521 research outputs found
Monodromy zeta functions at infinity, Newton polyhedra and constructible sheaves
By using sheaf-theoretical methods such as constructible sheaves, we
generalize the formula of Libgober-Sperber concerning the zeta functions of
monodromy at infinity of polynomial maps into various directions. In
particular, some formulas for the zeta functions of global monodromy along the
fibers of bifurcation points of polynomial maps will be obtained.Comment: 31 pages; revise
Quenched Invariance Principle for a Reflecting Diffusion in a Continuum Percolation Cluster
We consider a continuum percolation built over stationary ergodic point
processes. Assuming that the occupied region has a unique unbounded cluster and
the cluster satisfies volume regularity and isoperimetric condition, we prove a
quenched invariance principle for reflecting diffusions on the cluster.Comment: 26 page
CP,T and/or CPT Violations in the K0-K0bar System --Implications of the KTeV,NA48 and CPLEAR Results
Possible violation of CP, T and/or CPT symmetries in the \ko-\kob system
is studied from a phenomenological point of view. For this purpose, we first
introduce parameters which represent violation of these symmetries in mixing
parameters and decay amplitudes in a convenient and well-defined way and,
treating these parameters as small, derive formulas which relate them to the
experimentally measured quantities. We then perform numerical analyses, with
the aid of the Bell-Steinberger relation, to derive constraints to these
symmetry-violating parameters, firstly paying particular attention to the
results reported by KTeV Collaboration and NA48 Collaboration, and then with
the results reported by CPLEAR Collaboration as well taken into account. A case
study, in which either CPT symmetry or T symmetry is assumed, is also carried
out. It is demonstrated that CP and T symmetries are violated definitively at
the level of 10^{-4} in decays and presumably at the level of 10^{-3} in
the \ko-\kob mixing, and that the Bell-Steinberger relation helps us to
establish CP and T violations being definitively present in the \ko-\kob
mixing and to test CPT symmetry to a level of 10^{-4} ~ 10^{-5}.Comment: 21 pages, 1 figure
A geometric degree formula for A-discriminants and Euler obstructions of toric varieties
AbstractWe give explicit formulas for the dimensions and the degrees of A-discriminant varieties introduced by Gelfand, Kapranov and Zelevinsky. Our formulas can be applied also to the case where the A-discriminant varieties are higher-codimensional and their degrees are described by the geometry of the configurations A. Moreover combinatorial formulas for the Euler obstructions of general (not necessarily normal) toric varieties will be also given
An Index to the Poems of Alfred Edward Housman (Part 2) : Last Poems, More Poems, and Collected Poems A-Q
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