Multiple Schramm-Loewner Evolutions and Statistical Mechanics Martingales

A statistical mechanics argument relating partition functions to martingales is used to get a condition under which random geometric processes can describe interfaces in 2d statistical mechanics at criticality. Requiring multiple SLEs to satisfy this condition leads to some natural processes, which we study in this note. We give examples of such multiple SLEs and discuss how a choice of conformal block is related to geometric configuration of the interfaces and what is the physical meaning of mixed conformal blocks. We illustrate the general ideas on concrete computations, with applications to percolation and the Ising model.Comment: 40 pages, 6 figures. V2: well, it looks better with the addresse

Mean-Field Theory of Feshbach-Resonant Interactions in 85Rb Condensates

Recent Feshbach-resonance experiments with 85Rb Bose-Einstein condensates have led to a host of unexplained results: dramatic losses of condensate atoms for an across-resonance sweep of the magnetic field, a collapsing condensate with a burst of atoms emanating from the remnant condensate, increased losses for decreasing interaction times-- until short times are reached, and seemingly coherent oscillations between remnant and burst atoms. Using a simple yet realistic mean-field model, we find that rogue dissociation, molecular dissociation to noncondensate atom pairs, is strongly implicated as the physical mechanism responsible for these observations.Comment: v2: numbers changed, not conclusions; 5 pages, 3 figures, submitted to PR

Shortcut to a Fermi-Degenerate Gas of Molecules via Cooperative Association

We theoretically examine the creation of a Fermi-degenerate gas of molecules via a photoassociation or Feshbach resonance applied to a degenerate Bose-Fermi mixture of atoms. This problem raises an interest because, unlike bosons, fermions in general do not behave cooperatively, so that the collective conversion of, say, two million atoms into one million molecules is not to be expected. Nevertheless, we find that the coupled Fermi system displays collective Rabi-like oscillations and adiabatic passage between atoms and molecules, thereby mimicking Bose-Einstein statistics. Cooperative association of a degenerate mixture of Bose and Fermi gases could therefore serve as a shortcut to a degenerate gas of Fermi molecules.Comment: 4 pages, 2 figures, submitted to PRL; v2: expanded intro, added discussion on neglect of collisions and when mimicking should occu

Properties and Gratifications of Mobile Data Services: An Explorative Investigation

We identify, explore and categorize mobile service qualities (properties) and their valuations as gratifications based on a longitudinal field study of mobile data service use. Different properties - instrumental, aesthetic, and expressive - and service gratifications - content, process, and social - salient for various data services are identified during users\u27 mobile service experience. Service properties and gratifications offer a means to track, garner and organize multiple accounts of a mobile service and its value from a user\u27s point of view. The findings complement current technology acceptance theory by showing how artifact\u27s properties and its use gratifications shape and influence either continuation and expansion, or discontinuation of mobile data service use

Homogenisation of Biocultural Diversity: Plant Ethnomedicine and Its Diachronic Change in Setomaa and Võromaa, Estonia, in the Last Century

When studying the evolution of the use of medicinal plants, it is important to identify what role, and to what extent, external factors and local biocultural diversities play in shaping cultural changes. We chose as a case study, which forms part of a larger project, a religiously and linguistically distinct group, the Seto, and compared their current and past plant use with that of the surrounding Võro. Ethnobotanical fieldwork was conducted in the summers of 2018 and 2019. Current uses of plants constituted 34% of the total registered use reports and 41% of those were used to treat general diseases or used as prophylactics. In total, the medicinal use of 86 taxa was recorded, and of these 48 were prevalent. Strong erosion (the abandonment of 43, mainly wild taxa used historically) and valorisation of the uses shared with neighboring as well as distant regions once part of the Soviet Union, were evident, signalling the potential influence of the centralised distribution of knowledge. The results clearly show that the plant medicine-related biocultural diversities of the two groups have been considerably homogenised, eroded and influenced by the knowledge spread through various means during the Soviet era and over the last 30 years