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2 votes
0 answers
83 views

Random time change and ergodicity

I guess it is a standard question in ergodic theory but I failed to find any reference to similar problems and I have no clue on how to tackle it. Let $(B_{t})_{t\in \mathbb{R}}$ be a standard ...
3 votes
2 answers
223 views

Measures with superexponential moments on finitely generated groups

Let $\Gamma$ be an infinite finitely generated group and let $\nu$ be a measure on $\Gamma$ which generates a transient random walk. I was reading this paper, and the authors prove many of their ...
20 votes
1 answer
2k views

Roadmap to Ergodic Theory

I have recently been interested in going deeper into ergodic theory, beyond an introductory level of knowledge. Background wise, my training has mostly been in stochastic analysis, and I have a ...
2 votes
1 answer
266 views

Ergodicity of linear dynamical systems and convergence of covariance matrices

Let $z(n+1)=Bz(n)+\xi(n+1)$ be an $N$-dimensional linear dynamical system with $\left(\xi(n)\right)_{n\in\mathbb{N}}$ being i.i.d. with $\xi(n)\sim\mathcal{N}(0,\Sigma_{\xi})$. Assumptions: a) The ...
2 votes
0 answers
313 views

Correlation decay rate

Let $T$ be a continuous transformation of a probability measure space $(X,\mathcal{B}(X),\mu)$ and $\varphi ,\phi \in L^2(\mu)$ (so-called observable) . The correlation function of $\varphi ,\phi$ (a ...
25 votes
6 answers
6k views

Proof of Krylov-Bogoliubov theorem

Where can I find a proof (in English) of the Krylov-Bogoliubov theorem, which states if $X$ is a compact metric space and $T\colon X \to X$ is continuous, then there is a $T$-invariant Borel ...
4 votes
1 answer
363 views

Maximal ergodic inequality

A map $f: X \to X$ preserves an ergodic probability $\mu$, i.e., $\mu \circ f^{-1}=\mu$ and for any $\phi: X \to \mathbb{R}$ with $\int \phi d\mu=0$, $$\frac{1}{n} \sum_{i \le n} \phi \circ f^i \to 0 \...
1 vote
1 answer
137 views

Ergodic theorem on limit of periodic transformations?

Suppose $(X,\mu)$ is a probability space, and $T_n, n \in \mathbb N$, is a sequence of periodic measure preserving transformations. For $x \in X$ and $f : X \to \mathbb R$, let $\mathrm{avg}_{f,n}(x)$...
3 votes
0 answers
153 views

Metropolis-Hastings sampling as a group action

Suppose that you have a topological space $\Omega \subset \mathbb R^n$ accompanied a measure $\mu$ and you're running an iterative sampling algorithm like Metropolis-Hastings. To sample you choose a ...
4 votes
0 answers
95 views

When the Jacobian of unstable measure converges

Let $T:X \to X$ be a hyperbolic map on the compact metric space $X$. Hyperbolicity means that $T$ has local stable and unstable sets with uniform exponential bounds, which satisfy a local product ...
5 votes
0 answers
183 views

Central limit theorem versus entropy in dynamical systems context

A dynamical system $(S^1,T, \mu)$, $T_* \mu=\mu$, $T$ ergodic, $S^1$ is circle. Assume it has central limit theorem. Want to know the relation between its measure-theoretic entropy $h_{\mu}(T)$ and ...
3 votes
0 answers
188 views

Invariant subspaces of Markov operators

I am currently working on some kind of graph theoretic problem and the following question came up: Suppose you have a Markov operator $T$ on $\ell^\infty$, that is a positive, bounded operator such ...
2 votes
0 answers
113 views

Characterizing the relationship between element-wise Markov transitions and the full-conditionals of the stationary distribution

Consider a $p$ dimensional random variable with a discrete support. Consider a Markov transition kernel on the state space that is defined in terms of element-wise transition distributions. One can ...
3 votes
0 answers
95 views

Empirically random, quickly multiplicable matrices

I have encountered a need for fast computation of a transformation $Ax$ where $A\in \mathbb{C}^{K\times N},\ K\sim 10^7,\ N\sim 10^3$ is designed, and $x\in \mathbb{C}^N$ has iid $\mathcal{CN}(0,1)$ ...
4 votes
2 answers
201 views

Uniform convergence of averages for stationary ergodic process

Let $\{X_t, t\in\mathbb R\}$ be a well-behaved$^*$ stationary ergodic process. I'm interested in the uniform convergence of averages: $$ \sup_{|x|\le R_n} \left|\frac1{2n}\int_{x-n}^{x+n} X_t dt - \...
2 votes
2 answers
242 views

iid random operator and its spectrum

consider an insteresting question: given Banach Space $ \mathcal{B}$, independent identical distribution random operator on $ \mathcal{B}$: $ (T_i)_{i \ge 1} $, where operator space is endowed with ...
1 vote
1 answer
404 views

Does Irreducibility holds for the Ergodic non-stationary Markov chain?

In the stationary case, I know that if the chain is irreducible and aperiodic, it is Ergodic. But in the non-stationary case, i can not comprehend the content deeply. I want to know if Irreducibility ...
1 vote
1 answer
193 views

Optimal joint coupling of all probability measures on a 3 point space

I am looking for any remotely related reference for the following problem, for which I have not the least clue what techniques would be useful. Consider a discrete probability space $\Omega = \{x, y, ...
5 votes
0 answers
143 views

Law of Large Numbers for the Tasep from a Bernoulli Configuration (Rost's Theorem)

Let $(\eta_{t}^{\rho})_{t\geq 0}$ be a totally asymmetric simple exclusion process (TASEP) from an initial configuration distributed according to the Bernoulli measure $\nu_{\rho}$ on $\{0,1\}^{\...
4 votes
1 answer
340 views

On the spectrum of stationary Gaussian process

What is the condition for ergodicity, weakly mixing, and strongly mixing properties of Gaussian process in terms of its spectrum? In a similar way let us consider a stationary vector valued Gaussian ...
10 votes
2 answers
2k views

Birkhoff Ergodic Theorem and Ergodic Decomposition Theorem for Continuous-Time Markov Processes

I have a couple of questions regarding ergodicity for Markov processes in continuous time. (In particular, the first question seems like it should be particularly basic, and yet I haven't managed to ...
21 votes
3 answers
1k views

Central Limit Theorem(s) for irrational rotation

Let $\alpha$ be irrational and $T: S^1 \rightarrow S^1$ be the rotation by $\alpha$. I'm interested in what type of Central Limit Theorem (if any) can hold for sums $Y_n = \frac{1}{\sqrt{n}}\sum_{k=1}^...
4 votes
0 answers
405 views

Reference request: stationary measures as convex combinations of ergodic measures

Does anyone know a good reference for the fact that a stationary probability measure is a convex combination of the stationary and ergodic probability measures? I have found some references for the ...
8 votes
3 answers
749 views

non-integrable subadditive ergodic theorem

Dear MO_World, I have (another) question about relaxing the assumptions in the sub-additive ergodic theorem. Apologies if this is something I should know already... There are a number of statements ...