activity
20112025
most citedSeparatrix splitting at a Hamiltonian bifurcation

8 citations · 32 across the 13 of their papers we have counts for

collaborators

13 papers

math.DS2025

Double Hamiltonian Hopf Bifurcation: normalization and normal form non-integrability

L. M. Lerman, R. Mazrooei-Sebdani, N. E. Kulagin

The double Hamiltonian Hopf bifurcation is studied, i.e. a generic two-parametric unfolding of a smooth Hamiltonian system with four degrees of freedom which has at the critical va…

math.DS2022

Symplectic Partially Hyperbolic Automorphisms of 6-Torus

L. M. Lerman, K. N. Trifonov

We study topological properties of automorphisms of a 6-dimensional torus generated by integer matrices symplectic with respect to either the standard symplectic structure in six-d…

math.DS2021★ 1 cited

Non-autonomous vector fields on : simple dynamics and wild separatrices embedding

V. Z. Grines, L. M. Lerman

We construct new substantive examples of non-autonomous vector fields on 3-dimensional sphere having a simple dynamics but non-trivial topology. The construction is based on two id…

math.DS2020★ 3 cited

Saddle-center and periodic orbit: dynamics near symmetric heteroclinic connection

L. M. Lerman, K. N. Trifonov

An analytic reversible Hamiltonian system with two degrees of freedom is studied in a neighborhood of its symmetric heteroclinic connection made up of a symmetric saddle-center, a…

nlin.CD2020★ 4 cited

Solitons and cavitons in a nonlocal Whitham equation

N. Kulagin, L. Lerman, A. Malkin

Solitons and cavitons (localized solutions with singularities) for the nonlocal Whitham equations are studied. The equation of a fourth order with a parameter in front of fourth de…

math.DS2020

Geometry of symplectic partially hyperbolic automorphisms on 4-torus

L. M. Lerman, K. N. Trifonov

We study topological properties of automorphisms of 4-dimensional torus generated by integer symplectic matrices. The main classifying element is the structure of the topology of a…

math.AP2018

Abundance of entire solutions to nonlinear elliptic equations by the variational method

L. M. Lerman, P. E. Naryshkin, A. I. Nazarov

We study entire bounded solutions to the equation in . Our approach is purely variational and is based on concentration arguments and symmetry consi…

math.DS2018★ 5 cited

On interrelations between divergence-free and Hamiltonian dynamics

L. Lerman, E. Yakovlev

A mathematically correct description is presented on the interrelations between the dynamics of divergence free vector fields on an oriented 3-dimensional manifold and the dyna…

math.DS2018

Nonautonomous gradient-like ODEs on the circle: classification, structural stability and autonomization

L. M. Lerman, E. V. Gubina

We study a class of scalar differential equations on the circle . This class is characterized mainly by the property that any solution of such an equation possesses exponentia…

math.DS2015

Geometry of slow-fast Hamiltonian systems and Painlevé equations

L. M. Lerman, E. I. Yakovlev

In the first part of the paper we introduce some geometric tools needed to describe slow-fast Hamiltonian systems on smooth manifolds. We start with a smooth Poisson bundle $p: M\t…

nlin.CD2015★ 3 cited

Mixed Dynamics in a Parabolic Standard Map

L. M. Lerman, J. D. Meiss

We use numerical and analytical tools to demonstrate arguments in favor of the existence of a family of smooth, symplectic diffeomorphisms of the two-dimensional torus that have bo…

math.DS2014★ 8 cited

Separatrix splitting at a Hamiltonian bifurcation

Vassili Gelfreich, Lev Lerman

We discuss the splitting of a separatrix in a generic unfolding of a degenerate equilibrium in a Hamiltonian system with two degrees of freedom. We assume that the unperturbed fixe…

nlin.CD2011★ 8 cited

A saddle in a corner - a model of collinear triatomic chemical reactions

L. Lerman, V. Rom-Kedar

A geometrical model which captures the main ingredients governing atom-diatom collinear chemical reactions is proposed. This model is neither near-integrable nor hyperbolic, yet it…