Do you want to publish a course? Click here

An improved lower bound for the critical parameter of the Stavskayas process

64   0   0.0 ( 0 )
 Publication date 2020
  fields
and research's language is English




Ask ChatGPT about the research

We consider the Stavskayas process, which is a two-states Probabilistic Celular Automata defined on a one-dimensional lattice. The process is defined in such a way that the state of any vertex depends only on itself and on the state of its right-adjacent neighbor. This process was one of the first multicomponent systems with local interaction, for which has been proved rigorously the existence of a kind of phase transition. However, the exact localization of its critical value remains as an open problem. In this work we provide a new lower bound for the critical value. The last one was obtained by Andrei Toom, fifty years ago.



rate research

Read More

87 - Xiaofeng Xue 2018
In this paper we give an improved upper bound for critical value $lambda_c$ of the basic contact process on the lattice $mathbb{Z}^d$ with $dgeq 3$. As a direct corollary of out result, [ lambda_cleq 0.384. ] when $d=3$.
56 - J. van den Berg , H. Don 2019
Consider critical site percolation on $mathbb{Z}^d$ with $d geq 2$. We prove a lower bound of order $n^{- d^2}$ for point-to-point connection probabilities, where $n$ is the distance between the points. Most of the work in our proof concerns a `construction which finally reduces the problem to a topological one. This is then solved by applying a topological fact, which follows from Brouwers fixed point theorem. Our bound improves the lower bound with exponent $2 d (d-1)$, used by Cerf in 2015 to obtain an upper bound for the so-called two-arm probabilities. Apart from being of interest in itself, our result gives a small improvement of the bound on the two-arm exponent found by Cerf.
207 - Yuansi Chen 2020
We prove an almost constant lower bound of the isoperimetric coefficient in the KLS conjecture. The lower bound has the dimension dependency $d^{-o_d(1)}$. When the dimension is large enough, our lower bound is tighter than the previous best bound which has the dimension dependency $d^{-1/4}$. Improving the current best lower bound of the isoperimetric coefficient in the KLS conjecture has many implications, including improvements of the current best bounds in Bourgains slicing conjecture and in the thin-shell conjecture, better concentration inequalities for Lipschitz functions of log-concave measures and better mixing time bounds for MCMC sampling algorithms on log-concave measures.
97 - Shui Feng , Wei Sun 2017
Let $alpha=1/2$, $theta>-1/2$, and $ u_0$ be a probability measure on a type space $S$. In this paper, we investigate the stochastic dynamic model for the two-parameter Dirichlet process $Pi_{alpha,theta, u_0}$. If $S=mathbb{N}$, we show that the bilinear form begin{eqnarray*} left{ begin{array}{l} {cal E}(F,G)=frac{1}{2}int_{{cal P}_1(mathbb{N})}langle abla F(mu), abla G(mu)rangle_{mu} Pi_{alpha,theta, u_0}(dmu), F,Gin {cal F}, {cal F}={F(mu)=f(mu(1),dots,mu(d)):fin C^{infty}(mathbb{R}^d), dge 1} end{array} right. end{eqnarray*} is closable on $L^2({cal P}_1(mathbb{N});Pi_{alpha,theta, u_0})$ and its closure $({cal E}, D({cal E}))$ is a quasi-regular Dirichlet form. Hence $({cal E}, D({cal E}))$ is associated with a diffusion process in ${cal P}_1(mathbb{N})$ which is time-reversible with the stationary distribution $Pi_{alpha,theta, u_0}$. If $S$ is a general locally compact, separable metric space, we discuss properties of the model begin{eqnarray*} left{ begin{array}{l} {cal E}(F,G)=frac{1}{2}int_{{cal P}_1(S)}langle abla F(mu), abla G(mu)rangle_{mu} Pi_{alpha,theta, u_0}(dmu), F,Gin {cal F}, {cal F}={F(mu)=f(langle phi_1,murangle,dots,langle phi_d,murangle): phi_iin B_b(S),1le ile d,fin C^{infty}(mathbb{R}^d),dge 1}. end{array} right. end{eqnarray*} In particular, we prove the Mosco convergence of its projection forms.
98 - Will Sawin 2021
The multicolor Ramsey number problem asks, for each pair of natural numbers $ell$ and $t$, for the largest $ell$-coloring of a complete graph with no monochromatic clique of size $t$. Recent works of Conlon-Ferber and Wigderson have improved the longstanding lower bound for this problem. We make a further improvement by replacing an explicit graph appearing in their constructions by a random graph. Graphs useful for this construction are exactly those relevant for a problem of ErdH{o}s on graphs with no large cliques and few large independent sets. We also make some basic observations about this problem.
comments
Fetching comments Fetching comments
Sign in to be able to follow your search criteria
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا