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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 55 records · Page 3

Exact bosonization in two spatial dimensions and a new class of lattice gauge theories

We describe a 2d analog of the Jordan–Wigner transformation which maps an arbitrary fermionic system on a 2d lattice to a lattice gauge theory while preserving the locality of the Hamiltonian. When the space is simply-connected, this bosonization map is an equivalence. We describe several examples of 2d bosonization, including free fermions on square and honeycomb lattices and the Hubbard model. We describe Euclidean actions for the corresponding lattice gauge theories and find that they contain Chern–Simons-like terms. Finally, we write down a fermionic dual of the gauged Ising model (the Fradkin–Shenker model).

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Effects of microwave and ultrasound exposure to microsphere particles made out of different classes of inorganic and organic materials

In this study polymer, metal oxide and polymer-PZT composite microsphere materials were prepared by either hydrothermal or microwave assisted methods. Materials were subjected to microwave and ultrasound irradiation under specific conditions in order to understand their mechanical stability and morphological changes in dimensions. Scanning electron microscopy imaging was carried out before and after each irradiation and clear differences were observed depending on irradiation method and sample composition.

36 MATERIALS SCIENCE↗