6,227 research outputs found
Vadim Kuznetsov. Informal Biography by Eyes of His First Adviser
The paper is dedicated to the memory of prominent theoretical physicist and
mathematician Dr. Vadim Kuznetsov who worked, in particular, in the fields of
the nonlinear dynamics, separation of variables, integrability theory, special
functions. It includes his short research biography, an account of the start of
his research career and the list of publications.Comment: This is a contribution to the Vadim Kuznetsov Memorial Issue on
Integrable Systems and Related Topics, published in SIGMA (Symmetry,
Integrability and Geometry: Methods and Applications) at
http://www.emis.de/journals/SIGMA
Some Spacetimes with Higher Rank Killing-Stackel Tensors
By applying the lightlike Eisenhart lift to several known examples of
low-dimensional integrable systems admitting integrals of motion of
higher-order in momenta, we obtain four- and higher-dimensional Lorentzian
spacetimes with irreducible higher-rank Killing tensors. Such metrics, we
believe, are first examples of spacetimes admitting higher-rank Killing
tensors. Included in our examples is a four-dimensional supersymmetric pp-wave
spacetime, whose geodesic flow is superintegrable. The Killing tensors satisfy
a non-trivial Poisson-Schouten-Nijenhuis algebra. We discuss the extension to
the quantum regime
On the possibility of revealing the transition of a baryon pair state to a six-quark confinement state
Proton-proton collisions are considered to find favourable conditions for
searching for the transition of a baryon pair state to a hexa-quark confinement
state . It is admitted that central
collisions in a definite range of the initial energy can lead to creation of an
intermediate compound system where the hexa-quark dibaryon can be formed.
Criteria for selection of central collision events and for manifestation of the
quark-structure dibaryon production are proposed.Comment: 7 pages, 2 figure
Cops vs. Gambler
We consider a variation of cop vs.\ robber on graph in which the robber is
not restricted by the graph edges; instead, he picks a time-independent
probability distribution on and moves according to this fixed
distribution. The cop moves from vertex to adjacent vertex with the goal of
minimizing expected capture time. Players move simultaneously. We show that
when the gambler's distribution is known, the expected capture time (with best
play) on any connected -vertex graph is exactly . We also give bounds on
the (generally greater) expected capture time when the gambler's distribution
is unknown to the cop.Comment: 6 pages, 0 figure
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