Yuriy Mishchenko

General theory of quantum field mixing

We present a general theory of mixing for an arbitrary number of fields with integer or half-integer spin. The time dynamics of the interacting fields is solved and the Fock space for interacting fields is explicitly constructed. The unitary inequivalence of the Fock space of base ~unmixed! eigenstates and the physical mixed eigenstates is shown by a straightforward algebraic method for any number of flavors in boson or fermion statistics. The oscillation formulas based on the nonperturbative vacuum are derived in a unified general formulation and then applied to both two- and three-flavor cases. Especially, the mixing of spin-1 ~vector! mesons and the Cabibbo-Kobayashi-Maskawa mixing phenomena in the standard model are discussed, emphasizing the nonperturbative vacuum effect in quantum field theory.

Phenomenology of flavor oscillations with non-perturbative effects from quantum field theory

We analyze phenomenological aspects of the quantum field theoretical formulation of meson mixing and obtain the exact oscillation formula in the presence of the decay. This formula is different from quantum mechanical formula by additional high-frequency oscillation terms. In the infinite volume limit, the space of the flavor quantum states is unitarily inequivalent to the space of energy eigenstates.

Higher Fock State Contributions to the Generalized Parton Distribution of Pion

We discuss the higher Fock-state (qqg) contributions to the nonzero value of the pion generalized parton distribution (GPD) at the crossover point x={zeta} between the DGLAP and ERBL regions. Using the phenomenological light-front constituent quark model, we confirm that the higher Fock-state contributions indeed give a nonzero value of the GPD at the crossover point. Iterating the light-front quark model wave function of the lowest qq Fock state with the Bethe-Salpeter kernel corresponding to the one-gluon exchange, we include all possible time-ordered qqg Fock-state contributions and obtain the pion GPD satisfying necessary sum rules and continuity conditions.

A NOVEL VARIATIONAL APPROACH FOR QUANTUM FIELD THEORY: EXAMPLE OF STUDY OF THE GROUND STATE AND PHASE TRANSITION IN NONLINEAR SIGMA MODEL

We discuss a novel form of the variational approach in Quantum Field Theory in which the trial quantum configuration is represented directly in terms of relevant expectation values rather than, e.g., increasingly complicated structure from Fock space. The quantum algebra imposes constraints on such expectation values so that the variational problem is formulated here as an optimization under constraints. As an example of application of such approach we consider the study of ground state and critical properties in a variant of nonlinear sigma model.

Molar mass estimate of dark matter from the dark mass distribution measurements

We study the distribution of dark matter versus visible matter using a set of data obtained from strong gravitational lensing in the galaxy cluster

Detecting the attention state of an operator in continuous attention task using EEG-based brain-computer interface

\mathrm{CL}0024+1654

Time-to-space conversion in quantum field theory of flavor mixing

and another set of data inferred from the universal rotation curves in spiral galaxies. The important feature of these two dramatically different observations is that the mass density profile of both visible and dark components can be estimated. From these measurements we deduce the mass of the dark matter particle and our estimate of the mass for the dark matter particle is

A large electroencephalographic motor imagery dataset for electroencephalographic brain computer interfaces

{\ensuremath{\mu}}_{d}\ensuremath{\approx}200\char21{}700\mathrm{MeV}.

Developing a 3- to 6-state EEG-based brain-computer interface for a robotic manipulator control

We contrast our estimates from

Dark matter phenomenology of high speed galaxy cluster collisions

\mathrm{CL}0024+1654