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We construct a new Yang-Mills 3D-solution on the space of negative scalar curvarure. We discuss a problem of non-abelian gauge symmetry is broken with the assumption that a scalar curvature of the domain is a negative small parameter. In this case we use the following fact: a geometrical scale related with Vassiliev's discriminant of magnetic lines coincids with a physical Kolmogorov scale. This gives an estimation of $\alpha$-effect by the dispersion of the asymptotic ergodic Hopf invariant in the limite with a negative scalar curvature parameter.

Desuspension Theorem for the steam $\Pi_{2^l-2}$ in stable homotopy groups of spheres is formulated and is proved. The proof is a minor revision of a theorem in the preprint \cite{A1} by the author (2010)., Comment: arXiv admin note: substantial text overlap with arXiv:1011.5717

We will give an elementary self-contained description of the Mahowald element in the stable homotopy group of spheres $\Pi_{2^l}$, $l \ge 3$. Using this construction, we prove that a generalized Kervaire Problem, formulated by the author in \cite{A} is solved positively.

The Kervaire Invariant 1 Problem until recently was an open problem in algebraic topology. Hill-Hopkins-Ravenel theorem clams a negative solution of the problem for all dimensions $n=2^l-2$, $l \ge 8$ \cite{H-H-R}. In dimension $n=126=2^7-2$, the problem is open, it is known as a hypothesis by V.P. Snaith (2009). We prove the statement of Hill-Hopkins-Ravenel theorem for all dimensions $2^l-2$, $l \ge l_0$, where $l_0$ is a sufficiently great positive integer. We prove that there is no element in $\Pi_{126}$ with Kervaire invariant one which is desuspended $9$ times into the homotopy group $\pi_{126+128-9}(S^{128-9})$. The proof is based on the Hirsh control principle and the compression Theorem. A notion internal symmetry: of Abelian (for skew-framed immersions), bi-cyclic (for $\mathbb{Z}/2^{[3]}$-framed immersions) and quaternion-cyclic structure (for $\mathbb{Z}/2^{[4]}$-framed immersions) are introduced.

The paper contains an example to describe magnetic fields in a conductive medium. The authors assume that new applications for turbulent magnetic fields in the case the magnetic field is not left- and right- polarized are possible.

Building on previous results on the quadratic helicity in magnetohydrodynamics (MHD) we investigate particular minimum helicity states. Those are eigenfunctions of the curl operator and are shown to constitute solutions of the quasi-stationary incompressible ideal MHD equations. We then show that these states have indeed minimum quadratic helicity., Comment: 13 pages, 2 figures

We discuss a generalisation of the Herbert formula for double points, when the normal bundle of an immersion admits an additional structure, and an application.

In this paper, we introduce geometric technique of working with skew-framed manifolds. It allows us to study stable homotopy groups of some Thom spaces by geometric means. We schematically describe how our results (which are also of independent interest) can be applied to obtain a proof of the Baum-Browder theorem stating non-immersibility of $\RP^{10}$ to $\R^{15}$.

For the quadratic helicity $\chi^{(2)}$ we present a generalization of the Arnol'd inequality which relates the magnetic energy to the quadratic helicity, which poses a lower bound. We then introduce the quadratic helicity density using the classical magnetic helicity density and its derivatives along magnetic field lines. For practical purposes we also compute the flow of the quadratic helicity and show that for an $\alpha^2$-dynamo setting it coincides with the flow of the square of the classical helicity. We then show how the quadratic helicity can be extended to obtain an invariant even under compressible deformations. Finally, we conclude with the numerical computation of $\chi^{(2)}$ which show cases the practical usage of this higher order topological invariant., Comment: 9 pages, 2 figures

The Kervaire Problem is an unsolved problem in Stable Homotopy Theory. The first interesting example is in dimension $30$. There exists a closed stably-parallelizable manifold $\tilde{M}^{30}$ with Arf-Kervaire invariant 1. It is unknown, if such a manifold exists in dimension $126$? The goal of the paper is to recall the construction of the manifold $M^{30}$ and investigate its properties.

An approach by J.Wu describes homotopy groups $\pi_{n}(S^2)$ of the standard 2-sphere as isotopy classes of spherical $n+1$--strand Brunnian braids is investigated in the case $n=3$ for applications.

Based on the model of the space $Pol_3(n)$ of polygons in $R^3$ with limited number of vertex, which was proposed by Jean-Claude Hausmann and Allen Knutson, and developed by several authors: Jason Cantarella, Alexander Y. Grosberg, Robert Kusner, and Clayton Shonkwiler, we prove that there exists an isometric isotopy of $Pol_3(n)$, $n=7$, into itself, which transforms an arbitrary polygon to its mirror copy, and, additionally, preserves lengths of projections of polygons into the two coordinate planes, and keeps projection of polygons onto the line. The proof is based on elementary arguments with Cayley numbers. A possible generalization of the statement for greater $n$ is related with a theorem by I.James on strong Kervaire invariants in stable homotopy of spheres.

Two non-local asymptotic invariants of magnetic fields for the ideal magnetohydrodynamics are introduced. The velocity of variation of the invariants for a non-ideal magnetohydrodynamics with a small magnetic dissipation is estimated. By means of the invariants the spectra of electromagnetic fields are investigated. A possible role of higher magnetic helicities during a relaxation of magnetic fields is discussed.

A solution of a problem by V.I.Arnol'd about higher analog of the asymptotic Hopf invariant of divergence-free vector fields is presented. A higher invariant of magnetic fields, which is not expressed from the asymptotic linking numbers of magnetic lines is constructed and examples of an asymptotic invariants is constructed.

A solution to the Kervaire invariant problem is presented. We introduce the concepts of abelian structure on skew-framed immersions, bicyclic structure on $\Z/2^{[3]}$--framed immersions, and quaternionic-cyclic structure on $\Z/2^{[4]}$--framed immersions. Using these concepts, we prove that for sufficiently large $n$, $n=2^{\ell}-2$, an arbitrary skew-framed immersion in Euclidean $n$-space $\R^n$ has zero Kervaire invariant. Additionally, for $\ell \ge 12$ (i.e., for $n \ge 4094$) an arbitrary skew-framed immersion in Euclidean $n$-space $\R^n$ has zero Kervaire invariant if this skew-framed immersion admits a compression of order 16.

Collection of (equivariant) $\rm{PL}$-mappings admitting a relative abelian, cyclic, quaternionic, bicyclic, and quaternionic-cyclic structures are constructed.

A geometric approach to the stable homotopy groups of spheres is developed in this paper, based on the Pontryagin-Thom construction. The task of this approach is to obtain an alternative proof of the Hill-Hopkins-Ravenel theorem [H-H-R] on Kervaire invariants in all dimensions, except, possibly, a finite number of dimensions. In the framework of this approach, the Adams theorem on the Hopf invariant is studied, for all dimensions with the exception of 15, 31, 63, 127. The new approach is based on the methods of geometric topology.

The dynamics of the magnetic helicity during the electroweak phase transition in the early Universe is studied. It is shown that the boundary surface between symmetric (hypermagnetic) phase and Maxwellian phase with a broken symmetry is a membrana for the separation of the magnetic helicity. Assuming the total linking number of knots of hypermagnetic field is negative, it is proved that the helicity rising in the Maxwellian phase is left-handed., Comment: 4 pages, no figures, extended version of published paper in Pis'ma ZHETF, 91 (2010)233

In this paper a geometric approach toward stable homotopy groups of spheres, based on the Pontrjagin-Thom construction is proposed. From this approach a new proof of Hopf Invariant One Theorem by J.F.Adams for all dimensions except $15,31,63,127$ is obtained. It is proved that for $n>127$ in the stable homotopy group of spheres $\Pi_n$ there is no elements with Hopf invariant one. The new proof is based on geometric topology methods. The Pontrjagin-Thom Theorem (in the form proposed by R.Wells) about the representation of stable homotopy groups of the real projective infinite-dimensional space (this groups is mapped onto 2-components of stable homotopy groups of spheres by the Khan-Priddy Theorem) by cobordism classes of immersions of codimension 1 of closed manifolds (generally speaking, non-orientable) is considered. The Hopf Invariant is expressed as a characteristic number of the dihedral group for the self-intersection manifold of an immersed codimension 1 manifold that represents the given element in the stable homotopy group. In the new proof the Geometric Control Principle (by M.Gromov) for immersions in a given regular homotopy classes based on Smale-Hirsch Immersion Theorem is required.

The notion of the geometrical $\Z/2 \oplus \Z/2$--control of self-intersection of a skew-framed immersion and the notion of the $\Z/2 \oplus \Z/4$-structure (the cyclic structure) on the self-intersection manifold of a $\D_4$-framed immersion are introduced. It is shown that a skew-framed immersion $f:M^{\frac{3n+q}{4}} \looparrowright \R^n$, $0 < q <

It is proved that there exists an integer $L$ such that a framed manifold of dimension $2^l-2$, $l\le L$ has the trivial Kervaire Invariant., Comment: 82pp. (In Russian)

We develop a geometric approach to stable homotopy groups of spheres in the spirit of the work of Pontrjagin and Rokhlin. A new proof of the Hopf Invariant One Theorem by J.F.Adams is obtained in all dimensions except 15 and 31. To prove that the stable Hopf invariant H: \Pi_n \to Z/2 vanishes for n>31, we apply methods of geometric topology. The Pontrjagin-Thom construction along with Hirsch's compression lemma identify every \alpha \in \Pi_n with the framed bordism class of a framed immersion of a closed n-manifold into R^{n+k}, for any given k>0. Its self-intersection M projects to an immersion f: M \to R^n which is framed by k copies of a line bundle \kappa. It is well-known that H(\alpha) = . The self-intersection N of f is framed by k copies of a plane bundle with structure group D_4. We observe that H(\alpha) = , where i immerses the double cover \bar N of N into M. The hardest part of the proof is to show that, after modifying f in its skew-framed bordism class, the classifying map g: N \to K(D_4,1) factors through K(Z/4,1), provided that n=2^l-1, l>5 and n-2k=15. This is achieved by analyzing immersions in the regular homotopy class of f that approximate the composition of the classifying map M \to RP^{n-k}, the projection of RP^{n-k} onto the join of copies of S^1/(Z/4) (the standard sphere), and an embedding of this join in R^n. The last step is proved with the quaternions., Comment: 99 pages, in Russian