Nonlinear algebra and applications
We showcase applications of nonlinear algebra in the sciences and engineering. Our review
is organized into eight themes: polynomial optimization, partial differential equations …
is organized into eight themes: polynomial optimization, partial differential equations …
Moment ratio inequality of bivariate Gaussian distribution and three-dimensional Gaussian product inequality
O Russell, W Sun - Journal of Mathematical Analysis and Applications, 2023 - Elsevier
We prove the three-dimensional Gaussian product inequality (GPI) E [X 1 2 X 2 2 m 2 X 3 2
m 3]≥ E [X 1 2] E [X 2 2 m 2] E [X 3 2 m 3] for any centered Gaussian random vector (X 1, X …
m 3]≥ E [X 1 2] E [X 2 2 m 2] E [X 3 2 m 3] for any centered Gaussian random vector (X 1, X …
Using sums-of-squares to prove Gaussian product inequalities
O Russell, W Sun - Dependence Modeling, 2024 - degruyter.com
The long-standing Gaussian product inequality (GPI) conjecture states that E [∏ j= 1 n∣ X
j∣ yj]≥∏ j= 1 n E [∣ X j∣ yj] for any centered Gaussian random vector (X 1,…, X n) and …
j∣ yj]≥∏ j= 1 n E [∣ X j∣ yj] for any centered Gaussian random vector (X 1,…, X n) and …
Identifiability in continuous Lyapunov models
The recently introduced graphical continuous Lyapunov models provide a new approach to
statistical modeling of correlated multivariate data. The models view each observation as a …
statistical modeling of correlated multivariate data. The models view each observation as a …
Matroids on eight elements with the half-plane property and related concepts
M Kummer, B Sert - SIAM Journal on Discrete Mathematics, 2023 - SIAM
We classify all matroids with at most eight elements that have the half-plane property, and
we provide a list of some matroids on nine elements that have and that do not have the half …
we provide a list of some matroids on nine elements that have and that do not have the half …
Exact semidefinite programming bounds for packing problems
In this paper we give an algorithm to round the floating point output of a semidefinite
programming solver to a solution over the rationals or a quadratic extension of the rationals …
programming solver to a solution over the rationals or a quadratic extension of the rationals …
Symmetric nonnegative functions, the tropical Vandermonde cell and superdominance of power sums
We study nonnegative and sums of squares symmetric (and even symmetric) functions of
fixed degree. We can think of these as limit cones of symmetric nonnegative polynomials …
fixed degree. We can think of these as limit cones of symmetric nonnegative polynomials …
Time-dependent moments from partial differential equations and the time-dependent set of atoms
We study the time-dependent moments and associated polynomials arising from the partial
differential equation $\partial_t f=\nu\Delta f+ g\cdot\nabla f+ h\cdot f $, and consider in detail …
differential equation $\partial_t f=\nu\Delta f+ g\cdot\nabla f+ h\cdot f $, and consider in detail …
Bad projections of the PSD cone
The image of the cone of positive semidefinite matrices under a linear map is a convex cone.
Pataki characterized the set of linear maps for which that image is not closed. The Zariski …
Pataki characterized the set of linear maps for which that image is not closed. The Zariski …
The Lorenz system as a gradient-like system
JP Parker - arxiv preprint arxiv:2401.10649, 2024 - arxiv.org
We formulate, for continuous-time dynamical systems, a sufficient condition to be a gradient-
like system, ie that all bounded trajectories approach stationary points and therefore that …
like system, ie that all bounded trajectories approach stationary points and therefore that …