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Chiral molecular 4f qubits by post functionalization
No full textWe herein demonstrate the synthesis of a pair of enantiomerically pure YbIII complexes by post-functionalisation of the parent YbIII complex via condensation with an enantiomerically pure chiral amine. The enantiomeric pair is structurally characterised by single crystal and powder X-ray diffraction, showing that it crystalises in the P212121 Sohncke space group with Flack parameters close to zero, which confirms their enantiopurity. Circular Dichroism (CD) and absorption spectroscopies in the NIR reveal sharp 27/2 → 25/2 f–f transitions, with gabs values up to 0.07, indicating a chiral environment for the ytterbium centre. Furthermore, a dynamic mechanism with mixing of ligand states is shown to contribute to the CD intensity. X-band pulse Electron Paramagnetic Resonance spectroscopy, on a magnetically dilute single crystal containing 1% of YbIII complexes within the isostructural YIII diamagnetic host, reveals a phase memory time, Tm, of the electronic spin of 600 ns and that it can be coherently manipulated by microwave pulses, as evidenced by Rabi nutations
Extreme terrestrial heat in 2024
No full text2024 shattered temperature records, surpassing 2023’s historic highs to become the warmest year ever recorded. Extreme heatwaves hit West Africa in February, South America and Eastern Europe in March, Southeast Asia in April, and Mexico in June
Phase diagram of CeRh<sub>2</sub>As<sub>2</sub> for out-of-plane magnetic field
No full textThe heavy-fermion superconductor (SC) CeRh2As2 (c = 0.35 K) shows two SC phases SC1 and SC2 when a magnetic field is applied parallel to the axis of the tetragonal unit cell. All experiments to date have indicated that the change in SC order parameter detected at 0* ≈ 4T is due to strong Rashba spin-orbit coupling at the Ce sites caused by the locally noncentrosymmetric environments of the otherwise globally centrosymmetric crystalline structure. Another phase (phase I) exists in this material below 0 = 0.54 K. In a previous specific heat study [K. Semeniuk et al., Phys. Rev. B 107, L220504 (2023)], we have shown that phase I persists up to a field 00 ≈ 6T, larger than *. From thermodynamic arguments, we expected the phase-I boundary line to cross phase SC2 at a tetracritical point. However, we could not find any signature of the phase-I line inside the SC2 phase and speculated that this was because the 0() line is almost perpendicular to the axis and therefore invisible to -dependent measurements. This would imply a weak competition between the two order parameters. Here, we report magnetic-field-dependent measurements of the magnetostriction and ac susceptibility on high-quality single crystals. We see clear evidence of the singularity at 0 inside the SC2 phase and confirm our previous prediction. Furthermore, we observe the transition across the *() line in -dependent specific heat measurements, which show that the *() line is not perpendicular to the field axis but has a positive slope. Our findings support recent muon spin resonance results which suggest coexistence of phase I with SC
Review of Hilary J. Grainger, <i>Designs on Death: The Architecture of Scottish Crematoria</i>
No full textHilary J. Grainger, Designs on Death: The Architecture of Scottish Crematoria (Edinburgh: John Donald, 2020), 338 pp. incl. 241 colour and 28 b&w ills, ISBN 9781910900307, £50 (hardback
Linguistic analysis and psychical research 1940-1960:the case of Casimir Lewy
No full textThis paper explores a hitherto overlooked chapter in the history of analytic philosophy, namely the role that psychical research (i.e. the study of phenomena like telepathy, clairvoyance, ghosts, or communication with spirits of the dead) played in British philosophy between 1940 and 1960. This paper focuses on Casimir Lewy’s (1919–1991) engagement with psychical research and demonstrates that Lewy’s early work constitutes a move towards sustained application of the linguistic method to psychical research between 1940 and 1960. I argue that paying attention to psychical research during this period is significant for two reasons. The first is that this period represents a unique chapter in the history of the analytic tradition, namely, a philosophical preoccupation with the meaning of the language used by psychical researchers. The second is that a foundational moment in the history of analytic philosophy of religion is inseparable from its origin in psychical research
Annie Ernaux abroad:the reception of her 'universal' writings
No full textL’œuvre d’Annie Ernaux est souvent qualifiée d’universelle, bien qu’elle touche à des expériences personnelles et ancrées dans le contexte historique et géographique précis qu’est la France d’après-guerre. La diffusion de son œuvre à l’international, en français et en traduction, ainsi que la reconnaissance mondiale apportée par l’attribution du prix Nobel de littérature, confirment la portée de son écriture et des questions qu’elle aborde, dont la place des femmes dans la société et la mobilité sociale. Cet article évalue l’évolution de la diffusion et de la réception de son œuvre dans une perspective transnationale, en apportant un éclairage particulier sur l’après-Nobel et sur la pertinence du terme « transfuge » à l’international. Il analyse également dans quelle mesure son œuvre peut être génératrice de prises de parole et de récits en-dehors des frontières de la France.Annie Ernaux’s works have often been called universal, in spite of depicting personal experiences steeped in the precise historical and geographical context that is post-war France. The fact that her work is widely disseminated internationally, in French and in translation, and that she was awarded the globally acclaimed Nobel Prize in literature, confirms the broad reach of her writing and the themes she tackles, including women’s place in society and social mobility. This article adopts a transnational perspective to evaluate the circulation and reception of her works, by shedding light on the aftermath of the Nobel Prize and on the pertinence of the notion of “transfuge” (class defector of class migrant) internationally. Finally, it considers Ernaux’s writing as being able to generate other works and discourse beyond the French context.<br/
What images don't show:Distance and filiation in Ernaux-Briot and Ernaux's 'The Super-8 Years' (2022)
No full textThis article examines the careful composition underlying David Ernaux-Briot’s film The Super-8 Years (2022) and its resulting effects. Made from family archives and from a piece written by Annie Ernaux for the occasion, the film goes beyond the conventions of the family movie by giving us access to what images do not (fully) show. Firstly, The Super-8 Years combines a desire of family transmission with the broader impetus to act as sociological commentary. Secondly, through thematic and structural techniques, the composition of the film and that of Annie Ernaux’s text create ruptures which question any possible correlation between image, text and lived experience. Finally, The Super-8 Years sheds light on the notion of authorial figure through a collaborative act of creation, and through its contribution to the narrative and iconography of Ernaux-as-writer
On the importance of reward design in reinforcement learning-based dynamic algorithm configuration:a case study on OneMax with (1+(λ,λ))-GA
No full textDynamic Algorithm Configuration (DAC) has garnered significant attention in recent years, particularly in the prevalence of machine learning and deep learning algorithms. Numerous studies have leveraged the robustness of decision-making in Reinforcement Learning (RL) to address the optimization challenges associated with algorithm configuration. However, making an RL agent work properly is a non-trivial task, especially in reward design, which necessitates a substantial amount of handcrafted knowledge based on domain expertise. In this work, we study the importance of reward design in the context of DAC via a case study on controlling the population size of the (1+(λ,λ))-GA optimizing OneMax. We observed that a poorly designed reward can hinder the RL agent's ability to learn an optimal policy because of a lack of exploration, leading to both scalability and learning divergence issues. To address those challenges, we propose the application of a reward shaping mechanism to facilitate enhanced exploration of the environment by the RL agent. Our work not only demonstrates the ability of RL in dynamically configuring the (1+(λ,λ))-GA, but also confirms the advantages of reward shaping in the scalability of RL agents across various sizes of OneMax problems