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Distribution of Holonomy about Closed Geodesics on Compact Hyperbolic 3-Manifolds
Get PDFAn important feature of compact hyperbolic 3-manifolds is their closed geodesics, which have both geometric and dynamical implications. These geodesics are parametrized by their length and holonomy, which describes the angle of rotation by parallel transport about the geodesic. First, we prove ambient prime geodesic theorems, which provide an asymptotic count of closed geodesics by their length and holonomy and imply e ective equidistribution of holonomy in shrinking intervals. These theorems result from a non-spherical Selberg\u27s trace formula which relates spectral information to lengths and holonomies of closed geodesics. Then, we show that although holonomy is equidistributed, there is typically a bias in the finer distribution. In particular, we show that a smoothed bias count is distributed according to a probability distribution and compute the average value, which is typically negative but depends on the number of spectral parameters equal to zero. When all distinct non-zero spectral parameters are linearly independent over the rationals, we explicate the probability distribution function for this sum. In addition, we construct an example where the linear independence hypothesis is not met
Mirabile Dictu: Newsletter of the Bryn Mawr College Libraries
Get PDFhttps://repository.brynmawr.edu/mirabile/1028/thumbnail.jp
Changing paradigms in understanding Chinese imperial law
Get PDFThis essay evaluates and critiques the studies of Chinese imperial law in line with Edward Said’s proposition of ‘Orientalism’. It identifies three major stages: the classical legal Orientalism, emphasising the heterogeneity of Chinese and Western laws based on Western values; the ‘neo-legal Orientalism’, stressing the homogeneity of the two by taking Western culture also as the assessment standard; and Oriental legalism, seeking Chinese subjectivity with Chinese perspectives and resources. The changes of the paradigms in assessing the legal culture in pre-republican China are related to the general intellectual transformations in the contemporary world. This essay proposes the approach of ‘confluent legalism’ that features drawing on diverse cultural essences of various nations in the world
Measurement of the Taylor scale in a magnetized turbulent laboratory plasma wind-tunnel
Get PDFThe fluid Taylor scale is measured in the Bryn Mawr Experiment (BMX) of the Bryn Mawr Plasma Laboratory and examined as a potential dissipation scale of magnetic turbulence within the plasma. We present the first laboratory measurements of the Taylor scale of a turbulent magnetized plasma through multi-point correlations of broadband magnetic fluctuations. From spatial and temporal correlations, respectively, the measured Taylor scales are 261 and 361 cm. These measurements are on the same order of magnitude as estimated ion dissipation scales within the BMX plasma with ion inertial scales between 1 and 10 cm and ion gyroscales between 0:1 and 1:0 cm. From these measurements, a magnetic Reynolds number can be computed. Since Taylor scale values are determined using multi-point correlations and a Richardson extrapolation technique, an estimate of the magnetic Reynolds number can be found without the added complication of specifying a model of microscopic diffusivity, a parameter often difficult to obtain experimentally
A 5000-year record of relative sea-level change in New Jersey, USA
No full textStratigraphic data from salt marshes provide accurate reconstructions of Holocene relative sea-level (RSL) change and necessary constraints to models of glacial isostatic adjustment (GIA), which is the dominant cause of Late-Holocene RSL rise along the U.S. mid-Atlantic coast. Here, we produce a new Mid- to Late-Holocene RSL record from a salt marsh bordering Great Bay in southern New Jersey using basal peats. We use a multi-proxy approach (foraminifera and geochemistry) to identify the indicative meaning of the basal peats and produce sea-level index points (SLIPs) that include a vertical uncertainty for tidal range change and sediment compaction and a temporal uncertainty based on high precision Accelerator Mass Spectrometry radiocarbon dating of salt-marsh plant macrofossils. The 14 basal SLIPs range from 1211 ± 56 years BP to 4414 ± 112 years BP, which we combine with published RSL data from southern New Jersey and use with a spatiotemporal statistical model to show that RSL rose 8.6 m at an average rate of 1.7 ± 0.1 mm/year (1σ) from 5000 years BP to present. We compare the RSL changes with an ensemble of 1D (laterally homogenous) and site-specific 3D (laterally heterogeneous) GIA models, which tend to overestimate the magnitude of RSL rise over the last 5000 years. The continued discrepancy between RSL data and GIA models highlights the importance of using a wide array of ice model and viscosity model parameters to more precisely fit site-specific RSL data along the U.S. mid-Atlantic coast
Dative Epitaxy of Commensurate Monocrystalline Covalent van der Waals Moiré Supercrystal
Get PDFRealizing van der Waals (vdW) epitaxy in the 1980s represents a breakthrough that circumvents the stringent lattice matching and processing compatibility requirements in conventional covalent heteroepitaxy. However, due to the weak vdW interactions, there is little control over film qualities by the substrate. Typically, discrete domains with a spread of misorientation angles are formed, limiting the applicability of vdW epitaxy. Here, the epitaxial growth of monocrystalline, covalent Cr5Te8 2D crystals on monolayer vdW WSe2 by chemical vapor deposition is reported, driven by interfacial dative bond formation. The lattice of Cr5Te8, with a lateral dimension of a few tens of micrometers, is fully commensurate with that of WSe2 via 3 × 3 (Cr5Te8)/7 × 7 (WSe2) supercell matching, forming a single-crystalline moiré superlattice. This work establishes a conceptually distinct paradigm of thin-film epitaxy, termed “dative epitaxy”, which takes full advantage of covalent epitaxy with chemical bonding for fixing the atomic registry and crystal orientation, while circumventing its stringent lattice matching and processing compatibility requirements; conversely, it ensures the full flexibility of vdW epitaxy, while avoiding its poor orientation control. Cr5Te8 2D crystals grown by dative epitaxy exhibit square magnetic hysteresis, suggesting minimized interfacial defects that can serve as pinning sites
Speech and Enchantment in Early Greek Thought from the Archaic to the Hellenistic Period
Get PDFWhen describing complex aesthetic or cognitive experiences, speakers often reach for idiomatic language. For ancient Greeks, one major cache of idiomatic terms comes from the language of enchantment. This dissertation accounts for how and why ancient Greeks used words related to θέλγω, κηλέω, γοητεία, μαγεία, μαγγανεία, ἐπῳδή, and ψυχαγωγία as a way of describing the effects of speech and song. Examination is given to writers from the Archaic to the Hellenistic period. Most important are Gorgias of Leontini, Plato, and Philodemus, who each remark in detail about the experience of enchantment. The study reveals that Greek writers use the language of enchantment to underscore a wide variety of effects that speech and song have on mind and body. These effects can include the feelings of being gripped by a narrative, moved by the sounds of a poem, or dumbstruck by a philosophical argument. Different writers provide their own fascinating and idiosyncratic ways of conceptualizing the psychology of these ‘enchantments.’ However, what unifies all accounts is a common motivation to avoid domesticating these aesthetic or cognitive effects with a technical or familiar vocabulary and, instead, to use the language of magic as a way of granting these effects asylum from the ordinary
What you and we say about me: How small shifts in language reveal and empower fundamental shifts in perspective
Get PDFOne of the most fundamental, yet often overlooked, compo-nents of language is the personal pronoun system. Pronouns reveal and empower different perspectives, providing insight into and even altering how a person is conceptualiz-ing the self. Here, we illustrate how the pronouns “I,” “you,” and “we” can enable shifts in perspective that bring a person further from, or closer to, others. We additionally highlight the implications of these pronoun shifts on the address-ee(s). We review a growing body of research that focuses on how these words can function as both windows—provid-ing insight into the thoughts and emotions of a speaker, and levers—that can subtly alter the speaker\u27s and addressee(s)’ thoughts, emotions, and even behaviors, across a range of domains. We conclude by discussing possibilities for future research
Topological spin memory of antiferromagnetically coupled skyrmion pairs in Co/Gd/Pt multilayers
Get PDFAntiferromagnetically (AFM) coupled skyrmions offer potential advantages for spintronic devices, including reduced dipolar fields that may enable smaller skyrmion sizes and a reduction of the skyrmion Hall effect. However, the topological stability of AFM-coupled skyrmions subjected to dramatic spin deformation through low-temperature cycling has not been investigated. Here we report the discovery of a topological spin memory effect for AFM-coupled skyrmion pairs in [Co/Gd/Pt]10 multilayered films. Photoemission electron microscopy imaging shows that bubble skyrmions in the multilayer that are stable at room temperature evolve into complex in-plane spin textures as the temperature is lowered and reform completely when the sample is warmed back up. Simulations demonstrate that Dzyaloshinskii-Moriya interactions play a key role in this spin memory effect, and furthermore reveal that the topological charge is preserved throughout the dramatic spin texture rearrangement and recovery. These results highlight a key aspect of topological protection—the preservation of the topological properties under continuous deformation—and also provide a promising avenue for information encryption and recovery
Social-contextual factors interact with masculinity to influence college men\u27s HPV vaccination intentions: The role of descriptive norms, prototypes, and physician gender
Get PDFMen’s low HPV vaccination uptake and HPV-related disease incidence are public health issues; gendered social–contextual factors likely play a role. In Study 1, college men (N = 130; Mage = 19.55; white = 58.1%) reported their social cognitions (male-referent descriptive norms and prototypes), self-reliance masculinity ideology, and vaccination intentions. In Study 2, college men (N = 106; Mage = 19.32; white = 61.3%) were randomly assigned to receive HPV vaccination information from a man or woman physician-avatar. Descriptive norms and favorable prototypes (bs ≥ .337; ps ≤ .016) were associated with higher HPV vaccination intentions. Men with higher self-reliance masculinity had higher HPV vaccination intentions with a man physician and when they perceived greater vaccination among men (ps ≤ .035). Men with higher self-reliance masculinity are more sensitive to gendered social–contextual effects in HPV vaccination decision-making. Gendered social–contextual factors should be integrated into public health interventions to increase college men’s HPV vaccination uptake