Extensions of the fractional Brownian fields are constructed over
a complete Riemannian manifold. This construction is carried out for the full
range of the Hurst parameter α ∈ (0, 1). In particular, we establish existence,
distributional scaling (self-similiarity), stationarity of the increments, and almost
sure H¨older continuity of sample paths....
Let X and Y be a pair of smooth manifolds, each obtainable
from the other by surgery in codimension at least three. We show that the
corresponding spaces Riem⁺(X) and Riem⁺(Y), respectively consisting of
Riemannian metrics of positive scalar curvature on X and Y, are homotopy
equivalent. This result is...
The convolution inequality h ∗ h(ξ) ≤ B|ξ|θh(ξ) defined on Rⁿ
arises from a probabilistic representation of solutions of the n-dimensional
Navier-Stokes equations, n ≥ 2. Using a chaining argument, we establish
in all dimensions n ≥ 1 the nonexistence of strictly positive fully supported
solutions of this inequality for...
The surgery technique of Gromov and Lawson may be used to construct families of positive scalar curvature metrics which are parameterised by Morse functions. This has played an important role in the study of the space of metrics of positive scalar curvature on a smooth manifold and its corresponding moduli...
For each Cantor set C in R³, all points of which have bounded local genus, we show that there are infinitely many inequivalent Cantor sets in R³ with the complement having the same fundamental group as the complement of C. This answers a question from Open Problems in Topology and...
In this paper we extend the results of the research started by the first author in which Karlin-McGregor diagonalization of certain reversible Markov chains over countably infinite general state spaces by orthogonal polynomials was used to estimate the rate of convergence to a stationary distribution. We use a method of...
Given two rational maps φ and ψ on Ρ¹ of degree at least two, we study a symmetric, nonnegative real-valued pairing〈φ, ψ〉which is closely related to the canonical height functions hφ and hψ associated to these maps. Our main results show a strong connection between the value of〈φ, ψ〉and the...
Importance sampling algorithms are discussed in detail, with an emphasis on implicit sampling, and applied to data assimilation via particle filters. Implicit sampling makes it possible to use the data to find high-probability samples at relatively low cost, making the assimilation more efficient. A new analysis of the feasibility of...
We address the long-time behavior of a non-rotational von Karman plate in an inviscid potential flow. The model arises in aeroelasticity and models the interaction between a thin, nonlinear panel and a flow of gas in which it is immersed [6, 21, 23]. Recent results in [16, 18] show that...
We consider flow-structure interactions modeled by a modified wave equation coupled at an interface with equations of nonlinear elasticity. Both subsonic and supersonic flow velocities are treated with Neumann type flow conditions, and a novel treatment of the so called Kutta-Joukowsky flow conditions are given in the subsonic case. The...