arXiv subjects
Publications and source records attributed to A. Yu. Ignatiev.
We examine the issue of magnetic charge quantization in the presence of black holes. It is pointed out that quantization of magnetic charge can lead to the mass quantization for magnetically charged black holes. We also discuss some implications for the experimental searches of magnetically charged black holes.
Hybrid $SU(2) \times U(1)$ models are the models in which $SU(2) \times U(1)$ symmetry is broken down not only spontaneously (as in the Standard Model), but also explicitely by adding a hard mass term for the U(1) field in the lagrangian. We study the issue of electric charge nonconservation and dequantization in these models. For this purpose we construct and analyze a series of hybrid models with different scalar contents. We show that some of these models posess an interesting property: the photon can remain massless (at least, at the tree level) even though the electric charge is not conserved.
We examine several issues related to the processes of Dirac monopole-antimonopole production in high-energy collisions such as $e^+e^-$ annihilation. Perturbative calculations for such processes are known to be inherently ambiguous due to the arbitrariness of direction of the monopole string; this requires use of some prescription to obtain physical results. We argue that different prescriptions lead to drastically different physical results which suggests that at present we do not have an entirely satisfactory procedure for the elimination of string arbitrariness (this problem is quite separate from the problems caused by the large coupling constant). We then analyze the consequencies of discrete symmetries (P and C) for the monopole production processes and for the monopole-antimonopole states. The P and C selection rules for the monopole-antimonopole states turn out to be different from those for the ordinary fermion-antifermion or boson-antiboson system. In particular, the spin 1/2 monopole and antimonopole should have the same helicities if they are produced through the one-photon annihilation of an electron and positron. A stronger selection rule holds for spinless monopoles: CP symmetry absolutely forbids the monopole-antimonopole production through the one-photon annihilation of an electron and positron. Single-photon $e^+e^- \to g^+g^-$ amplitude has been a key input in calculating the contribution of virtual $g^+g^-$ pairs to various physical processes such as the decay $Z\to 3γ$ and the anomalous magnetic moment of the electron. Applying our conclusions to these cases can lead to significant modifications of the results obtained in previous works.
We address the problem of string arbitrariness in the quantum field theory of Dirac magnetic monopoles. Different prescriptions are shown to yield different physical results. The constraints due to the discrete symmetries (C and P) are derived for the process of electron- positron annihilation into the monopole-antimonopole pair. In the case of the annihilation through the one-photon channel, the production of spin 0 monopoles is absolutely forbidden; spin 1/2 monopole and antimonopole should have the same helicities (or, equivalently, the monopole-antimonopole state should be p-wave $^1P_1$).
We study a novel type of extensions of the Standard Model which include a hard mass term for the U(1) gauge field and, optionally, the additional scalar multiplets spontaneously violating the electric charge conservation. Contrary to the case of abelian massive electrodynamics, in these theories the massiveness of photon necessarily implies non-conservation (and also dequantization) of the electric charge (even in the absence of spontaneous breakdown of the electromagnetic symmetry). On the other hand, unexpectedly, there exist models with charge non-conservation where it is possible to keep the photon mass zero (at least, at the tree level).
We investigate in detail the problem of constructing magnetic monopole solutions within the finite-range electrodynamics (i.e., electrodynamics with non-zero photon mass, which is the simplest extension of the standard theory; it is fully compatible with the experiment). We first analyze the classical electrodynamics with the additional terms describing the photon mass and the magnetic charge; then we look for a solution analogous to the Dirac monopole solution. Next, we plug the found solution into the Schrödinger equation describing the interaction between the the magnetic charge and the electron. After that, we try to derive the Dirac quantization condition for our case. Since gauge invariance is lost in massive electrodynamics, we use the method of angular momentum algebra. Under rather general assumptions we prove the theorem that the construction of such an algebra is not possible and therefore the quantization condition cannot be derived. This points to the conclusion that the Dirac monopole and the finite photon mass cannot coexist within one and the same theory. Some physical consequences of this conclusion are considered. The case of t'Hooft-Polyakov monopole is touched upon briefly.
We analyze the role played by the gauge invariance for the existence of Dirac monopole. To this end, we consider the electrodynamics with massive photon and ask if the magnetic charge can be introduced there. We show that the derivation of the Dirac quantization condition based on the angular momentum algebra cannot be generalized to the case of massive electrodynamics. Possible implications of this result are briefly discussed.
It has recently been shown that the neutrino can have non-zero electric charge in a number of gauge theories, including the Minimal Standard Model. Assuming non-zero neutrino charge, we develop a new approach to the solar neutrino problem. The key idea is that the charged neutrinos will be deflected by the Lorentz force while they are crossing the solar magnetic fields. Such a deflection will result in the anisotropy of the solar neutrino flux. Because of this anisotropy, the solar neutrino flux registered on earth can be reduced as compared to the Standard Solar Model prediction. The mechanism is purely classical and does not require neutrino oscillations, spin-flip or neutrino decay. We discuss qualitatively the consequences of our scenario for present and future solar neutrino experiments as well as differences between our mechanism and other proposed solutions.
We suggest that Bose statistics for photons can be tested by looking for decays of spin-1 bosons into two photons. The experimental upper limit on the decay $Z \rightarrow γγ$ is used to establish for the first time the quantitative measure of the validity of Bose symmetry for photons.
We have considered the effect of the reduction of the solar neutrino flux on earth due to the deflection of the charged neutrino by the magnetic field of the solar convective zone. The antisymmetry of this magnetic field about the plane of the solar equator induces the anisotropy of the solar neutrino flux thus creating the deficit of the neutrino flux on the earth. The deficit has been estimated in terms of solar and neutrino parameters and the condition of a 50 \% deficit has been obtained: $Q_ν gradH \agt 10^{-18} eG/cm$ where $Q_ν$ is the neutrino electric charge, $gradH$ is the gradient of the solar toroidal magnetic field, e is the electron charge. Some attractive experimental consequences of this scenario are qualitatively discussed.
We present the limits on possible time variation of the electric charges of quarks and leptons at the time of primordial nucleosynthesis within a model with dequantized electric charges which allows for the case of charged neutrino and neutron.