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Symphony:John Wallace
No full textThis recording features John Wallace’s creation – Symphony. The composition of the title work began in 1974, and was only completed in 2024, some fifty years later. Written for brass band, brass quintet, double-belled solo trumpet, six natural trumpets, live electronics, organ, and bodhrán, this recording welcomes the eclectic contributions from Kingdom Brass, Whitburn Band, The cooperation band, The Wallace Collection, Sandy McGrattan and the RCS natural trumpet consort, Marco Blaauw (double-belled trumpet), Anthony George (tuba), Alistair McDonald (live electronics), David Hamilton (organ) and Steve Foreman (bodhrán), with Kingdom Brass also featuring in the closing track of the Martin Luther King-inspired Where do we go from here? Credits:John Wallace | The Wallace Collection | Whitburn Band | Kingdom Brass | The cooperation band | Sandy McGrattan | Royal Conservatoire of Scotland natural trumpet consort | David Hamilton (organ) | Steve Foreman (bodhrán) | Marco Blaauw (double-belled trumpet) | Alistair MacDonald (live electronics) | Anthony George (Tuba) | Bede Williams (conductor
Stabilizing open photon condensates by ghost-attractor dynamics
No full textWe study the temporal, driven-dissipative dynamics of open photon Bose-Einstein condensates (BEC) in a dye-filled microcavity, taking the condensate amplitude and the noncondensed fluctuations into account on the same footing by means of a cumulant expansion within the Lindblad formalism. The fluctuations fundamentally alter the dynamics in that the BEC always dephases to zero for a sufficiently long time. However, a ghost attractor, although outside of the physically accessible configuration space, attracts the dynamics and leads to a plateaulike stabilization of the BEC for an exponentially long time, consistent with experiments. We also show that the photon BEC and the lasing state are separated by a true phase transition, since they are characterized by different fixed points. The ghost-attractor nonequilibrium stabilization mechanism is an alternative to prethermalization and may possibly be realized on other dynamical platforms as well
Introduction:Sea of islands and poetics of relation: rethinking islandness
No full textIntroduction also published in French and Spanis
Directly observing replica symmetry breaking in a vector quantum-optical spin glass
No full textSpin glasses are quintessential examples of complex matter. Although their ordering lacks complete theoretical understanding, abstract models of spin glasses inform problems in other fields, such as combinatorial optimization and artificial intelligence—where they form a mathematical basis for neural network computing. We demonstrate the ability to realize a spin glass of a distinct driven-dissipative and vector form. By microscopically visualizing its glassy spin states, the technique allows us to directly measure replica symmetry breaking and the resulting ultrametric hierarchical structure. Ultrametricity is known to be emergent in models of evolution, protein folding, and climate change; this work shows it to be directly observable in a physically realized system
Old age variably impacts chimpanzee engagement and efficiency in stone tool use
No full textWe know vanishingly little about how long-lived apes experience senescence in the wild, particularly with respect to their foraging behaviors. Chimpanzees use tools during foraging, and given the cognitive and physical challenges presented by tool use, tool-use behaviors are potentially at a heightened risk of senescence, though this has never been investigated in wild individuals. Accordingly, we sampled data from a longitudinal video archive that contained footage of wild chimpanzees using stone hammers and anvils to crack hard-shelled nuts (nut cracking) at an ‘outdoor laboratory’ over a 17-year period (with focal chimpanzees aging from approximately 39–44 to 56–61 years across this period). Over time, elderly chimpanzees began attending experimental nut-cracking sites less frequently than younger individuals. Several elderly chimpanzees exhibited reductions in efficiency across multiple stages of nut cracking, including taking longer to both select stone tools prior to use and use tools to crack open nuts and consume the associated pieces of kernel. Two chimpanzees began using less streamlined behavioral sequences to crack nuts, including a greater number of actions (such as more numerous hammer strikes). Notably, we report interindividual variability in the extent to which elderly chimpanzees’ tool-use behaviors changed during our sample period – ranging from small to profound reductions in engagement and efficiency – as well as differences in the specific aspects of nut cracking that changed for each individual. We discuss the possible causes of these changes – and recommendations for future research – with reference to literature surrounding the senescence of captive and wild primates
Imagined war
No full textHow war was imagined before the outbreak of conflict in 1914 has been an ongoing source of interest to historians. Ideas about future war have been explored as a potential explanation for the willingness of societies to go to war and in terms of ‘war enthusiasm’. They have also underpinned a perception that military-political elites believed in a ‘short war illusion’ that encouraged them to risk conflict. In both cases recent historiography has overturned these long-standing myths, opening the way for a more creative approach of using ‘imagination’ as a means of re-examining the First World War
Corotating interaction regions (CIRs):impacts with exoplanets
No full textCorotating interaction regions (CIRs) are compressions that form in stellar winds when streams of different speeds collide. They form an Archimedean spiral around the star and can compress any exoplanetary magnetospheres they impact. They may also steepen into shocks capable of accelerating particles to high energies. We model the frequency and strength of these CIRs for stars of spectral types F-M. We show that the minimum radius, rCIR = Δφuslow/Ω, at which CIRs form varies strongly with the rotation rate (and hence age) of the star. For some exoplanets, such as those in Earth or Mars orbits, CIRs can form within the exoplanet’s orbit at all stellar rotation rates, depending on the angular size of the fast wind segment (Δφ). These exoplanets will experience CIR impacts at all stellar ages. However, for closer-in orbits such as Mercury or Venus, this may only be the case at higher stellar rotation rates. Both the frequency and impact of CIRs depend on the stellar rotation rate. For exoplanets with Porbit ≫ P∗, CIR impacts lasting for a time Δt raise the exoplanetary outflow rate by a factor R. If P∗ ≤ NΔt the CIR pulses overlap in time, whereas if NΔt < P∗ ≤ NΔt(R + 1), the planet experiences discrete pulses of compression and relaxation and the CIR-related outflow is more than 50 per cent of the total. For P∗ > NΔt(R + 1) the pulses are less frequent, and contribute less than 50 per cent of the total outflow
Renewable solvents for Diels–Alder/cheletropic reaction sequences:preparation of pentaphenylbenzene and 1,2,4-triphenyltriphenylene
No full textPolycyclic aromatic compounds can often be made by a sequence featuring an initial Diels–Alder [4 + 2] cycloaddition reaction, followed by cheletropic extrusion of carbon monoxide. These reactions normally require heating the diene and dieneophile in petrochemical-derived aromatic hydrocarbon solvents, such as xylenes or diphenyl ether. This article summarizes the results of attempts to use renewable solvents in place of those currently in use to prepare pentaphenylbenzene and 1,2,4-triphenyltriphenylene. Dihydrolevoglucosenone, p-cymene, ethyl lactate, diethyl carbonate, and cyclopentyl methyl ether have all been successfully evaluated as renewable solvent alternatives in Diels–Alder/cheletropic reaction sequences. An analysis of the products from the reactions investigated did not show evidence of oxidative degradation of the diene reactants. Furthermore, norbornadien-7-one intermediates were not isolated from any of the reactions tested
