arXiv subjects

E. W. Lytvynov

Publications and source records attributed to E. W. Lytvynov.

3 recordsLinked to original sources

arXiv2007

Diffusion approximation for equilibrium Kawasaki dynamics in continuum

A Kawasaki dynamics in continuum is a dynamics of an infinite system of interacting particles in $\mathbb R^d$ which randomly hop over the space. In this paper, we deal with an equilibrium Kawasaki dynamics which has a Gibbs measure $μ$ as invariant measure. We study a diffusive limit of such a dynamics, derived through a scaling of both the jump rate and time. Under weak assumptions on the potential of pair interaction, $ϕ$, (in particular, admitting a singularity of $ϕ$ at zero), we prove that, on a set of smooth local functions, the generator of the scaled dynamics converges to the generator of the gradient stochastic dynamics. If the set on which the generators converge is a core for the diffusion generator, the latter result implies the weak convergence of finite-dimensional distributions of the corresponding equilibrium processes. In particular, if the potential $ϕ$ is from $C_{\mathrm b}^3(\mathbb R^d)$ and sufficiently quickly converges to zero at infinity, we conclude the convergence of the processes from a result in [Choi {\it et al.}, J. Math. Phys. 39 (1998) 6509--6536].

math.PR↗

arXiv2006

Analysis and geometry on marked configuration spaces

We carry out analysis and geometry on a marked configuration space $Ω^M_X$ over a Riemannian manifold $X$ with marks from a space $M$. We suppose that $M$ is a homogeneous space $M$ of a Lie group $G$. As a transformation group $\frak A$ on $Ω_X^M$ we take the ``lifting'' to $Ω_X^M$ of the action on $X\times M$ of the semidirect product of the group $\operatorname{Diff}_0(X)$ of diffeomorphisms on $X$ with compact support and the group $G^X$ of smooth currents, i.e., all $C^\infty$ mappings of $X$ into $G$ which are equal to the identity element outside of a compact set. The marked Poisson measure $π_σ$ on $Ω_X^M$ with Lévy measure $σ$ on $X\times M$ is proven to be quasiinvariant under the action of $\frak A$. Then, we derive a geometry on $Ω_X^M$ by a natural ``lifting'' of the corresponding geometry on $X\times M$. In particular, we construct a gradient $\nabla^Ω$ and a divergence $\operatorname{div}^Ω$. The associated volume elements, i.e., all probability measures $μ$ on $Ω_X^M$ with respect to which $\nabla^Ω$ and $\operatorname{div}^Ω$ become dual operators on $L^2(Ω_X^M;μ)$, are identified as the mixed marked Poisson measures with mean measure equal to a multiple of $σ$. As a direct consequence of our results, we obtain marked Poisson space representations of the group $\frak A$ and its Lie algebra $\frak a$. We investigate also Dirichlet forms and Dirichlet operators connected with (mixed) marked Poisson measures.

math.PR↗

arXiv2006

Analysis and geometry on $R_+$-marked configuration spaces

We carry out analysis and geometry on a marked configuration space $Ω_X^{R_+}$ over a Riemannian manifold $X$ with marks from the space $R_+$ as a natural generalization of the work {\bf [}{\it J. Func. Anal}. {\bf 154} (1998), 444--500{\bf ]}. As a transformation group $\mathfrak G$ on this space, we take the ``lifting'' to $Ω_X^{R_+}$ of the action on $X\times R_+$ of the semidirect product of the group Diff of diffeomorphisms on $X$ with compact support and the group $R_+^X$ of smooth currents, i.e., all $C^\infty$ mappings of $X$ into $R_+$ which are equal to one outside a compact set. The marked Poisson measure $π$ on $Ω_X^{R_+}$ with Lévy measure $σ$ is proven to be quasiinvariant under the action of $\mathfrak G$. Then, we derive a geometry on $Ω_X^{R_+}$ by a natural ``lifting'' of the corresponding geometry on $X\times R_+$. In particular, we construct a gradient $\nabla^Ω$ and divergence $div^Ω$. The associated volume elements, i.e., all probability measures $μ$ on $Ω_X^{R_+}$ with respect to which $\nabla^Ω$ and $div^Ω$ become dual operators on $L^2(Ω_X^{R_+} ,μ)$ are identified as the mixed Poisson measures with mean measure equal to a multiple of $σ$. As a direct consequence of our results, we obtain marked Poisson space representations of the group $\mathfrak G$ and its Lie algebra $\mathfrak g$. We investigate also Dirichlet forms and Dirichlet operators connected with (mixed) marked Poisson measures. In particular, we obtain conditions of ergodicity of the semigroups generated by the Dirichlet operators. A possible generalization of the results of the paper to the case where the marks belong to a homogeneous space of a Lie group is noted.

math.PR↗