80 research outputs found
Quantum corrections to dynamical holographic thermalization: entanglement entropy and other non-local observables
We investigate the thermalization time scale in the planar limit of the SU(N)
N=4 SYM plasma at strong yet finite 't Hooft coupling by considering its
supergravity dual description, including the full O(alpha'^3) type IIB string
theory corrections. We also discuss on the effects of the leading non-planar
corrections. We use extended geometric probes in the bulk which are dual to
different non-local observables in the N=4 SYM theory. This is carried out
within the framework of dynamical holographic thermalization.Comment: 19 pages, 4 figures. V2: References added, 1 figure added, 1 figure
corrected, enlarged discussions about extended probes, typos corrected.
Published versio
Deep inelastic scattering cross sections from the gauge/string duality
Differential cross sections of deep inelastic scattering of charged leptons
from hadrons are investigated by using the gauge/string duality. We consider
vector mesons derived from different holographic dual models obtaining a
general expression. We focus on the strongly coupled regime of dual gauge
theories for different values of the Bjorken parameter. We find new predictions
which are particularly interesting for differential scattering cross sections
of polarized leptons scattered off polarized vector mesons. We also carry out a
detailed comparison of the moments of the structure functions with lattice QCD
results.Comment: 42 pages, 5 tables, 9 figure
Deep inelastic scattering structure functions of holographic spin-1 hadrons with
Two-point current correlation functions of the large limit of
supersymmetric and non-supersymmetric Yang-Mills theories at strong coupling
are investigated in terms of their string theory dual models with quenched
flavors. We consider non-Abelian global symmetry currents, which allow one to
investigate vector mesons with . From the correlation functions we
construct the deep inelastic scattering hadronic tensor of spin-one mesons,
obtaining the corresponding eight structure functions for polarized vector
mesons. We obtain several relations among the structure functions. Relations
among some of their moments are also derived. Aspects of the sub-leading
contributions in the and expansions are discussed. At leading
order we find a universal behavior of the hadronic structure functions.Comment: 48 pages, 8 figure
Towards 1/N corrections to deep inelastic scattering from the gauge/gravity duality
corrections to deep inelastic scattering (DIS) of charged leptons
from glueballs at strong coupling are investigated in the framework of the
gauge/gravity duality. The structure functions and (and also )
are studied at subleading order in the expansion, in terms of and
the Bjorken parameter . The relevant type IIB supergravity one-loop diagrams
(which correspond to DIS with two-hadron final states) are studied in detail,
while -loop diagrams (corresponding to DIS with -hadron final states)
are briefly discussed. The and dependence of the
structure functions is analyzed. Within this context two very different limits
are considered: one is the large limit and the other one is when the
virtual photon momentum transfer is much larger than the infrared confining
scale . These limits do not commute.Comment: 45 page
Warped Deformed Throats have Faster (Electroweak) Phase Transitions
We study the dynamics of the finite-temperature phase transition for warped
Randall-Sundrum(RS)-like throat models related to the Klebanov-Tseytlin
solution. We find that, for infrared branes stabilized near the tip of the
throat, the bounce action has a mild N^2 dependence, where N(y) \sim [M_5
L(y)]^{3/2} is the effective number of degrees of freedom of the holographic
dual QFT, and where L(y) is the local curvature radius, which decreases in the
infrared. In addition, the bounce action is not enhanced by large numbers.
These features allow the transition to successfully complete over a wider
parameter range than for Goldberger-Wise stabilized RS models. Due to the
increase of L(y) in the ultraviolet, the throat has a reliable gravitational
description even when the number of infrared degrees of freedom is small. We
also comment on aspects of the thermal phase transition in Higgsless models,
where the gauge symmetry breaking is achieved via boundary conditions. Such
models include orbifold-GUT models and the Higgsless electroweak symmetry
breaking theories of Csaki et al., with Standard Model gauge fields living in
the bulk.Comment: published version, 18 pages, minor typo corrected, reference adde
Dynamics of holographic thermalization
Dynamical evolution of thin shells composed by different kinds of degrees of
freedom collapsing within asymptotically AdS spaces is explored with the aim of
investigating models of holographic thermalization of strongly coupled systems.
From the quantum field theory point of view this corresponds to considering
different thermal quenches. We carry out a general study of the thermalization
time scale using different parameters and space-time dimensions, by calculating
renormalized space-like geodesic lengths and rectangular minimal area surfaces
as extended probes of thermalization, which are dual to two-point functions and
rectangular Wilson loops. Different kinds of degrees of freedom in the shell
are described by their corresponding equations of state. We consider a scalar
field, as well as relativistic matter, a pressureless massive fluid and
conformal matter, which can be compared with the collapse of an AdS-Vaidya thin
shell. Remarkably, for conformal matter, the thermalization time scale becomes
much larger than the others. Furthermore, in each case we also investigate
models where the cosmological constants of the inner and outer regions
separated by the shell are different. We found that in this case only a scalar
field shell collapses, and that the thermalization time scale is also much
larger than the AdS-Vaidya case.Comment: 25 pages, 4 figures. V2: published versio
Hagedorn transition, vortices and D0 branes: Lessons from 2+1 confining strings
We study the behaviour of Polyakov confining string in the Georgi-Glashow
model in three dimensions near confining-deconfining phase transition described
in hep-th/0010201. In the string language, the transition mechanism is the
decay of the confining string into D0 branes (charged W bosons of the
Georgi-Glashow model). In the world-sheet picture the world-lines of heavy D0
branes at finite temperature are represented as world-sheet vortices of a
certain type, and the transition corresponds to the condensation of these
vortices. We also show that the ``would be'' Hagedorn transition in the
confining string (which is not realized in our model) corresponds to the
monopole binding transition in the field theoretical language. The fact that
the decay into D0 branes occurs at lower than the Hagedorn temperature is
understood as the consequence of the large thickness of the confining string
and finite mass of the branes.Comment: 31 pages, Late
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