We generalize Hopf’s theorem to thermostats: the total thermostat curvature of a thermostat without conjugate points is non-positive and vanishes only if the thermostat curvature is identically zero. We further show that, if the thermostat curvature is zero, then the flow has no conjugate points and the Green bundles collapse almost everywhere. Given a thermostat without conjugate points, we prove that the Green bundles are transverse everywhere if and only if it is projectively Anosov. Finally, we provide an example showing that Hopf’s rigidity theorem on the $2$-torus cannot be extended to thermostats. It is also the first example of a projectively Anosov thermostat which is not Anosov.

Waste management is one of the major environmental challenges of the twenty-first century. This Perspective examines how vegetation dynamics at composting facilities and landfills both reflect and influence anthropogenic environmental change. We define our use of the Anthropocene as a human-dominated epoch that is functionally and stratigraphically distinct from the Holocene, and we argue that waste-derived ecosystems constitute model systems for detecting its signals through technogenic substrates and synanthropic succession. Although composting reduces pressure on landfills, incomplete processing of biowaste can disseminate propagules of invasive plant species. Landfills, shaped by disturbance and altered edaphic regimes, support synanthropic plant assemblages dominated by neophytes that act as bioindicators of leachate stress and other pressures. At the same time, spontaneous vegetation provides functional benefits, including slope stabilization, organic matter accumulation and habitat provision during early successional stages. We bring together information on risks and functions, link ecological criteria to permitting, monitoring and post-closure management pathways, and outline practical considerations for integrating plant-based indicators with geochemical screening. These steps enable ecologically sensitive strategies to be implemented that mitigate biodiversity risks while leveraging succession to improve the resilience of waste-derived landscapes.

Despite years of efforts to combat disinformation, we remain far from a satisfactory set of solutions. The rise of generative AI, which enables the creation of highly credible fake content at scale, suggests that the problem is likely to grow even more severe. Lessons from the recent pandemic also call for a reconsideration of how disinformation should be addressed. This paper proposes a new approach that focuses not only on regulating everyone who spreads false information, but also on those who hold epistemic power – individuals with the capacity to shape what others know or believe. Such a strategy has the potential to move the debate forward, as it avoids the most common objection to disinformation regulation: the fear of widespread censorship. The paper argues that an individual’s epistemic position can justifiably differentiate their legal duties, and that those who possess epistemic power should bear corresponding legal – specifically, criminal – responsibility for the abuse of that power in spreading disinformation.

In 1940, Serge Koussevitzky officially founded the Berkshire Music Center (later known as Tanglewood) and appointed Aaron Copland as head of the faculty. Copland actively participated in the US cultural diplomatic initiative of the Good Neighbor Policy by setting up the conditions for modern Latin American composers to attend the Center. By examining the contribution of modern Latin American art music, especially at Tanglewood, this article reflects on the relationship between music and politics, and shows that musical modernism encompasses a much broader artistic spectrum than previously thought.

This article discusses the grammatical role played by the interpretation of an action as either intentional or accidental. It focuses on two grammatical restrictions that exhibit sensitivity to such interpretation. The first concerns so-called subject obviation, whereby, in many European languages, the subject of the subjunctive clause cannot refer to the same individual as the subject of the matrix clause. For the purpose of this article, an important property of subject obviation is that it is weakened in the case of accidental actions. The second restriction pertains to an aspectual restriction in negative imperatives and desire statements in Slavic, which disallows the perfective aspect in these constructions. As is the case with subject obviation, the aspectual restriction in Slavic is lifted when the action is interpreted as accidental. This article argues for a unified semantic-pragmatic account of the weakening of subject obviation and aspectual restriction. It also shows that this weakening of obviation and of aspectual restriction is part of a larger picture where the interpretation of an action as intentional versus accidental plays a central role.

The political participation of Black women has important consequences for electoral outcomes in the US, yet little is known about whether and how affect (both negative and positive) influences this group’s engagement in American politics. Despite the prevalent stereotype that Black women are “angry,” scholarly exploration of the effects of the emotions of these women is rare. In this paper, we highlight a gap in theories that center on Black women and argue that survey question wording about affect may impact how Black women express positive or negative emotions in relation to their political behavior. Using 2016 and 2020 CMPS data, we find support for our expectations. This project highlights the importance of group-specific, intersectional theories and the potential limitations to our understanding of how affect influences political participation.

The propagation of high-energy X-rays or hot electrons have the potential to alter the initial conditions in experimental target designs, especially at material interfaces, for laser-driven inertial confinement fusion (ICF) and high-energy density (HED) experimental platforms. Hot-electron preheat can drastically modify the initial conditions of experimental targets used to study the deceleration-stage Rayleigh–Taylor instability (RTI) both with and without applied magnetic fields. Therefore, it is necessary to understand and quantify the impact of hot-electron preheat. The hydrodynamic (HD) capabilities in the Ares code are used to study the effects varying levels of preheat can have on RTI evolution. The experimental and computational studies presented in this work demonstrate that at high laser intensities of around or greater than $10^{15} \,\textrm {W}\, \textrm {cm}^{-2}$, there is hot-electron generation from laser plasma instabilities which induces substantial preheat and impacts the morphology of RTI evolution and even inhibits the intended RTI growth such that it is not observable experimentally. The necessity of better quantifying hot-electron induced preheat and mitigating its impact on such high-intensity direct-drive laser experiments in the future is discussed.

Given historical and contemporary hegemonic discourse that portrays the UnitedStates as a monolingual nation, a critical perspective is needed to counter thissocietal erasure of bi/multilingualism. The present study reports on anintroductory linguistics course about bilingualism in the US that adoptedcritical language awareness as its pedagogical framework. Results from anend-of-semester survey show that students from diverse linguistic backgrounds(monolingual English, heritage language, L2 world language, and L2 Englishspeakers) demonstrated critical awareness about language, albeit with somedifferences that were mediated by their linguistic backgrounds. Implications forlinguistics and world language programs, as well as adaptations for futureiterations of the course, are also discussed.

John Dewey holds that uncertainty is a central feature of the concrete interaction between organism and environment, and he mobilizes this diagnosis to explain both the emergence of inquiry and the persistence of speculative and abstract philosophies. However, we show that material reality is not uncertain and that the quest for certainty cannot explain the flight from the concrete, but should explain a return to it. Drawing on historical, philosophical, and sociological sources (most notably Edgar Zilsel’s thesis and the embodied knowledge of artisans) we invert Dewey’s interpretative framework: epistemic uncertainty arises not from material reality, but from theoretical abstraction. This reinterpretation enables a reformulation of Dewey’s critique of dualism and provides the basis for a pragmatist epistemology grounded in the relative stability of practical experience. Finally, it opens the way for a reconsideration of the foundations of democracy from a non-relativistic perspective.

Adults exhibit different acoustic characteristics in infant-directed speech (IDS) compared to adult-directed speech (ADS). We investigate differences in voice quality between IDS and ADS in sentences read aloud by Hungarian mothers, using longitudinal data gathered at various child ages (4, 8, 18 months). Vowels in IDS are found to be breathier than those in ADS, regardless of the infant’s age. Possible motivations for this difference may include emotional expressions, as breathiness relates to positive emotions, and speech entrainment, since the speech of children is breathier than that of adults.

This article demonstrates how political science, particularly the emerging field of American Political Economy (APE), can more robustly theorize and study the political economy of systemic racism by drawing on insights from critical race theories, including intersectionality and racial capitalism, and post/anti-colonial theory. A paired case study of the foreclosure “noncrisis” of the 1990s and the coerced sterilization of incarcerated women in California during the early 2000s highlights three key contributions of critical race theories: (1) intersectionality reveals nonuniformity, unintended consequences of purportedly progressive policy, and underscores the importance of margins-to-center resistance; (2) feudal-colonial roots illuminate how racialized hierarchies become institutionalized in law and policy, often without explicit racial language; and (3) racial capitalist logics explain how administrative tools, such as risk assessment and cost-benefit analysis, reproduce racial hierarchy through markets. This framework offers APE a more historically grounded, power-conscious, and theoretically expansive approach to systemic racism and underscores the urgency of resisting efforts to suppress such scholarship.

The division of cognitive labor leads to what Barry has recently called epistemic alienation: a problematic separation of individuals from epistemic goods. According to Barry, individuals are alienated from epistemic virtues because an efficient division of cognitive labor requires them to manifest a lack of virtues. I argue that this is a mistaken diagnosis of the source of epistemic alienation. Participating in high-functioning collectives does not prevent individuals from being robustly virtuous; rather, our cognitive limitations make it impossible for us to live up to the highest standards of epistemic conduct. Collectives transcend these cognitive limitations to achieve what individuals cannot by harnessing those same limitations in their members. Furthermore, I argue that we should distinguish the epistemic weaknesses that facilitate the division of cognitive labor from those that result from the division of labor. Only the latter are aspects of epistemic alienation. By dividing our cognitive labor over larger populations of agents and artifacts, we have massively accelerated our rate of epistemic productivity but have thereby created conditions that are variously inhospitable for the thinking of individuals by alienating them from the products, processes, and environments of inquiry. These forms of separation are problematic insofar as they amplify intellectual vices, incapacitate reason, and induce cognitive biases.

We are self-conscious creatures thrown into a world, which is not of our making. What is the connection between being self-conscious and being related to an objective world? The Practical Self argues that self-consciousness requires faith in ourselves as the agents of our thinking and that this faith is sustained by a set of practices which relate us to a world of others.