433 research outputs found
Metal Films as Mass Standard Samples in the Nano-Gram Range
Attestation of magnetron sputtered films as mass standards is presented. Homogeneous, long-lived
metal films were measured by different methods for comparison. The accuracy of the order 1 ng was found
to be provided by application of the metal film standards for element analysis by X-ray fluorescent method.
Keywords: Thin Films, Nano-Standards, Magnetron Sputtering, X-ray Reflectometry, X-ray Fluorescent
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3516
Interrelation of Information and Knowledge in the Economy of the Post-Industrial Society
Relevance of the study is to consider that in the post-industrial society the role of information and knowledge is so increased that they begin to occupy a decisive place in the production development. The purpose of the work is investigated interrelation of information and knowledge in the process of intellectual activity, which is a component of the production activity of the post-industrial production. The study task is to examine the role of information and knowledge in the formation of the new economy replacing the industrial one. In this paper used abstract-logical method historical method systemic and dialectical methods of analysis and synthesis. As a result of the research were justified "information" and "knowledge" as independent and interrelated categories; identifying peculiarities of knowledge that distinguish it from traditional production factors; studying intellectual activity as a component of the production activity
Supersymmetric null-surfaces
Single trace operators with the large R-charge in supersymmetric Yang-Mills
theory correspond to the null-surfaces in . We argue that the
moduli space of the null-surfaces is the space of contours in the
super-Grassmanian parametrizing the complex -dimensional subspaces of
the complex -dimensional space. The odd coordinates on this
super-Grassmanian correspond to the fermionic degrees of freedom of the
superstring.Comment: v4: added a reference to the earlier work; corrected the formula for
the stabilizer of the BMN vacuum; added the discussion of the complex
structure of the odd coordinates in Section 3.
Spiky strings and single trace operators in gauge theories
We consider single trace operators of the form O_{m_1 ... m_n} = tr D_+^{m_1}
F ... D_+^{m_n} F which are common to all gauge theories. We argue that, when
all m_i are equal and large, they have a dual description as strings with
cusps, or spikes, one for each field F. In the case of N=4 SYM, we compute the
energy as a function of angular momentum by finding the corresponding solutions
in AdS_5 and compare with a 1-loop calculation of the anomalous dimension. As
in the case of two spikes (twist two operators), there is agreement in the
functional form but not in the coupling constant dependence. After that, we
analyze the system in more detail and find an effective classical mechanics
describing the motion of the spikes. In the appropriate limit, it is the same
(up to the coupling constant dependence) as the coherent state description of
linear combinations of the operators O_{m_1 ... m_n} such that all m_i are
equal on average. This agreement provides a map between the operators in the
boundary and the position of the spikes in the bulk. We further suggest that
moving the spikes in other directions should describe operators with
derivatives other than D_+ indicating that these ideas are quite generic and
should help in unraveling the string description of the large-N limit of gauge
theories.Comment: 23 pages, 5 figures. v2: References and comments adde
On the integrability of Wilson loops in AdS_5 x S^5: Some periodic ansatze
Wilson loops are calculated within the AdS/CFT correspondence by finding a
classical solution to the string equations of motion in AdS_5 x S^5 and
evaluating its action. An important fact is that this sigma-model used to
evaluate the Wilson loops is integrable, a feature that has gained relevance
through the study of spinning strings carrying large quantum numbers and
spin-chains. We apply the same techniques used to solve the equations for
spinning strings to find the minimal surfaces describing a wide class of Wilson
loops. We focus on different cases with periodic boundary conditions on the
AdS_5 and S^5 factors and find a rich array of solutions. We examine the
different phases that appear in the problem and comment on the applicability of
integrability to the general problem.Comment: LaTex, 49 pages, 8 figure
Towards NNLO Accuracy in the QCD Sum Rule for the Kaon Distribution Amplitude
We calculate the and gluon radiative
corrections to the QCD sum rule for the first Gegenbauer moment of the
kaon light-cone distribution amplitude. The NNL0 accuracy is achieved for the
perturbative term and quark-condensate contributions to the sum rule. A
complete factorization is implemented, removing logarithms of -quark mass
from the coefficients in the operator-product expansion. The sum rule with
radiative corrections yields a_1^K(1 \GeV)=0.10\pm 0.04.Comment: 14 pages, 2 figure
1/J corrections to semiclassical AdS/CFT states from quantum Landau-Lifshitz model
One way to relate semiclassical string states and dual gauge theory states is
to show the equivalence between their low-energy effective 2d actions. The
gauge theory effective action, which is represented by an effective
Landau-Lifshitz (LL) model, was previously found to match with the string
theory world-sheet action up to the first two orders in the effective parameter
, where is the `t Hooft coupling
and is the total -charge. Here we address the question if quantizing the
effective LL action reproduces the subleading 1/J corrections to the spin chain
energies as well as the quantum corrections to the string energies. We
demonstrate that this is indeed the case provided one chooses an appropriate
regularization of the effective LL theory. Expanding near the BPS vacuum, we
show that the quantum LL action gives the same 1/J corrections to energies of
BMN states as found previously on the gauge theory and string theory sides. We
also compute the subleading corrections and show that these too match
with corrections computed from the Bethe ansatz. We also compare the results
from the LL action with a more direct computation from the spin chain. We
repeat the same computation for the -deformed LL action and find that
the quantum LL result is again equal to the 1/J correction computed from the
-deformed Bethe ansatz equations. We also quantize the LL action near
the rotating circular and folded string solutions, generalizing the known
gauge/string results for 1/J corrections to the classical energies. We
emphasize the simplicity of this effective field theory approach as compared to
the full quantum string computations.Comment: 52 pages, references adde
Large spin limits of AdS/CFT and generalized Landau-Lifshitz equations
We consider AdS_5 x S^5 string states with several large angular momenta along AdS_5 and S^5 directions which are dual to single-trace Super-Yang-Mills (SYM) operators built out of chiral combinations of scalars and covariant derivatives. In particular, we focus on the SU(3) sector (with three spins in S^5) and the SL(2) sector (with one spin in AdS_5 and one in S^5), generalizing recent work hep-th/0311203 and hep-th/0403120 on the SU(2) sector with two spins in S^5. We show that, in the large spin limit and at the leading order in the effective coupling expansion, the string sigma model equations of motion reduce to matrix Landau-Lifshitz equations. We then demonstrate that the coherent-state expectation value of the one-loop SYM dilatation operator restricted to the corresponding sector of single trace operators is also effectively described by the same equations. This implies a universal leading order equivalence between string energies and SYM anomalous dimensions, as well as a matching of integrable structures. We also discuss the more general 5-spin sector and comment on SO(6) states dual to non-chiral scalar operators
Circular and Folded Multi-Spin Strings in Spin Chain Sigma Models
From the SU(2) spin chain sigma model at the one-loop and two-loop orders we
recover the classical circular string solution with two S^5 spins (J_1, J_2) in
the AdS_5 x S^5 string theory. In the SL(2) sector of the one-loop spin chain
sigma model we explicitly construct a solution which corresponds to the folded
string solution with one AdS_5 spin S and one S^5 spin J. In the one-loop
general sigma model we demonstrate that there exists a solution which
reproduces the energy of the circular constant-radii string solution with three
spins (S_1, S_2, J).Comment: 16 pages, LaTeX, no figure
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