1,432 research outputs found
Towards Integrability of Topological Strings I: Three-forms on Calabi-Yau manifolds
The precise relation between Kodaira-Spencer path integral and a particular
wave function in seven dimensional quadratic field theory is established. The
special properties of three-forms in 6d, as well as Hitchin's action
functional, play an important role. The latter defines a quantum field theory
similar to Polyakov's formulation of 2d gravity; the curious analogy with
world-sheet action of bosonic string is also pointed out.Comment: 31 page
Non-Linear Algebra and Bogolubov's Recursion
Numerous examples are given of application of Bogolubov's forest formula to
iterative solutions of various non-linear equations: one and the same formula
describes everything, from ordinary quadratic equation to renormalization in
quantum field theory.Comment: LaTex, 21 page
Reaction of diethyl vinylphosphonate with octyl- and dodecylamines
Diethyl vinylphosphonate reacted with octyl- and dodecylamines to give the corresponding addition products which underwent dealkylation via elimination of ethylene molecule with formation of crystalline zwitterionic ethyl 2-(alkylammonio)ethylphoshonates. © 2014 Pleiades Publishing, Ltd
A method development for improving the stability of vegetable polyphenol complexes for semi-finished minced meat products with antioxidant effect
Polyphenolic vegetable complexes are active antioxidants and play an important role in the processes of free radicals quenching in the human body. The aim of the work was to develop an immobilization method as a way for improving the stability of polyphenols in dried cowberry squeezing extract (DCSE) and to develop semi-finished minced meat products with antioxidant effect without changing their nutritional value. Experiments were carried out to study the nutritional value of DCSE. The presence of a large number of polyphenolic compounds in DCSE and a high radical-binding ability of the extract were revealed. Based on the mathematical planning method, an offal paste composition was obtained, which was used to obtain pellets, and the formulation of semi-finished minced meat products with pellets was optimized. It was established that preliminary immobilization of DCSE on offal pellets components allows to increase the level of total antioxidant content in the minced meat. Subsequent heat treatment of semi-finished minced meat products produced from such minced meat showed an increase in stability and, thus, bioavailability of antioxidants and the possibility of obtaining a finished product with antioxidant effect. The antioxidant effect of cowberry squeezing extract in the meat system is proved: accumulation of lipid oxidative decomposition products in the meat system during storage of frozen semi-finished minced meat products was inhibited to a greater extent when using offal pellets with immobilized compounds of cowberry squeezing extract. This work was carried out as part of the State Assignment of the Ministry of Education and Science of the Russian Federation No. 19.5486.2017/BCh and the «Young Scientists of ESSTU‑2019» grant
Sum Rules and Moments of the Nucleon Spin Structure Functions
The nucleon has been used as a laboratory to investigate its own spin
structure and Quantum Chromodynamics. New experimental data on nucleon spin
structure at low to intermediate momentum transfers combined with existing high
momentum transfer data offer a comprehensive picture of the transition region
from the {\it confinement} regime of the theory to its {\it asymptotic freedom}
regime. Insight for some aspects of the theory is gained by exploring lower
moments of spin structure functions and their corresponding sum rules (i.e. the
Gerasimov-Drell-Hearn, Bjorken and Burkhardt-Cottingham). These moments are
expressed in terms of an operator product expansion using quark and gluon
degrees of freedom at moderately large momentum transfers. The sum rules are
verified to a good accuracy assuming that no singular behavior of the structure
functions is present at very high excitation energies. The higher twist
contributions have been examined through the moments evolution as the moments
evolution as the momentum transfer varies from higher to lower values.
Furthermore, QCD-inspired low-energy effective theories, which explicitly
include chiral symmetry breaking, are tested at low momentum transfers. The
validity of these theories is further examined as the momentum transfer
increases to moderate values. It is found that chiral perturbation calculations
agree reasonably well with the first moment of the spin structure function
at momentum transfer of 0.1 GeV but fail to reproduce the neutron
data in the case of the generalized polarizability .Comment: 21 pages, 4 figures, review for Modern Physics Letters A. Minor
modifications in text and improved quality for one figure. Corrected mistakes
in section
Thermo-optic hysteresis with bound states in the continuum
We consider thermo-optic hysteresis in a silicon structure supporting bound
state in the continuum. Taking into account radiative heat transfer as a major
cooling mechanism we constructed a non-linear model describing the optical
response. It is shown that the thermo-optic hysteresis can be obtained with low
intensities of incident light at the red edge of the
visible under the critical coupling condition
Membranes for Topological M-Theory
We formulate a theory of topological membranes on manifolds with G_2
holonomy. The BRST charges of the theories are the superspace Killing vectors
(the generators of global supersymmetry) on the background with reduced
holonomy G_2. In the absence of spinning formulations of supermembranes, the
starting point is an N=2 target space supersymmetric membrane in seven
euclidean dimensions. The reduction of the holonomy group implies a twisting of
the rotations in the tangent bundle of the branes with ``R-symmetry'' rotations
in the normal bundle, in contrast to the ordinary spinning formulation of
topological strings, where twisting is performed with internal U(1) currents of
the N=(2,2) superconformal algebra. The double dimensional reduction on a
circle of the topological membrane gives the strings of the topological A-model
(a by-product of this reduction is a Green-Schwarz formulation of topological
strings). We conclude that the action is BRST-exact modulo topological terms
and fermionic equations of motion. We discuss the role of topological membranes
in topological M-theory and the relation of our work to recent work by Hitchin
and by Dijkgraaf et al.Comment: 22 pp, plain tex. v2: refs. adde
M-Theory of Matrix Models
Small M-theories unify various models of a given family in the same way as
the M-theory unifies a variety of superstring models. We consider this idea in
application to the family of eigenvalue matrix models: their M-theory unifies
various branches of Hermitean matrix model (including Dijkgraaf-Vafa partition
functions) with Kontsevich tau-function. Moreover, the corresponding duality
relations look like direct analogues of instanton and meron decompositions,
familiar from Yang-Mills theory.Comment: 12 pages, contribution to the Proceedings of the Workshop "Classical
and Quantum Integrable Systems", Protvino, Russia, January, 200
N D0-branes and antibranes in the background independent string field theory
In this paper we extend our previous work hep-th/0102063 to the case
D0-brane+antibrane system.Comment: 20 page
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