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• Speaker: Arrianna Dalla Costa (Warburg Institute)
• Monday 04 March 2024, 13:00-14:00
• Venue: Seminar Room 2, Department of History and Philosophy of Science.
• Series: Cabinet of Natural History; organiser: tjb98.

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• Speaker: David Lowther (University of Durham)
• Monday 26 February 2024, 13:00-14:00
• Venue: Seminar Room 2, Department of History and Philosophy of Science.
• Series: Cabinet of Natural History; organiser: tjb98.

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Christian Gottfried Ehrenberg (1795–1876) researched living and fossil microbes (infusoria) from air, sediment or food samples. His discovery around 1840 that infusoria thriving in the Berlin underground would damage buildings caused an early microbe scare in public. Around 1848, Ehrenberg devoted his attention to ‘blood’ prodigies associated with the cholera, the basis of which he identified as an innocuous red microbe. Both cases allow us to grasp the goals of Ehrenberg’s natural history of microbes: following up on Alexander von Humboldt, he aimed at a full picture of microbes’ place in nature, such as in biological and geological processes, as well as for humans. What is more, understanding the context of his investigations in a time of political instability reveals a dimension of this story beyond historiography of microbiology: Ehrenberg’s conservative-reformist perspective on materialism, religion and the state sheds new light on the relationship of science and politics in Prussia around 1848. Not least, Ehrenberg’s mid-19th century arguments about the omnipresence and impact of microscopic life resonates with contemporary ecological debates about microbes’ effects on geology or the climate.

• Speaker: Mathias Grote (Universität Greifswald)
• Monday 19 February 2024, 13:00-14:00
• Venue: Seminar Room 2, Department of History and Philosophy of Science.
• Series: Cabinet of Natural History; organiser: tjb98.

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In 1617, the prolific Augsburg merchant, art agent, and diplomat Philipp Hainhofer wrote to his longstanding patron, Duke Philipp II of Pomerania-Stettin. He was reporting great news. The duke’s vast and ornately furnished cabinet of curiosities was finally finished after seven years. But now Hainhofer faced the unenviable task of explaining the high costs and lengthy production time. The eloquent, art-loving broker was unerring. He had succeeded in making ‘something princely and prestigious for such an art-savvy and art-loving prince’, to which other princely cabinets were ‘of no comparison’. Covered in cosmic iconography, filled with affective, powerful materials, and housing a distinct pharmaceutical section, the cabinet was intimately linked to the body: the body of its eventual owners; of the artisans who made it; and of the merchant who compiled it.

This paper focuses on the art cabinets produced by Philipp Hainhofer (1578–1647), whose ingenious and rare creations for princely clientele helped foster his reputation as an important cultural broker and diplomat during the first half of the seventeenth century. By examining notions of the macrocosmic and microcosmic universe and the perceived active properties of materials, this paper explores how bodily entanglements with materials influenced decision-making in the space of the cabinet. It argues that Hainhofer’s own experience of corporeal health shaped the ways in which his cabinets came into being, connecting the bodies of geographically, socially and confessionally disparate actors. By directing attention towards health, sensation, and medicine, the material basis of the Pomeranian Cabinet is brought into sharp relief.

• Speaker: Amelia Hutchinson (Faculty of History)
• Monday 12 February 2024, 13:00-14:00
• Venue: Seminar Room 2, Department of History and Philosophy of Science.
• Series: Cabinet of Natural History; organiser: tjb98.

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In recent decades, historians have acknowledged the role that women played in shaping and disseminating scientific knowledge during the Enlightenment. Current scholarship also suggests that fashion was a means through which haptic, economic, and practical knowledge was shared among women. This paper focuses on one particular fashion accessory – the artificial flower – to explore its contribution to our understanding of women’s knowledge of botany in 18th-century France. An analysis of the receipts preserved in the credit records of France’s most famous fashion merchant, Marie-Jeanne [Rose] Bertin (1747–1813), demonstrates high levels of specificity in the flowers that women chose to adorn their outfits. Seventy-five different types of flowers are mentioned using their vernacular names, suggesting that knowledge about a wide variety of flowers was exchanged between fashion merchants and their clients during conversations about clothing. This paper therefore casts the fashion merchant’s shop as a site of botanical knowledge generation and exchange.

• Speaker: Zara Kesterton (Faculty of History)
• Monday 05 February 2024, 13:00-14:00
• Venue: Seminar Room 2, Department of History and Philosophy of Science.
• Series: Cabinet of Natural History; organiser: tjb98.

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In recent decades ‘re-enactment’ has become an accepted, even fashionable, mode of historical work. Building on the talk he gave in the Cabinet of Natural History series last year, Hasok Chang will consider different purposes that are served by different types of historical experiments (historical replication, physical replication, and extension). And then he will discuss his own line of work, which he calls ‘complementary experiments’, which seeks to recover lost scientific knowledge from the past and further extend what has been recovered. The discussion will be illustrated with cases from his current work on the history of ‘battery science’ in the 19th century. He will invite reflections from the audience on the functions of historical experiments for history of science, for science education, and for citizen science. (If there is demand, a follow-up hands-on workshop may be organised in the Easter Term.)

• Speaker: Hasok Chang (Department of History and Philosophy of Science)
• Wednesday 31 January 2024, 13:00-14:00
• Venue: Seminar Room 2, Department of History and Philosophy of Science.
• Series: Cabinet of Natural History; organiser: tjb98.

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R.A. Fisher’s The Genetical Theory of Natural Selection, first published by Oxford’s Clarendon Press in 1930, has a mixed legacy. Its opening chapters, analysing various evolutionary scenarios from a combined Darwinian-Mendelian perspective, are widely celebrated today for their role in laying the theoretical foundations of the so-called ‘modern synthesis’. Its closing chapters, meanwhile, are notorious. Across more than one hundred pages, Fisher provides an extended meditation on eugenics, in which he attempts to explain the collapse of ‘great’ civilisations, past and present, in terms of the overzealous breeding of the ‘undesirable’ lower classes. In this talk I will examine how such a book of ‘two halves’ came to be. Drawing upon previously unstudied archival evidence, I will reconstruct the authorship of this now classic scientific text, overturning long-held ideas about the timing and order of the book’s composition. Doing so not only reveals new insights about the writing and reading of evolutionary science between the Wars; it also recasts a decades-long scholarly dispute regarding the relationship between Fisher’s eugenical commitments and his scientific contributions, at a moment when his legacies are being actively debated once more.

• Speaker: Alex Aylward (University of Oxford)
• Monday 29 January 2024, 13:00-14:00
• Venue: Seminar Room 2, Department of History and Philosophy of Science.
• Series: Cabinet of Natural History; organiser: tjb98.

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In 1637, the French philosopher Pierre Gassendi (1592–1655) sought to console Galileo Galilei, who had recently lost sight in one eye, by proposing an unconventional idea: that distinct visual perception arises solely from the retinal image of a single eye. Between the 1630s and 1650s, Gassendi drew upon Epicurus’s theory of matter to erect a natural philosophical framework that explained sensorial qualities only in terms of atoms and the void. This presentation delves into Gassendi’s account of the causes of our perception of two visual qualities, magnitude and distance, as affected by monocular vision. I examine two of his propositions: first, that the left and right eyes possess dissimilar powers in the apprehension of visual species; and second, contrary to conventional knowledge, that the visual axes of both eyes run parallel through the visual field rather than converging at a focal point.

By analysing Gassendi’s correspondence with Galileo Galilei and Fortunio Liceti, along with the portrayal of visual qualities that the French philosopher delivered in his later works, this talk explores the humanistic foundations of these stances on monocular vision and explains their significance towards validating visual perception in the seventeenth century, amidst the epistemological challenges resulting from the contemporary astronomical advances and the emergence of Cartesian optics.

• Speaker: Guillermo Willis (Warburg Institute)
• Monday 22 January 2024, 13:00-14:00
• Venue: Seminar Room 2, Department of History and Philosophy of Science.
• Series: Cabinet of Natural History; organiser: tjb98.

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Climate action is often presented by policymakers as an economic issue: what would strong regulation to curb emissions do to our economies, what are the most cost-efficient switches, and so on. Yet many normative questions without easy answers arise about burden-sharing and values. Although economics face limitations when applied to complex, large-scale societal challenges like climate change, I wish to highlight a potentially important role for economic methodology. This is the need for economists to illustrate the desirability of greater climate action through modelling more innovative, optimistic scenarios, where the emphasis is on what could be, rather than where the current policies are leading us. We should not ignore the big challenges ahead or engage in ‘climate dreaming’: dismissing the need for urgent mitigation action now in the hope that technological innovations will come to save us. But what gets too little attention is how fast things can sometimes change and how radically some parameters have already changed in the recent years. While ethical values need to be weighed in participatory debates, climate economics can engage in elucidating what is possible and desirable.

• Speaker: Säde Hormio (University of Helsinki)
• Thursday 15 February 2024, 15:30-17:00
• Venue: Large Lecture Theatre, Department of Plant Sciences, Downing Site.
• Series: Departmental Seminars in History and Philosophy of Science; organiser: Lewis Bremner.

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Is obesity a health problem? While most public health organisations and medical researchers seem to consider the rising obesity rates as a major health crisis, some critics remain unconvinced. They view the pathologisation of body fat as an ideological construct. In this talk (based on joint work with Jonathan Sholl) I aim to defend the current medical models of obesity and the view that obesity is a serious health problem. Moreover, while the critics often see medical models of obesity as an important source of stigma, these models might actually help to combat stigma and to increase empathy.

• Speaker: Andreas De Block (KU Leuven)
• Thursday 01 February 2024, 15:30-17:00
• Venue: Large Lecture Theatre, Department of Plant Sciences, Downing Site.
• Series: Departmental Seminars in History and Philosophy of Science; organiser: Lewis Bremner.

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Artisan industrial workers in late nineteenth and early twentieth-century north India faced radical industrial and technological shifts in their trades. To negotiate these changes, many Muslim artisans in trades such as blacksmithing, carpentry, and tailoring asserted distinctive Islamic traditions for their work and technologies of production. In this talk, I argue that Muslim artisans made claims on pious technical knowledge in a context where industrial authority was increasingly associated with the colonial state and Indian middle classes. I likewise explore the archive of Muslim artisans’ pious technical knowledge, analysing the emergence of new intersections of embodied and textual knowledge of craft within the Indian print economy.

• Speaker: Amanda Lanzillo (Brunel University London)
• Thursday 18 January 2024, 15:30-17:00
• Venue: Large Lecture Theatre, Department of Plant Sciences, Downing Site.
• Series: Departmental Seminars in History and Philosophy of Science; organiser: Lewis Bremner.

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Any new physics (NP) lying at the TeV scale must pass stringent flavor as well as collider bounds. Since the top Yukawa gives the largest quantum correction to the Higgs mass, one well-motivated expectation is TeV-scale NP dominantly coupled to the third family. This setup delivers U(2) flavor symmetries that allow one to start explaining flavor at the TeV scale, while simultaneously improving compatibility with the aforementioned bounds.

In all such models that also seek to address the hierarchy problem or the flavor puzzle, there are unavoidably new particles with sizable couplings to the Higgs. Integrating out these heavy particles generates contributions to SMEFT operators that modify EW precision observables, which are precisely measured on the Z- and W-poles. We therefore have a triad of bounds that all models of this type must pass: flavor, direct collider searches, and EW precision tests.

The SMEFT in the U(2)^5 symmetric limit contains only 124 independent operators. This makes an exhaustive phenomenological study tractable, where one can place bounds on all of these operators from each prong of the triad. I will show that while flavor bounds depend on how U(2) is broken, the U(2) symmetric limit is sufficient for EW and collider parts of the triad, which most strongly constrain the flavor conserving parts of the operators. Additionally, important effects come from resummed RGE , in particular from operators with third-family quarks running strongly into Higgs operators constrained on the Z-pole. Finally, I present projections showing how the FCC -ee Z-pole run will indirectly probe a plethora of operators via their unavoidable RG mixing into Higgs operators.

• Speaker: Benjamin Stefanek (King's Coll. London)
• Friday 09 February 2024, 16:00-17:00
• Venue: MR19 (Potter Room, Pavilion B), CMS.
• Series: HEP phenomenology joint Cavendish-DAMTP seminar; organiser: Nico Gubernari.

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The ability to resolve the dynamic evolution of electrocatalytically induced processes with electrochemical liquid phase electron microscopy (ec-LPEM) is limited by the microcell configuration. Herein, we integrate a free-standing tri-layer graphene as a membrane and electrode material into the electrochemical chip and evaluate its suitability as a substrate electrode at the high cathodic potentials required for the CO2 electroreduction (CO2ER). The three-layer stacked graphene was transferred onto an in-house fabricated single working electrode chip for use with bulk-like reference and counter electrodes in order to facilitate evaluation of its effectiveness. Electrochemical measurements showed that the graphene working electrode exhibited a wider inert cathodic potential range than the conventional glassy carbon electrode, while achieving good charge transfer properties for nanocatalytic redox reactions. Operando scanning electron microscopy studies clearly demonstrate the improvement in the spatial resolution but reveal a synergistic effect of the electron beam and the applied potential that limits the stability time window of the graphene-based electrochemical chip. By optimizing the operating conditions, we have achieved the in-situ monitoring of Cu nanocube degradation at the CO2ER potential of -1.1 V versus RHE. Thus, this improved microcell configuration allows for EM observation of catalytic processes at potentials relevant to real systems.

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Building on the context-tree weighting (CTW) circle of ideas, we introduce a collection of statistical ideas and algorithmic tools for modelling and performing exact inference with both discrete and real-valued time series. For discrete time series, we describe a novel Bayesian framework based on variable-memory Markov chains, called Bayesian Context Trees (BCT). A general prior structure is introduced, and a collection of methodological and algorithmic tools is developed, allowing for efficient, exact Bayesian inference. The proposed approach is then extended to real-valued time series, where it is employed to develop a general hierarchical Bayesian framework for building mixture models based on context trees. Again, effective computational tools are developed, allowing for efficient, exact Bayesian inference. The proposed methods are found to outperform several state-of-the-art techniques on both simulated and real-world data from a wide range of applications. This is joint work with Ioannis Kontoyiannis.

• Speaker: Ioannis Papageorgiou, University of Cambridge
• Wednesday 21 February 2024, 14:00-15:00
• Venue: MR5, CMS Pavilion A.
• Series: Information Theory Seminar; organiser: Prof. Ramji Venkataramanan.

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Light-driven circularly polarized luminescence (CPL) material with the sign inversion character is constructed by incorporating photosensitive negative dichroic dye and an appropriate ratio of the opposite dichroic achiral dye into the cholesteric liquid crystals. The CPL signals invert without helical superstructure change. These results provide valuable avenues for developing stimuli-responsive CPL tools for information security and anticounterfeiting applications.

Stimuli-responsive circularly polarized luminescence (CPL) materials show great promise in applying information encryption and anticounterfeiting. Herein, light-driven CPL sign inversion is achieved by combining a photoresponsive achiral negative dichroic dye (KG) and a static achiral positive dichroic dye (NR) as dopants at the 0.5:0.5 weight ratio into the cholesteric liquid crystal (CLC) host. The side chains of KG undergo trans/cis isomerization after 365 nm UV light irradiation, leading to the dichroism (S F) decrease. The |g lum| value of CLC doping with KG (CLC-KG) weakens from 0.67 to 0.28 in response to the order degree change. Taking advantage of its unique CPL response property, the light-driven CPL sign inversion is achieved (from −0.20/0.14 to 0.02/−0.04) by incorporating NR (0.5:0.5) into the CLC-KG with helical superstructure static. Based on the synergistic use of circular polarization and responsiveness state as cryptographic primitives, the multidimensional information encryption CLC system can be realized.

All QFT Lagrangians are redundant, in the sense that you can locally and invertibly redefine its fields without changing its amplitudes. Much like gauge redundancy in gauge theory, field redefinitions mix physics between different Feynman graphs, and induce large cancellations between graphs, making amplitudes difficult to calculate.

I will describe a compact functional formulation to describe the effects of field redefinitions and show how it can generate new off-shell recursion relations for amplitudes, based on arXiv:2202.06965 and arXiv:2312.06748. I will speculate how an improved understanding of transformations under field redefinitions could help calculate phenomenologically useful amplitudes more efficiently.

• Speaker: David Sutherland (University of Glasgow)
• Friday 23 February 2024, 16:00-17:00
• Venue: MR19 (Potter Room, Pavilion B), CMS.
• Series: HEP phenomenology joint Cavendish-DAMTP seminar; organiser: Terry Generet.

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