Flatness Properties of Acts: Some Examples

Research supported by Natural Sciences and Engineering Research Council of Canada Grant A4494 Research supported by Estonian Science Foundation Grant 930     

Symplectic homology via generating functions

Research at Mathematical Sciences Research Institute supported by an MSRI postdoctoral fellowship. Research at Stanford supported by an NSF Mathematical Sciences Postdoctoral Research Fellowship. Research at Centre Emile Borel, Institut Henri Poincaré, Paris funded by Ministère des Affaires Etrangères, France.     

A minimal cutset of the boolean lattice with almost all members

Two almost explicit constructions are given satisfying the title.This research was done while the authors visited the Institute for Mathematics and its Applications at the University of Minnesota, Minneapolis, MN 55455.Research supported in part by Hungarian National Foundation for Scientific Research, grant no. 1812.Research supported in part by NSF Grant MDS 87-01475.Research supported in part by NSF grant DMS 86-06225 and Airforce Grant OSR-86-0076.     

Jackson’s integral of the Hurwitz zeta function

We give a Jacksonq-integral analogue of Euler’s logarithmic sine integral established in 1769 from several points of view, specifically from the one relating to the Hurwitz zeta function. Partially supported by Grant-in-Aid for Exploratory Research No. 15654003. Partially supported by Grant-in-Aid for Scientific Research (B) No. 15340003. Partially supported by Grant-in-Aid for Scientific Research (B) No. 15340012.     

Stable mixed moving averages

Summary The class of (non-Gaussian) stable moving average processes is extended by introducing an appropriate joint randomization of the filter function and of the stable noise, leading to stable mixed moving averages. Their distribution determines a certain combination of the filter function and the mixing measure, leading to a generalization of a theorem of Kanter (1973) for usual moving averages. Stable mixed moving averages contain sums of independent stable moving averages, are ergodic and are not harmonizable. Also a class of stable mixed moving averages is constructed with the reflection positivity property.Research supported by AFSOR Contract 91-0030Research also supported by ARO DAAL-91-G-0176Research also supported by AFOSR 90-0168Research also supported by ONR N00014-91-J-0277     

A set of staircase linear programming test problems

A set of staircase linear programming test problems are made available for computational experiments.Research supported by the U.S. Department of Energy under contract DE-AC02-76CH00016.Research supported by the Belgian National Research Program in Energy, contract E/I/3.     

The rotation number and the herpolhode angle in Euler’s top

We describe the relation between the rotation number and the herpolhode angle in the rotation of the force-free rigid body.Received: September 23, 2002Research partially supported by NSERC.Research partially supported by European Community funding for the Research and Training Network MASIE (HPRN-CT-2000-00113).     

Some Geometrical Aspects of Efficient Points in Vector Optimization

We study efficient point sets in terms of extreme points, positive support points and strongly positive exposed points. In the case when the ordering cone has a bounded base, we prove that the efficient point set of a weakly compact convex set is contained in the closed convex hull of its strongly positive exposed points, thereby extending the Phelps theorem. We study also the density of positive proper efficient point sets. This research was supported by a Central Research Grant of Hong Kong Polytechnic University, Grant G-T 507. Research of the first author was also supported by the National Natural Science Foundation of P.R. China, Grant 10361008, and the Natural Science Foundation of Yunnan Province, China, Grant 2003A002M. Research of the second author was also supported by the Natural Science Foundation of Chongqing. Research of the third author was supported by a research grant from Australian Research Counsil.     

Isoperimetric inequalities for polarization and virtual mass

This paper is the continuation of a previous investigation. Here representations for the components of the virtual mass and polarization tensors in terms of boundary integrals are given and new isoperimetric inequalities for star-shaped bodies are derived. Research supported by NSF Grant, MCS 8300842. Research supported by Natural Sciences and Engineering Research Council Canada.     

On the complexity of approximating the maximal inscribed ellipsoid for a polytope

We give a new polynomial bound on the complexity of approximating the maximal inscribed ellipsoid for a polytope.Research supported by NSF Grant DMS-8706133.Research supported by NSF Grant DMS-8904406.     

The dimension of cycle-free orders

The existence of a four-dimensional cycle-free order is proved. This answers a question of Ma and Spinrad. Two similar problems are also discussed.Research partially supported by Office of Naval Research grant N00014-90-J-1206Research partially supported by the National Science Foundation under grant DMS     

The subgaussian constant and concentration inequalities

We study concentration inequalities for Lipschitz functions on graphs by estimating the optimal constant in exponential moments of subgaussian type. This is illustrated on various graphs and related to various graph constants. We also settle, in the affirmative, a question of Talagrand on a deviation inequality for the discrete cube. Research supported in part by NSF Grant No. DMS-0405587 and by EPSRC Visiting Fellowship. Research supported in part by NSF Grant No. DMS-9803239, DMS-0100289. Research supported in part by NSF Grant No. DMS-0401239.     

Finite rank operators with large trace

We give some estimates for how well the normalized trace functional exposes the identity map on a finite-dimensional space. Research supported by NSF Grant DMS-8320632. Research supported by NSF Grant DMS-8400960.     

Interlacing of zeros of shifted sequences of one-parameter orthogonal polynomials

We study the interlacing property of zeros of Laguerre polynomials of adjacent degree, where the free parameters differ by an integer, and of the same degree, where the free parameter is shifted continuously. Similar interlacing results are proven for the positive zeros of Gegenbauer polynomials. Research by Kathy Driver is supported by the National Research Foundation of South Africa under grant number 2053730. Research by Kerstin Jordaan is partially supported by the National Research Foundation of South Africa under grant number 2054423.     

Another approach to asymptotics and bootstrap of randomly trimmed means

A unified, empirical processes based approach to the central limit theorem and to the bootstrap for randomly trimmed and Winsorized means is developed, with emphasis on Hampel's means. Research partially supported by the Center for Research, College of Science and Health, and by the ART program of the William Paterson University. Research partially supported by NSF Grant No. DMS-0070382.     

Limit theorems for sums of dependent random variables occurring in statistical mechanics

Summary By the use of conditioning, we extend previously obtained results on the asymptotic behavior of partial sums for certain triangular arrays of dependent random variables, known as Curie-Weiss models. These models arise naturally in statistical mechanics. The relation of these results to multiple phases, metastable states, and other physical phenomena is explained.Alfred P. Sloan Research Fellow. Research supported in part by National Science Foundation Grant MPS 76-06644A01Alfred P. Sloan Research Fellow. Research supported in part by National Science Foundation Grant MCS 77-20683 and by U.S.-Israel Binational Science FoundationResearch supported in part by National Science Foundation Grant PHY77-02172     

Aperiodic tilings of the hyperbolic plane by convex polygons

Several aperiodic hyperbolic tiling systems consisting of a single convex tile are constructed. Research partially supported by GIF grant no. G-454.213.06.95 and SFB 343 Bielefeld. The work of the first author was supported in part by NSF grant DMS-9424613. The work of the second author was supported in part by a grant of the Israel Academy of Sciences, and by the Edmund Landau Center for Research in Mathematical Analysis supported by the Minerva Foundation (Federal Republic of Germany).     

An elementary and direct proof of the Painlevé property for the Painlevé equations I,II and IV

We present a direct and elementary proof that all the solutions of the Painlevé Equations I, II and IV are meromorphic functions on the whole complex plane. The proof uses some ideas from the existing proofs but applies the ideas in a different setting. Research was supported by Hong Kong Research Grant Council Earmark Grant HKUST6123/00P. Research was supported by Hong Kong Research Grant Council Earmark Grant HKUST6107/02P.     

Separating the solution sets of analytical and polynomial systems

A linear inequality system with infinitely many constraints is polynomial (analytical) if its index set is a compact interval of the real line and all its coefficients are polynomial (analytical, respectively) functions of the index on this interval. This paper provides an example of analytical system whose solution set cannot be the solution set of any polynomial system. Research supported by DGES of Spain and FEDER of UE, Grant BFM2002-04114-C02-01. Research supported by CONACyT of Mexico, Grant 130036. Research partially supported by CONACyT of Mexico, Grant 44003.     

The scalar curvature equation on 2- and 3-spheres

In this article we obtain a priori estimates for solutions to the prescribed scalar curvature equation on 2- and 3-spheres under a nondegeneracy assumption on the curvature function. Using this estimate, we use the continuity method to demonstrate the existence of solutions to this equation when a map associated to the given curvature function has non-zero degree.Research of first author supported in part by NSF grant 91-03949Research of second author supported by a NSF Postdoctoral Fellowship.Research of third author supported in part by NSF grant 91-02872 and the Ellentuck Fund.