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The role of language in the online evaluation of hospitality service encounters: an empirical study
In an increasingly global travel market, hospitality services encounters involve growing interactions between providers and customers often belonging to different nationalities and cultures and speaking different languages. Extant hospitality management literature has explored the influence of language on service evaluations mostly in offline settings. This study innovatively captures the effect of the language used in online hotel reviews on online consumer ratings in two distinctively different destinations located in culturally different countries: Italy and Russia. Based on almost half a million Booking.com online reviews written by hotel guests in Moscow and Rome, we illuminate if and to what extent domestic vs. foreign language use affects online customer satisfaction. We find that the use of domestic language exerts a positive impact on online ratings in both countries. Implications for hospitality practitioners and managers, developers and managers of online review platforms, and customers of hotel services are discussed
Generalization of the BLM procedure and its scales in any order of pQCD
The Brodsky--Lepage--Mackenzie procedure is sequentially and unambiguously
extended to any fixed order of perturbative QCD beyond the so called
``large--\beta_0 approximation''. As a result of this procedure, the obtained
perturbation series looks like a continued-fraction representation. A
subsequent generalization of this procedure is developed, in order to optimize
the convergence of the final series, along the lines of the Fastest Convergence
Prescription. This generalized BLM procedure is applied to the Adler D function
and also to R_{e^+e^-} in QCD at NLO. A further extension of the sequential
BLM is presented which makes use of additional parameters to optimize the
convergence of the power-series at any fixed order of expansion.Comment: 24 pages, JHEP3, 4 figures are enclosed as eps-file, final version to
be published in JHE
The Dressing Factor and Crossing Equations
We utilize the DHM integral representation for the BES dressing factor of the
world-sheet S-matrix of the AdS_5xS^5 light-cone string theory, and the
crossing equations to fix the principal branch of the dressing factor on the
rapidity torus. The results obtained are further used, in conjunction with the
fusion procedure, to determine the bound state dressing factor of the mirror
theory. We convincingly demonstrate that the mirror bound state S-matrix found
in this way does not depend on the internal structure of a bound state solution
employed in the fusion procedure. This welcome feature is in perfect parallel
to string theory, where the corresponding bound state S-matrix has no bearing
on bound state constituent particles as well. The mirror bound state S-matrix
we found provides the final missing piece in setting up the TBA equations for
the AdS_5xS^5 mirror theory.Comment: LaTex, 48 pages, 10 figures; v2: a new section added where the
dressing factor of the mirror theory is found; v3: formula (6.12) is
corrected, a new figure is added, accepted for publication in J.Phys.
On "Non-Geometric" Contribution To The Entropy Of Black Hole Due To Quantum Corrections
The quantum corrections to the entropy of charged black holes are calculated.
The Reissner-Nordstrem and dilaton black holes are considered. The appearance
of logarithmically divergent terms not proportional to the horizon area is
demonstrated. It is shown that the complete entropy which is sum of classical
Bekenstein-Hawking entropy and the quantum correction is proportional to the
area of quantum-corrected horizon.Comment: Latex, 9 page
Foundations of the AdS_5 x S^5 Superstring. Part I
We review the recent advances towards finding the spectrum of the AdS_5 x S^5
superstring. We thoroughly explain the theoretical techniques which should be
useful for the ultimate solution of the spectral problem. In certain cases our
exposition is original and cannot be found in the existing literature. The
present Part I deals with foundations of classical string theory in AdS_5 x
S^5, light-cone perturbative quantization and derivation of the exact
light-cone world-sheet scattering matrix.Comment: 161 page
Gauge-string duality for superconformal deformations of N=4 Super Yang-Mills theory
We analyze in detail the relation between an exactly marginal deformation of
N=4 SYM - the Leigh-Strassler or ``beta-deformation'' - and its string theory
dual (recently constructed in hep-th/0502086) by comparing energies of
semiclassical strings to anomalous dimensions of gauge-theory operators in the
two-scalar sector. We stress the existence of integrable structures on the two
sides of the duality. In particular, we argue that the integrability of strings
in AdS_5 x S^5 implies the integrability of the deformed world sheet theory
with real deformation parameter. We compare the fast string limit of the
worldsheet action in the sector with two angular momenta with the continuum
limit of the coherent state action of an anisotropic XXZ spin chain describing
the one-loop anomalous dimensions of the corresponding operators and find a
remarkable agreement for all values of the deformation parameter. We discuss
some of the properties of the Bethe Ansatz for this spin chain, solve the Bethe
equations for small number of excitations and comment on higher loop properties
of the dilatation operator. With the goal of going beyond the leading order in
the 't Hooft expansion we derive the analog of the Bethe equations on the
string-theory side, and show that they coincide with the thermodynamic limit of
the Bethe equations for the spin chain. We also compute the 1/J corrections to
the anomalous dimensions of operators with large R-charge (corresponding to
strings with angular momentum J) and match them to the 1-loop corrections to
the fast string energies. Our results suggest that the impressive agreement
between the gauge theory and semiclassical strings in AdS_5 x S^5 is part of a
larger picture underlying the gauge/gravity duality.Comment: 50 pages, Latex; v2:typos corrected, references added, clarifications
in sec 8 and Appendix A, a discussion of a rational solution added in section
4.2; v3: minor corrections to coefficients in eq. 2.5, 5.2 and appendix A;
v4: minor misprints correcte
Uniform Light-Cone Gauge for Strings in AdS_5 x S^5: Solving su(1|1) Sector
We introduce a uniform light-cone gauge for strings propagating in AdS
space-time. We use the gauge to analyze strings from the su(1|1) sector, and
show that the reduced model is described by a quadratic action for two complex
fermions. Thus, the uniform light-cone gauge allows us to solve the model
exactly. We analyze the near BMN spectrum of states from the su(1|1) sector and
show that it correctly reproduces the 1/J corrections. We also compute the
spectrum in the strong coupling limit, and derive the famous \lambda^{1/4}
asymptotics. We then show that the same string spectrum can be also derived by
solving Bethe ansatz type equations, and discuss their relation to the quantum
string Bethe ansatz for the su(1|1) sector.Comment: 26 pages, Latex, v2: comparison to the strong coupling expansion of
the quantum string Bethe ansatz is added, discussion of the winding sector is
extended, references adde
Konishi operator at intermediate coupling
TBA equations for two-particle states from the sl(2) sector proposed by
Arutyunov, Suzuki and the author are solved numerically for the Konishi
operator descendent up to 't Hooft's coupling lambda ~ 2046. The data obtained
is used to analyze the properties of Y-functions and address the issue of the
existence of the critical values of the coupling. In addition we find a new
integral representation for the BES dressing phase which substantially reduces
the computational time.Comment: lots of figures, v2: improved numerics, c1=2, c2=0, c4 does not
vanis
On String S-matrix, Bound States and TBA
The study of finite J effects for the light-cone AdS superstring by means of
the Thermodynamic Bethe Ansatz requires an understanding of a companion 2d
theory which we call the mirror model. It is obtained from the original string
model by the double Wick rotation. The S-matrices describing the scattering of
physical excitations in the string and mirror models are related to each other
by an analytic continuation. We show that the unitarity requirement for the
mirror S-matrix fixes the S-matrices of both theories essentially uniquely. The
resulting string S-matrix S(z_1,z_2) satisfies the generalized unitarity
condition and, up to a scalar factor, is a meromorphic function on the elliptic
curve associated to each variable z. The double Wick rotation is then
accomplished by shifting the variables z by quarter of the imaginary period of
the torus. We discuss the apparent bound states of the string and mirror
models, and show that depending on a choice of the physical region there are
one, two or 2^{M-1} solutions of the M-particle bound state equations sharing
the same conserved charges. For very large but finite values of J, most of
these solutions, however, exhibit various signs of pathological behavior. In
particular, they might receive a finite J correction to their energy which is
complex, or the energy correction might exceed corrections arising due to
finite J modifications of the Bethe equations thus making the asymptotic Bethe
ansatz inapplicable.Comment: 77 pages, 6 figures, v2: the statement about the periodicity
condition for mirror fermions corrected; typos corrected; references added,
v3: misprints correcte
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