arXiv subjects

Leonid Lantsman

Publications and source records attributed to Leonid Lantsman.

10 recordsLinked to original sources

arXiv2025

Topological Theory of Helium 4

In this paper we attempt to construct the topological theory of superfluid helium $4$ in the framework of the (rigid) $U(1)$ model in which the initial $U(1)$ group is destroyed with appearance of (topologically nontrivial) domains separated by domain walls treated as step voltages between domains (e.g. with neighboring topological numbers). This can explain the superfluid properties in a helium $4$ specimen as well as the appearance of topologically nontrivial vortices therein.

cond-mat.supr-con↗

arXiv2021

BPS ansatzes as electric form-factors

We argue that BPS ansatzes, entering manifestly vacuum BPS monopole solutions to equations of motion in the (Minkowskian) non-Abelian Higgs model play the role of some electric form-factors and that this implies (soft) violating the CP-invariance of the mentioned model, similar to taking place in the Euclidian Yang-Mills (YM) theory with instantons, generating the $θ$-term in the appropriate effective Hamiltonian.

hep-th↗

arXiv2021

Whether the vacuum manifold in the Minkowskian non-Abelian model quantized by Dirac can be described with the aid of the superselection rules?

We intend to show that the vacuum manifold inherent in the Minkowskian non-Abelian model involving Higgs and Yang-Mills BPS vacuum modes and herewith quantized by Dirac can be described with the help of the superselection rules if and only if the "discrete" geometry for this vacuum manifold is assumed (it is just a necessary thing in order justify the Dirac fundamental quantization scheme applied to the mentioned model) and only in the infinitely narrow spatial region of the cylindrical shape where topologically nontrivial vortices are located inside this discrete vacuum manifold.

physics.gen-ph↗

arXiv2016

Topological Dirac variables in Abelian $U(1)$ theory

In this study we, remembering the experience with topological Dirac variables in the non-Abelian Yang-Mills-Higgs (YMH) model with vacuuum BPS monopole solutions, attempt to construct similar for the Abelian $U(1)$ model. We show that QED, as one understands it commonly, is only the topologically trivial sector ($n=0$) of this Abelian $U(1)$ model. For $n\neq 0$ one gets Dirac monopole modes. In both the cases, $n=0$ and $n\neq 0$, the theory can be quantized via the Hamiltonian reduction in terms of Dirac variables.

hep-th↗

arXiv2015

Superfluidity of Minkowskian Higgs vacuum with BPS monopoles quantized by Dirac may be described as Cauchy problem to Gribov ambiguity equation

We show that manifest superfluid properties of the Minkowskian Higgs model with vacuum BPS monopoles quantized by Dirac may be described in the framework of the Cauchy problem to the Gribov ambiguity equation. The latter equation specifies the ambiguity in choosing the covariant Coulomb (transverse) gauge for Yang-Mills fields represented as topological Dirac variables, may be treated as solutions to the Gauss law constraint at the removal of temporal components of these fields. We demonstrate that the above Cauchy problem comes just to fixing the covariant Coulomb gauge for topological Dirac variables in the given initial time instant $t_0$ and finding the solutions to the Gribov ambiguity equation in the shape of vacuum BPS monopoles and excitations over the BPS monopole vacuum referring to the class of multipoles. The next goal of the present study will be specifying the look of Gribov topological multipliers entering Dirac variables in the Minkowskian Higgs model quantized by Dirac, especially at the spatial infinity, $| {\bf x} | \to \infty$ (that corresponds to the infrared region of the momentum space).

hep-th↗

arXiv2009

Dirac fundamental quantization of gauge theories is natural way of reference frames in modern physics

We analyse two principal approaches to the quantization of physical models worked out to date. There are the Faddeev-Popov "heuristic" approach, based on fixing a gauge in the FP path integrals formalism, and the "fundamental" approach by Dirac based on the constraint-shell reduction of Hamiltonians with deleting unphysical variables. The relativistic invariant FP "heuristic" approach deals with the enough small class of problems associated with S-matrices squared taking on-shell of quantum fields. On the other hand, the "fundamental" quantization approach by Dirac involves the manifest relativistic covariance of quantum fields survived the constraint-shell reduction of Hamiltonians. This allows to apply this approach for the more broad class of problems than studying S-matrices. Researches about various bound states in QED and QCD are patterns of such applications. In the present study, with the example of the Dirac "fundamental" quantization of the Minkowskian non-Abelian Higgs model (us studied in its historical retrospective), we make sure in obvious advantages of this quantization approach. The arguments in favour of the Dirac fundamental quantization of physical model as a way of Einstein and Galilei relativity in modern physic will be presented.

hep-th↗

arXiv2007

Fermions with spin 1/2 as global SO(3) vortices

In this paper we show that the nontrivial fundamental group $π_1 SO(3) ={\Bbb Z}_2$ for the group SO(3) of global proper rotations of a four-dimensional Euclidian space (when a spin structure is introduced preliminarily in that space) implies always fermions as global SO(3) vortices, while bosons can be reduced to trivial lines (contracted into a point) in the SO(3) group space.

hep-th↗

arXiv2007

"Discrete" vacuum geometry as a tool for Dirac fundamental quantization of Minkowskian Higgs model

We demonstrate that assuming the "discrete" vacuum geometry in the Minkowskian Higgs model with vacuum BPS monopole solutions can justify the Dirac fundamental quantization of that model. The important constituent of this quantization is getting various rotary effects, including collective solid rotations inside the physical BPS monopole vacuum, and just assuming the "discrete" vacuum geometry seems to be that thing able to justify these rotary effects. More precisely, assuming the "discrete" geometry for the appropriate vacuum manifold implies the presence of thread topological defects (side by side with point hedgehog topological defects and walls between different topological domains) inside this manifold in the shape of specific (rectilinear) threads: gauge and Higgs fields located in the spatial region intimately near the axis $z$ of the chosen (rest) reference frame. This serves as the source of collective solid rotations proceeding inside the BPS monopole vacuum suffered the Dirac fundamental quantization. It will be argued that indeed the first-order phase transition occurs in the Minkowskian Higgs model with vacuum BPS monopoles quantized by Dirac. This comes to the coexistence of two thermodynamic phases inside the appropriate BPS monopole vacuum. There are the thermodynamic phases of collective solid rotations and superfluid potential motions.

hep-th↗

arXiv2006

Superfluid properties of BPS monopoles

This paper is devoted to demonstrating manifest superfluid properties of the Minkowskian Higgs model with vacuum BPS monopole solutions at assuming the "continuous" $\sim S^2$ vacuum geometry in that model. It will be also argued that point hedgehog topological defects are present in the Minkowskian Higgs model with BPS monopoles. It turns out, and we show this, that the enumerated phenomena are compatible with the Faddeev-Popov "heuristic" quantization of the Minkowskian Higgs model with vacuum BPS monopoles, coming to fixing the Weyl (temporal) gauge $A_0=0$ for gauge fields $A$ in the Faddeev-Popov path integral.

hep-th↗

arXiv2004

Minkowskian Yang-Mills vacuum

The well-known Bogomol'nyi-Prasad-Sommerfeld (BPS) monopole is considered in the limit of the infinite mass of the Higgs field as a basis for constructing the Yang-Mills vacuum with the finite energy density. In this limit the Higgs field disappears at the spatial infinity, but it leaves, nevertheless, its trace as vacuum Yang-Mills BPS monopoles transformed into Wu-Yang monopoles obtained in the pure Yang-Mills theory by a spontaneous scale symmetry breaking in the class of functions with zero topological charges. The topological degeneration of a vacuum BPS monopole manifests itself via Gribov copies of the covariant Coulomb gauge in the form of the time integral of the Gauss law constraint. We also show that, in the considered theory, there is a zero mode of the Gauss constraint involving an "electric" monopole and the additional mass of the $η'$-meson in Minkowskian QCD. The consequences of the Minkowskian physical monopole vacuum: rising "golden section" potential and topological confinement, are studied in the framework of the perturbation theory. An estimation of the vacuum expectation value of the square of the magnetic tension is given through the $η'$-meson mass, and arguments in favour of the stability of the monopole vacuum are considered. We also discuss why all these "smiles" of the Cheshire cat are kept by the Dirac fundamental quantization, but not by the conventional Faddeev-Popov integral.

math-ph↗