisms for practical applications in the context of the Internet of Things (IoT). In order to do so, we first discuss what PUFs are, and note that memory-based PUFs seem to fit the best to the framework of the IoT. Then, we consider a number of relevant memory-based PUF designs and their properties, and evaluate their ability to provide security in nominal and adverse conditions. Finally, we present and assess a number of practical PUF-based security protocols for IoT devices and networks, in order to confirm that memory-based PUFs can indeed constitute adequate security mechanisms for the IoT, in a practical and lightweight fashion.
More specifically, we first consider what may constitute a PUF, and we redefine PUFs as inanimate physical objects whose characteristics can be exploited in order to obtain a behaviour similar to a highly distinguishable (i.e., “(quite) unique”) mathematical function. We note that PUFs share many characteristics with biometrics, with the main difference being that PUFs are based on the characteristics of inanimate objects, while biometrics are based on the characteristics of humans and other living creatures. We also note that it cannot really be proven that PUFs are unique per instance, but they should be considered to be so, insofar as (human) biometrics are also considered to be unique per instance.
We, then, proceed to discuss the role of PUFs as security mechanisms for the IoT, and we determine that memory-based PUFs are particularly suited for this function. We observe that the IoT nowadays consists of heterogeneous devices connected over diverse networks, which include both high-end and resource-constrained devices. Therefore, it is essential that a security solution for the IoT is not only effective, but also highly scalable, flexible, lightweight, and cost-efficient, in order to be considered as practical. To this end, we note that PUFs have been proposed as security mechanisms for the IoT in the related work, but the practicality of the relevant security mechanisms has not been sufficiently studied.
We, therefore, examine a number of memory-based PUFs that are implemented using Commercial Off-The-Shelf (COTS) components, and assess their potential to serve as acceptable security mechanisms in the context of the IoT, not only in terms of effectiveness and cost, but also under both nominal and adverse conditions, such as ambient temperature and supply voltage variations, as well as in the presence of (ionising) radiation. In this way, we can determine whether memory-based PUFs are truly suitable to be used in the various application areas of the IoT, which may even involve particularly adverse environments, e.g., in IoT applications involving space modules and operations.
Finally, we also explore the potential of memory-based PUFs to serve as adequate security mechanisms for the IoT in practice, by presenting and analysing a number of cryptographic protocols based on these PUFs. In particular, we study how memory-based PUFs can be used for key generation, as well as device identification, and authentication, their role as security mechanisms for current and next-generation IoT devices and networks, and their potential for applications in the space segment of the IoT and in other adverse environments. Additionally, this work also discusses how memory-based PUFs can be utilised for the implementation of lightweight reconfigurable PUFs that allow for advanced security applications. In this way, we are able to confirm that memory-based PUFs can indeed provide flexible, scalable, and efficient security solutions for the IoT, in a practical, lightweight, and inexpensive manner
People systematically overlook subtractive changes (2021): Replication and extension
No full textPeople systematically overlook subtractive changes and favor additive ones when generating new ideas. In a preregistered experiment conducted via the Prolific platform among French adults (N = 477), we replicated Experiments 2, 3 and 4 in Adams and colleagues (2021)’s study. We replicated the overlooking of subtraction, as participants generated 1155 additive ideas and only 297 subtractive ideas. Cueing participants (“Remember that you can add things or take them away”) increased the percentage who generated at least one subtractive idea (overall OR = 2.52, improvement condition, ϕ = 0.18, make-it-worse condition, ϕ = 0.24).
Results therefore provided empirical support for the overlooking of subtractive changes hypothesis. We also found that norms affected the generation of new ideas (descriptive OR = 7.49, injunctive OR = 6.86). Cues and injunctive (but not descriptive) norms were both related to the asymmetry
Cinquenta anos de memória operacional: Teorias atualizadas e direções futuras
No full textWorking memory has been one of the most important topics in cognitive psychology since the classic chapter published by Baddeley and Hitch (1974) 50 years ago. In this article, we present three influential theoretical models in the literature since then: the multicomponent model, the time-based resource sharing (TBRS) model, and the embedded-processes model. We explain the development of these theories and summarize their characteristics regarding the structure and functioning of working memory. A comparative framework between the three theories is proposed, along with considerations on the theoretical advancement in the field and directions for future research
Unveiling Strategic Governance and User Dynamics in Weibo's Community-driven Content Moderation System
No full textSocial media companies continuously experiment with various platform governance models to tackle content moderation challenges, which calls for a comprehensive and empirical understanding of how a content moderation system evolves over the long term. Our study aims to fill this gap through a quantitative and qualitative study of Weibo's community-driven content moderation system, leveraging eleven million public moderation cases and decision data from 2012 to 2021. Based on reporting activities, platform decisions, and jury actions, we investigated the motivations and behavior patterns of three important actors in this governance model: reporting users, the platform, and user jurors. We suggest that users who frequently reported content and initiated the community-driven content moderation process tend to exhibit patterns of voluntarily policing the community or abusing others, sometimes coordinately, and were also treated differently by the platform. We indicate that Weibo's strategic moderation decisions have significantly distinctive preferences over cases from various topic categories and different levels of harmfulness, and the cases involving socially sensitive issues were given more consideration and penalized more severely than common misbehaviors. We also explore how the platform leveraged the usually one-sided votes of digital jurors to endorse its final decisions and find that the reason notes given by crowdsourced jurors also revealed a serious issue of decaying motivation. Our findings offer important insights into the coordination between a social media platform and its volunteer moderators to moderate an online community and address the question of how an autonomic platform governance model can prevail or perish