arXiv subjects

Haoyang Ji

Publications and source records attributed to Haoyang Ji.

4 recordsLinked to original sources

arXiv2026

Stochastic stability for weakly hyperbolic contracting Lorenz maps

In this article we study the expanding properties of random perturbations of contracting Lorenz maps satisfying the summability condition of exponent 1. Under general conditions on the maps and perturbation types, we prove stochastic stability in the strong sense: convergence of the densities of the stationary measures to the density of the physical measure of the unperturbed map in the $L^1$-norm. This improves the main result in \cite{Me}.

math.DS↗

arXiv2026

The non-topological $Z^\prime$ string in the 331 model and its classical stability

We study the classical stability of a non-topological $Z^\prime$ string in the minimal 331 model, which arises from the maximal symmetry breaking pattern of an ${\rm SU}(6)$ toy model. Two Higgs triplets are introduced according to the emergent global symmetries in the fermionic sector of the ${\rm SU}(6)$ toy model, which will achieve the sequential symmetry breaking of ${\rm SU}(3)_c\otimes {\rm SU}(3)_W \otimes {\rm U}(1)_X\to {\rm SU}(3)_c\otimes {\rm SU}(2)_W \otimes {\rm U}(1)_Y$. By analyzing small perturbations around the string background and solving the coupled Helmholtz equations numerically, we find that the string is stable only near the semilocal limit of $\vartheta_S \approx \frac{\pi}{2}$, even when Higgs self-couplings are tuned to minimize instabilities. This suggests that such non-topological strings are unlikely to exist in unified theories based on ${\rm SU}(N>5)$ Lie algebras.

hep-ph↗

arXiv2024

Decay of geometry for a class of cubic polynomials

In this paper we study a class of bimodal cubic polynomials for which its critical points have the same $ω$-limit set which is an invariant Cantor set. These maps have generalized Fibonacci combinatorics in terms of generalized renormalization on the twin principal nest. It is proved that such maps possess `decay of geometry' in the sense that the scaling factor of the twin principal nest decreases at least exponentially fast. As an application, we prove that they have no Cantor attractor.

math.DS↗

arXiv2024

Lyapunov Exponent and Stochastic Stability for Infinitely Renormalizable Lorenz Maps

We prove that infinitely renormalizable contracting Lorenz maps with bounded geometry or the so-called {\it a priori bounds} satisfies the slow recurrence condition to the singular point $c$ at its two critical values $c_1^-$ and $c_1^+$. As the first application, we show that the pointwise Lyapunov exponent at $c_1^-$ and $c_1^+$ equals 0. As the second application, we show that such maps are stochastically stable.

math.DS↗