12,976 research outputs found
Secondary Quantum Hamiltonian Reduction
Recently, it has been shown how to perform the quantum hamiltonian reduction
in the case of general embeddings into Lie (super)algebras, and in the
case of general embeddings into Lie superalgebras. In another
development it has been shown that when and are both subalgebras of a
Lie algebra with , then classically the algebra can
be obtained by performing a secondary hamiltonian reduction on . In
this paper we show that the corresponding statement is true also for quantum
hamiltonian reduction when the simple roots of can be chosen as a subset
of the simple roots of . As an application, we show that the quantum
secondary reductions provide a natural framework to study and explain the
linearization of the algebras, as well as a great number of new
realizations of algebras.Comment: 33 pages, LATEX. Final version, including proof of conjecture.
Accepted for publication in Comm. Math. Phy
Combinatorial Structure of the Deterministic Seriation Method with Multiple Subset Solutions
Seriation methods order a set of descriptions given some criterion (e.g.,
unimodality or minimum distance between similarity scores). Seriation is thus
inherently a problem of finding the optimal solution among a set of
permutations of objects. In this short technical note, we review the
combinatorial structure of the classical seriation problem, which seeks a
single solution out of a set of objects. We then extend those results to the
iterative frequency seriation approach introduced by Lipo (1997), which finds
optimal subsets of objects which each satisfy the unimodality criterion within
each subset. The number of possible solutions across multiple solution subsets
is larger than , which underscores the need to find new algorithms and
heuristics to assist in the deterministic frequency seriation problem.Comment: 8 pages, 2 figure
Seasonal Biomass and Carbohydrate Allocation Patterns in Southern Minnesota Curlyleaf Pondweed Populations
Four southern Minnesota populations of curlyleaf pondweed
(
Potamogeton crispus
L.) were sampled monthly from
January 2001 to November 2002 to determine seasonal phenological,
biomass, and carbohydrate allocation patterns.
Low periods of carbohydrate storage in the seasonal phenological
cycle indicate potentially vulnerable periods in the
plant’s life cycle and may be the ideal time to initiate management
and control efforts
Seeding of Strange Matter with New Physics
At greater than nuclear densities, matter may convert into a mixture of
nucleons, hyperons, dibaryons, and strangelets, thus facilitating the formation
of strange matter even before the onset of the quark-matter phase transition.
From a nonstrange dibaryon condensate, it may even be possible to leapfrog into
strange matter with a certain new interaction, represented by an effective
six-quark operator which is phenomenologically unconstrained.Comment: 7 pages, no figure (Talk given at SQM97
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