3,814 research outputs found
Measurement and self-adjoint operators
The approximations of classical mechanics resulting from quantum mechanics
are richer than a correspondence of classical dynamical variables with
self-adjoint Hilbert space operators. Assertion that classical dynamic
variables correspond to self-adjoint Hilbert space operators is disputable and
sets unnatural limits on quantum mechanics. Well known examples of classical
dynamical variables not associated with self-adjoint Hilbert space operators
are discussed as a motivation for the realizations of quantum field theory that
lack Hermitian field operators but exhibit interaction.Comment: 17 page
AGRO-ETHICS: EXTENSION, RESEARCH, AND TEACHING
Teaching/Communication/Extension/Profession,
On Universal Cycles for Multisets
A Universal Cycle for t-multisets of [n]={1,...,n} is a cyclic sequence of
integers from [n] with the property that each t-multiset of
[n] appears exactly once consecutively in the sequence. For such a sequence to
exist it is necessary that n divides , and it is reasonable
to conjecture that this condition is sufficient for large enough n in terms of
t. We prove the conjecture completely for t in {2,3} and partially for t in
{4,6}. These results also support a positive answer to a question of Knuth.Comment: 14 pages, two figures, will appear in Discrete Mathematics' special
issue on de Bruijn Cycles, Gray Codes and their generalizations; paper
revised according to journal referees' suggestion
Abandon Ship
The clear notes of the bugle sounding chow call came over the loudspeakers throughout the ship. I stood waiting in the mess line, formed topside on the main deck aft. The last rays of the sun caught the signal flags flying - gave them a brilliant cast of red, green and yellow. The new cruiser rolled in the huge swells, leaving a foaming white trail behind her.
The men stood silently gazing at the horizon. The ship gave a slight shudder each time one of the swells crashed into her.
The sharp clanging of the ship\u27s general-alarm bell, followed by the shrill call of the bugle, broke the silence. All hands, man your battle stations! blared from the loud speaker
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