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BMy. CepHH 3. OH3HKA. ACTPOHOMHfl. 2022. №2
THEORY
Creation of Neutral Fermions with Anomalous Magnetic Moment
from the Vacuum by Magnetic Steps
T.C. Adorno1'2'3'", Zi-Wang He1'2'6, S. P. Gavrilov3'4, D. M. Gitman3'5'6 E-mail: atg.adorno@gmail.com, 61248049347@qq.com
1 Department of Physics, College of Physical Sciences and Technology, Hebei University. Baoding, 071002, China 2Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province, Hebei
University. Baoding, China 3Department of Physics, Tomsk State University. Tomsk, 634050, Russia 4Department of General and Experimental Physics, Herzen State Pedagogical University of Russia
St. Petersburg, 191186, Russia 5P.N. Lebedev Physical Institute. Moscow, 119991, Russia 6Universidade de Sao Paulo, Caixa Postal 66318, CEP 05508-090, Sao Paulo, S.P., Brazil
Received January 15, 2022
We present recent results on neutral fermion pair production by magnetic field inhomogeneities as external backgrounds. Vacuum instability characteristics are calculated in the framework of QED with x-steps and specified to a magnetic step that allows solving the relativistic wave equation pertinent to this problem.
Keywords: quantum electrodynamics, Dirac-Pauli equation, nonperturbative effects.
English version: Moscow University Physics Bulletin. 2022. 77, No. 2. Pp. 434-438.
Neutrino Oscillations in Gravitational Fields and Astrophysical Applications
M. Dvornikov E-mail: maxdvo@izmiran.ru Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radiowave Propagation (IZMIRAN)
Moscow, 108840, Troitsk, Russia Received December 9, 2021
The neutrino propagation and oscillations in various gravitational fields are studied. First, we consider the neutrino scattering off a black hole accounting for the neutrino spin precession. Then, we study the evolution of flavor neutrinos in stochastic gravitational waves. The astrophysical applications of the obtained results are considered.
Keywords: neutrino, evolution of flavor neutrinos.
English version: Moscow University Physics Bulletin. 2022. 77, No. 2. Pp. 439-441.
Obtaining Fully Polarized Amplitudes in Gauge Invariant Form
N. Ahmadiniaz1'", V.M. Banda Guzman2'6, F. Bastianelli3'c, O. Corradini4, J.P. Edwards2, Ch. Schubert2 E-mail: ajpedwards@cantab.net, 6victor.banda@umich.mx, cbastianelli@bo.infn.it
1Helmholtz-Zentrum Dresden-Rossendorf, Dresden, 01328 Germany 2Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolas de Hidalgo, Morelia, México 3Dipartimento di Fisica e Astronomia «Augusto Righi», Universita di Bologna. Bologna, I-40126 Italy 4Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Universita degli Studi di Modena e Reggio. Italy
Received January 16, 2022
We describe progress applying the Worldline Formalism of quantum field theory to the fermion propagator dressed by N-photons to study multi-linear Compton scattering processes, explaining how this approach — whose calculational advantages are well-known at multi-loop order — yields compact and manifestly gauge invariant scattering amplitudes.
Keywords: quantum field theory, scattering amplitudes, worldline formalism.
English version: Moscow University Physics Bulletin. 2022. 77, No. 2. Pp. 442-445.