Results 81 to 90 of about 12,561 (233)

Density‐Valued ARMA Models by Spline Mixtures

Journal of Time Series Analysis, EarlyView.
ABSTRACT This paper proposes a novel framework for modeling time series of probability density functions by extending autoregressive moving average (ARMA) models to density‐valued data. The method is based on a transformation approach, wherein each density function on a compact domain [0,1]d$$ {\left[0,1\right]}^d $$ is approximated by a B‐spline ...
Yasumasa Matsuda, Rei Iwafuchi
wiley   +1 more source

Integrable quadratic Hamiltonians on the Euclidean group of motions [PDF]

, 2010
In this paper, we discuss the problem of globally computing sub-Riemannian curves on the Euclidean group of motions SE(3). In particular, we derive a global result for special sub-Riemannian curves whose Hamiltonian satisfies a particular condition.
Biggs, James, Biggs, J.D., BIGGS, JAMES DOUGLAS, J. Biggs, W. Holderbaum, Holderbaum, W., Holderbaum, William, Biggs, J. D.   +7 more
core   +1 more source

Inverse problems for semilinear elliptic PDE with a general nonlinearity a(x,u)$a(x,u)$

Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.
Abstract This article studies the inverse problem of recovering a nonlinearity in an elliptic equation Δu+a(x,u)=0$\Delta u + a(x,u) = 0$ from boundary measurements of solutions. Previous results based on first‐order linearization achieve this under a sign condition on ∂ua(x,u)$\partial _u a(x,u)$, and results based on higher order linearization ...
David Johansson, Janne Nurminen, Mikko Salo   +2 more
wiley   +1 more source

Geodesic Monte Carlo on Embedded Manifolds [PDF]

, 2013
Markov chain Monte Carlo methods explicitly defined on the manifold of probability distributions have recently been established. These methods are constructed from diffusions across the manifold and the solution of the equations describing geodesic flows
Simon Byrne, Byrne, Simon, Byrne, S, Girolami, M, Mark Girolami, Girolami, Mark   +5 more
core   +1 more source

Invariant Measure and Universality of the 2D Yang–Mills Langevin Dynamic

Communications on Pure and Applied Mathematics, Volume 79, Issue 8, Page 1973-2102, August 2026.
ABSTRACT We prove that the Yang–Mills (YM) measure for the trivial principal bundle over the two‐dimensional torus, with any connected, compact structure group, is invariant for the associated renormalised Langevin dynamic. Our argument relies on a combination of regularity structures, lattice gauge‐fixing and Bourgain's method for invariant measures ...
Ilya Chevyrev, Hao Shen
wiley   +1 more source

Efficient Tensor Completion Algorithms for Highly Oscillatory Operators

Numerical Linear Algebra with Applications, Volume 33, Issue 4, August 2026.
ABSTRACT We address the problem of recovering highly oscillatory operators, represented as n×n$$ n\times n $$ matrices with a fixed set of observed entries. Given that these matrices can be well compressed by butterfly matrix decomposition of L=𝒪(logn) levels requiring only O(nlogn)$$ O\left(n\log n\right) $$ degrees of freedom, we propose a novel ...
Navjot Singh, Edgar Solomonik, Xiaoye Sherry Li, Yang Liu   +3 more
wiley   +1 more source

Conformality and Pseudo-Riemannian Manifolds.

MATHEMATICA SCANDINAVICA, 1971
Artykuł w: Annales Universitatis Mariae Curie-Skłodowska. Sectio A, Mathematica. Vol. 22/23/24 (1968/1969/1970), s. 113-123 ; streszcz. pol., ros. ; Artykuł w: Annales Universitatis Mariae Curie-Skłodowska. Sectio A, Mathematica. Vol. 22/23/24 (1968/1969/1970), s. 113-123 ; streszcz. pol., ros.
Ławrynowicz, Julian, Waliszewski, Włodzimierz (1934-2013)   +1 more
openaire   +3 more sources

Fubini‐Study Metric Tensor Evolution and Reduced State Distinguishability in Geometry‐Aware Optimization for Reliable Near‐Term Variational Quantum Eigensolvers

International Journal of Quantum Chemistry, Volume 126, Issue 13, July 5, 2026.
During optimization via the quantum natural gradient in a variational quantum eigensolver, the evolution of the Fubini‐Study metric suppresses irrelevant parameter directions and reduces state distinguishability near the ground state. ABSTRACT The lack of both a consistently effective and broadly reliable classical optimizer for variational quantum ...
Dwi Cahyo Mariyanto, Hadyan L. Prihadi, Angga Dito Fauzi, L. T. Handoko, Yanoar P. Sarwono, Rui‐Qin Zhang   +5 more
wiley   +1 more source

Degenerate Foliations in Sasakian Semi-Riemannian Manifolds [PDF]

In the Semi-Riemannian case we do not have the liability of the existence of such a metric being a difference from the Riemannian case. A Semi-Riemannian manifold provided with a normal contact metric structure is called Sasakian manifold.Semi-Riemannian,
Catalin Angelo Ioan
core   +1 more source

Fourier Expansion‐Based Approach to the Parameter Space of Classical Systems

Annalen der Physik, Volume 538, Issue 7, July 2026.
ABSTRACT We propose a new approach to compute the classical metric tensor (CMT) and the Hannay curvature using Fourier series expansions in action‐angle variables. This approach circumvents the need for complex time‐domain integrals or the construction of generating functions, replacing them with algebraic combinations of Fourier coefficients. We prove
Marcos J. Hernández, Daniel Gutiérrez‐Ruiz, Diego Gonzalez, J. David Vergara   +3 more
wiley   +1 more source