295 research outputs found
From the Plateau problem to periodic minimal surfaces in lipids, surfactants and diblock copolymers
We present the novel method for generation of periodic surfaces based on the
simple Landau-Ginzburg model of microemulsion. We test the method on four
minimal surfaces (P,D,G, and I-WP), find two new surfaces of cubic symmetry,
show how to obtain periodic surfaces of high genus and n-tuply-continuous
phases. We point that the Landau model used here should be generic for all
systems characterized by internal interfaces, including the diblock copolymer
systems.Comment: 15 pages, Plain TeX , figures available on request or at
http://saka.ichf.edu.pl/WTGRH/surfaces.htm
Atomic Nuclei with Tetrahedral and Octahedral Symmetries
We present possible manifestations of octahedral and tetrahedral symmetries
in nuclei. These symmetries are associated with the OhD and TdD double point
groups. Both of them have very characteristic finger-prints in terms of the
nucleonic level properties - unique in the Fermionic universe. The tetrahedral
symmetry leads to the four-fold degeneracies in the nucleonic spectra; it does
not preserve the parity. The octahedral symmetry leads to the four-fold
degeneracies in the nucleonic spectra as well but it does preserve the parity.
Microscopic predictions have been obtained using mean-field theory based on
the relativistic equations and confirmed by using 'traditional' Schroedinger
equation formalism. Calculations are performed in multidimensional deformation
spaces using newly designed algorithms.
We discuss some experimental fingerprints of the hypothetical new symmetries
and possibilities of their verification through experiments.Comment: 24 pages, LaTeX, Invited lecture on the XXXVII School of Nuclear
Physics, Zakopane 2002, Polan
Quantum rotors and their symmetries
A connection between nuclear symmetries other than those of an ellipsoidal
nucleus and the properties of the implied rotational spectra are discussed. The
discussion is focussed on a few examples of exotic shapes predicted recently by
microscopic calculations. Some possible interpretation difficulties related to
experiment are shortly mentioned.Comment: Invited talk at "High Spin Physics 2001", see
http://www.fuw.edu.pl/~hs2001/ , to be published in Acta Physica Polonica
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