Turbulence–chemistry interaction in a Mach-7 hypersonic boundary layer with significant production of radical species is characterised using direct numerical simulation. Overriding a non-catalytic surface maintained as isothermal at 3000 K, the boundary layer is subject to finite-rate chemical effects, comprising both dissociation/recombination processes as well as the production of nitric oxide as mediated by the Zel’dovich mechanism. With kinetic-energy dissipation giving rise to temperatures exceeding 5300 K, molecular oxygen is almost entirely depleted within the aerodynamic heating layer, producing significant densities of atomic oxygen and nitric oxide. Owing to the coupling between turbulence-induced thermodynamic fluctuations and the chemical-kinetic processes, the Reynolds-averaged production rates ultimately depart significantly from their mean-field approximations. To better characterise this turbulence–chemistry interaction, which arises primarily from the exchange reactions in the Zel’dovich mechanism, a decomposition for the mean distortion of finite-rate chemical processes with respect to thermodynamic fluctuations is presented. Both thermal and partial-density fluctuations, as well as the impact of their statistical co-moments, are shown to contribute significantly to the net chemical production rate of each species. Dissociation/recombination processes are confirmed to be primarily affected by temperature fluctuations alone, which yield an augmentation of the molecular dissociation rates and reduction of the recombination layer’s off-wall extent. While the effect of pressure perturbations proves largely negligible for the mean chemical production rates, fluctuations in the species mass fractions are shown to be the primary source of turbulence–chemistry interaction for the second Zel’dovich reaction, significantly modulating the production of all major species apart from molecular nitrogen.

Animals routinely suffer violence by humans, especially during war, but it is unclear how much people in conflict environments express concern for animal welfare. Based on a 2,008-person survey in Ukraine in May 2024, we find that respondents are anthropocentric, prioritizing human over animal suffering; biocentric, regarding both as important; or, in a small minority, zoocentric, emphasizing animal over human suffering. Experimental priming on violence against animals during the Russia–Ukraine war has limited effect on changing attitudes toward animal welfare, but it does increase resource allocation to animal relief organizations. A war crimes punishment experiment also shows that while respondents sanction perpetrators of human suffering more severely than perpetrators of animal suffering, violence against animals is still strongly penalized, indicating appreciation for animal rights, justice, and accountability. We reflect on the implications of our findings for speciesist versus posthumanist understandings of suffering during war.

This paper reports on a web-based experiment to investigate the perception of prominence in words with different focus structures in Italian. In the experiment, native listeners of the Bari variety of Italian, and German learners of Italian, rated the perceived prominence of object nouns in broad and narrow focus and post-focally using a visual analogue scale. Although both groups of listeners rated words in narrow focus as higher in prominence than words in broad focus, there were differences between the two groups in rating post-focal words. While German learners rated post-focal words as less prominent than those in broad focus, native Italian listeners perceived words in both of these conditions as equally prominent. The Italian ratings are particularly striking, as post-focal words had flat pitch and were weaker in terms of periodic energy mass than words in broad focus, leading to the conclusion that the native listeners were rating the words by taking their knowledge of the prosodic system of Italian into account. Our results confirm phonological accounts of Italian as having post-focal accents, even when the pitch is flat.

Cette étude propose une relecture inédite de la physique élémentaire d’Averroès à partir de trois questions laissées ouvertes par les textes d’Aristote : le statut des qualités premières, l’existence d’une intensité maximale de ces qualités, et la possibilité pour les corps simples d’exister à l’état pur. En croisant les commentaires au De caelo, au De generatione et corruptione et aux Meteorologica, son apport majeur consiste à faire apparaître, dans un corpus souvent lu à travers le seul prisme péripatéticien, l’influence structurante de Galien. En articulant les schèmes hylémorphiques d’Alexandre d’Aphrodise avec la théorie galénique des puissances naturelles, Averroès élabore une théorie du sensible inédite, critique à l’égard d’Avicenne, selon laquelle le cosmos est un système dynamique clos, dans lequel le mélange perpétuel, orchestré par le mouvement céleste, donne lieu à ce que l’on peut appeler une complexion cosmique : non pas un équilibre absolu, mais une somme réglée de complexions relatives, à la mesure de la diversité du sensible.

This study investigates the phonetic structures of Lushootseed obstruents from archival recordings dating to the 1950s, and seeks to address the following questions: (i) Which acoustic dimensions characterize the stop, affricate, and fricative contrast in Lushootseed? (ii) which acoustic dimensions characterize ejective types in Lushootseed? and (iii) which methods can be used to characterize acoustic properties of Lushootseed obstruents from old archival recordings? Several acoustic measures were used on two elder speakers. These measurements include: Voice Onset Timing (VOT); closure duration; burst intensity for stops; dynamic measures of intensity for affricates; voice onset quality measures for stops and affricates, which include f0 perturbation, jitter perturbation, and amplitude characteristics of the following vowel; and spectral measurements for affricates and fricatives, which includes the frequency of the main peak at the low- and mid-frequency ranges (FreqM) and DCT coefficients. The findings reveal that several of these acoustic measures characterize the stop, affricate, and fricative contrast in Lushootseed.

Psychotherapy chatbots have attained remarkable fluency, skill and ubiquity – having become the single most frequent reason people use artificial intelligence. Their uncanny ability to engage and validate is a two-edged sword – useful for the majority of users who are experiencing problems of everyday life or have milder mental disorders, but dangerous for the minority who have more severe problems (e.g. psychosis, bipolar disorder, self-mutilation, suicide, antisocial impulses, eating disorders, conspiracy theories, religious and political extremism). Chatbots are created to make money, without meaningful quality control, safety guardrails and external regulation. They will likely be misused to create addiction, reduce human contact, invade privacy, allow exploitation and create opportunities for marketing and political propaganda. Chatbots also make mistakes (’hallucinations’), deceptively cover them up and sometimes go rogue (acting outside the parameters set by their human programmers). Psychotherapy practitioners and associations are curiously complacent about the rapid emergence of artificial intelligence competition. Their passivity reflects ignorance about the power of chatbots, denial of their likely impact and arrogance regarding their capacities (e.g. ‘no machine will ever replace me’). This is both incorrect and foolhardy – human therapists expect to win in competition for most healthier patients and must train or retrain to do things artificial intelligence does poorly – working with the more seriously ill and in settings and situations that are more idiosyncratic, chaotic or quickly changing. If we can’t work with artificial intelligence, we are likely to be replaced by it. I will describe: (a) benefits of chatbot therapy, (b) its terrifying dangers, (c) its likely impact on human therapy and training and 4) ways we can adapt to the artificial intelligence threat.

Let $\Sigma$ be an alphabet and $\mu$ be a distribution on $\Sigma ^k$ for some $k \geqslant 2$. Let $\alpha \gt 0$ be the minimum probability of a tuple in the support of $\mu$ (denoted $\mathsf{supp}(\mu )$). We treat the parameters $\Sigma , k, \mu , \alpha$ as fixed and constant. We say that the distribution $\mu$ has a linear embedding if there exist an Abelian group $G$ (with the identity element $0_G$) and mappings $\sigma _i : \Sigma \rightarrow G$, $1 \leqslant i \leqslant k$, such that at least one of the mappings is non-constant and for every $(a_1, a_2, \ldots , a_k)\in \mathsf{supp}(\mu )$, $\sum _{i=1}^k \sigma _i(a_i) = 0_G$. In [Bhangale-Khot-Minzer, STOC 2022], the authors asked the following analytical question. Let $f_i: \Sigma ^n\rightarrow [\!-1,1]$ be bounded functions, such that at least one of the functions $f_i$ essentially has degree at least $d$, meaning that the Fourier mass of $f_i$ on terms of degree less than $d$ is at most $\delta$. If $\mu$ has no linear embedding (over any Abelian group), then is it necessarily the case that

\begin{equation*}\left | \mathop {\mathbb{E}}_{({\textbf {x}}_1, {\textbf {x}}_2, \ldots , {\textbf {x}}_k)\sim \mu ^{\otimes n}}[f_1({\textbf {x}}_1)f_2({\textbf {x}}_2)\cdots f_k({\textbf {x}}_k)] \right | = o_{d, \delta }(1),\end{equation*}

$\to 0$

$d \to \infty$

$\delta \to 0$

In this paper, we answer this analytical question fully and in the affirmative for $k=3$. We also show the following two applications of the result.

1. 1. The first application is related to hardness of approximation. Using the reduction from [5], we show that for every $3$-ary predicate $P:\Sigma ^3 \to \{0,1\}$ such that $P$ has no linear embedding, an SDP (semi-definite programming) integrality gap instance of a $P$-Constraint Satisfaction Problem (CSP) instance with gap $(1,s)$ can be translated into a dictatorship test with completeness $1$ and soundness $s+o(1)$, under certain additional conditions on the instance.

2. 2. The second application is related to additive combinatorics. We show that if the distribution $\mu$ on $\Sigma ^3$ has no linear embedding, marginals of $\mu$ are uniform on $\Sigma$, and $(a,a,a)\in \texttt{supp}(\mu )$ for every $a\in \Sigma$, then every large enough subset of $\Sigma ^n$ contains a triple $({\textbf {x}}_1, {\textbf {x}}_2,{\textbf {x}}_3)$ from $\mu ^{\otimes n}$ (and in fact a significant density of such triples).

Over the last two decades, Marxism has experienced a significant revival, including in the discipline of law. The 2003 Iraq War and, perhaps more obviously, the 2008 financial crisis posed questions about the relationship between law, capitalism and imperialism that mainstream legal scholarship had difficulty answering. One marked exception to this revival has been in the field of European Union (EU) law. EU law scholarship, perhaps understandably given that few Member States participated in the invasion, had little to say about the Iraq War. For its part, the 2008 financial crisis and its manifestation in Europe as the ‘Euro-Crisis’ prompted a ‘critical turn’ in EU legal studies.1 However, these two movements – the Marxist tradition and critical EU law scholarship – have largely failed to meet. Marxist analyses of EU law, let alone the development of a full-blown Marxist theory of EU law, remain almost non-existent.

This article examines historical perceptions of the territorial extent of Bod, the Tibetan toponym for ‘Tibet’. In a bid to establish what area second-millennium authors (and audiences) may have pictured when this toponym was invoked, we analyse instructive passages from five historiographical works, mostly dating from between the twelfth and seventeenth centuries. The rough-hewn maps of Bod ‘Tibet’ that emerge from this procedure differ quite radically from one work to the next, and at times even between different passages from a single source. While one work may see ‘Tibet’ as the territory directly centered on the Tibetan Plateau’s south-central river valleys, another source may forward an image of a ‘Tibet’ that is thrice as large. Works may also allow for shifts in its borders from one political period to the next, or incorporate multiple incongruous territorial descriptions. This material helps answer what ‘Tibet’ meant in different periods and places, and to different people—questions that have only poorly been studied outside of modern political history. One relevant finding, among others, is that the notion of a ‘Tibet’ that covers a large part of the Tibetan Plateau, incorporating for instance sites in contemporary eastern Qinghai, was not in fact a modern innovation.

This article explores the systems of policing that emerged in the early Cape Colony (1652–1830). Contrary to previous historical scholarship that understood the institution to be largely nonexistent or of marginal importance to the colony’s political economic development, this article argues that the Cape colony’s systems of policing, which doubled as ad hoc military organizations, were not so much weak as privatized. It shows how this persistent tendency was motivated by the Dutch East India Company’s desire to maximize profits—though it manifested differently in different parts of the colony. Moreover, this article demonstrates that the mercantile economy that the company installed at the Cape ensured that private policing would become a vehicle of indigenous dispossession. In doing so, it seeks to contribute to the field of African carceral studies and understandings of processes of racialization in the early Cape.

This article is the introduction to the Special Issue on The Constitution of Political Economy. It provides an overview of six articles which in distinctive yet overlapping ways explore three key issues. First, how the economy and the polity are embedded in society. Second, how interdependence shapes institutional arrangements. Third, how different levels of aggregation determine levels of policy-making, notably the importance of intermediate institutions.

We derive the scale-by-scale uncertainty energy budget equation and demonstrate theoretically and computationally the presence of a self-similar equilibrium cascade of decorrelation in an inertial range of scales during the time range of power-law growth of uncertainty in statistically stationary homogeneous turbulence. This cascade is predominantly inverse and driven by compressions of the reference field’s relative deformation tensor and their alignments with the uncertainty velocity field. Three other subdominant cascade mechanisms are also present, two of which are forward and also dominated by compressions and one of which, the weakest and the only nonlinear one of the four, is inverse. The uncertainty production and dissipation scalings which may follow from the self-similar equilibrium cascade of decorrelation lead to power-law growths of the uncertainty integral scale and the average uncertainty energy which are also investigated. Compressions are key not only to chaoticity, as previously shown, but also to stochasticity.