The Phase Structure of the Weakly Coupled Lattice Schwinger Model

The weak coupling expansion is applied to the single flavour Schwinger model with Wilson fermions on a symmetric toroidal lattice of finite extent. We develop a new analytic method which permits the expression of the partition function as a product of pure gauge expectation values whose zeroes are the Lee-Yang zeroes of the model. Application of standard finite-size scaling techniques to these zeroes recovers previous numerical results for the small and moderate lattice sizes to which those studies were restricted. Our techniques, employable for arbitrarily large lattices, reveal the absence of accumulation of these zeroes on the real hopping parameter axis at constant weak gauge coupling. The consequence of this previously unobserved behaviour is the absence of a zero fermion mass phase transition in the Schwinger model with single flavour Wilson fermions at constant weak gauge coupling.Comment: 8 pages, 2 figures, insert to figure 2 include

The Structure of the Aoki Phase at Weak Coupling

A new method to determine the phase diagram of certain lattice fermionic field theories in the weakly coupled regime is presented. This method involves a new type of weak coupling expansion which is multiplicative rather than additive in nature and allows perturbative calculation of partition function zeroes. Application of the method to the single flavour Gross-Neveu model gives a phase diagram consistent with the parity symmetry breaking scenario of Aoki and provides new quantitative information on the width of the Aoki phase in the weakly coupled sector.Comment: 9 pages, 1 figure (minor changes) To be published in Phys. Lett.

Orbiting Geophysical Observatory Attitude Control Subsystem Design Survey. NASA/ERC Design Criteria Program, Guidance and Control

This design survey summarizes the history of the Orbiting Geophysical Observatories' (OGO) Attitude Control Subsystem (ACS) from the proposal phase through current flight experience. Problems encountered in design, fabrication, test, and on orbit are discussed. It is hoped that the experiences of the OGO program related here will aid future designers

Orbiting Geophysical Observatory Attitude Control Subsystem design survey

Development history and design modifications for attitude control subsystem of OG

Down In The Old Neighborhood : Waltz

https://digitalcommons.library.umaine.edu/mmb-vp/7220/thumbnail.jp

Grade school in relation to Lithology and chemistry in the Northampton sand and Frodingam ironstones

Not availabl

Universal Amplitude Ratios in the Ising Model in Three Dimensions

We use a high-precision Monte Carlo simulation to determine the universal specific-heat amplitude ratio A+/A- in the three-dimensional Ising model via the impact angle \phi of complex temperature zeros. We also measure the correlation-length critical exponent \nu from finite-size scaling, and the specific-heat exponent \alpha through hyperscaling. Extrapolations to the thermodynamic limit yield \phi = 59.2(1.0) degrees, A+/A- = 0.56(3), \nu = 0.63048(32) and \alpha = 0.1086(10). These results are compatible with some previous estimates from a variety of sources and rule out recently conjectured exact values.Comment: 17 pages, 5 figure

The Site-Diluted Ising Model in Four Dimension

In the literature, there are five distinct, fragmented sets of analytic predictions for the scaling behaviour at the phase transition in the random-site Ising model in four dimensions. Here, the scaling relations for logarithmic corrections are used to complete the scaling pictures for each set. A numerical approach is then used to confirm the leading scaling picture coming from these predictions and to discriminate between them at the level of logarithmic corrections.Comment: 15 pages, 5 ps figures. Accepted for publication in Phys. Rev.

Evaluating smart city learning

Measurement and analysis of individually interpreted learning experiences can build a knowledge picture of how learners perceive immersive technology-mediated learning in smart cities. Comparison of these learning experiences, with theoretical factors derived from relevant literature, may then shed light on the usefulness of theory in practical learning design and approaches to the evaluation of immersive learning environments analysed from a theoretical basis. In turn, this may contribute to current approaches of urban smart city environment planning for citizen engaged ‘human smart cities’ [14]. Mobile learning location-based prototypes will be developed with subject experts and implemented in open (urban) spaces located at Upper Barrakka Gardens, Valletta for history and Argotti Gardens, Floriana for botany. This paper discusses potential methodologies for designing a measurement of the effectiveness of these learning experiences and associated learning design for immersive urban learning environments mediated by mobile and networked technologies. Acknowledging the hybrid nature [9] of smart city learning, interactions between digital tools, content and community, measuring both intra- and inter-learner experiences is anticipated. Identifying and quantifying these dimensions of interactions will help us understand more about how urban smart learning activities create immersive experiences for each learner, engaging them in a variety of internal cognitive and social processes. To clarify mutual interaction between theoretical and empirical factors, a system of theoretical factors of significance is proposed to be developed, and then correlated, with learning experience analysis factors. A brief review of hybrid learning environment research, including ubiquitous learning [4] manifested in hybrid [9], mobile [8] and smart city [2] environments, provides context for how analytical methodology might be applied to an interactive learning system in smart cities. Phenomenographic techniques of variation and outcome space are investigated, together with the Dialogic Space concept [30] of conversation interaction for analysing dialogues.Funded by the Horizon 2020 Framework Programme of the European Union.peer-reviewe

The Logarithmic Triviality of Compact QED Coupled to a Four Fermi Interaction

This is the completion of an exploratory study of Compact lattice Quantum Electrodynamics with a weak four-fermi interaction and four species of massless fermions. In this formulation of Quantum Electrodynamics massless fermions can be simulated directly and Finite Size Scaling analyses can be performed at the theory's chiral symmetry breaking critical point. High statistics simulations on lattices ranging from $8^4$ to $24^4$ yield the equation of state, critical indices, scaling functions and cumulants. The measurements are well fit with the orthodox hypothesis that the theory is logarithmically trivial and its continuum limit suffers from Landau's zero charge problem.Comment: 27 pages, 15 figues and 10 table