8,860 research outputs found
Relation between the chiral and deconfinement phase transitions
Lattice QCD simulations at finite temperature have shown that the chiral
phase transition in the chiral limit and the deconfinement phase transition in
the quenched limit are continuously connected. I emphasize the nontriviality of
this result and propose an unconventional scenario which naturally explains the
existing lattice data. The continuity of the two phase transitions is a
manifestation of the familiar glueball-meson mixing, which can be traced back
to the properties of QCD at zero temperature.Comment: 5 pages, talk given at Strong and Electroweak Matter 2004 (SEWM04),
Helsinki, Finland, 16-19 Jun 200
Separating hard and soft scales in hard processes in a QCD plasma
We present a picture of hard processes in a hot plasma in terms of the hard
scale part of the process, where perturbative QCD should be applicable, and the
soft scale part of the process, where we look to the AdS/CFT correspondence for
guidance to possible strong effective coupling phenomena. In particular we
estimate , the transport coefficient, supposing that at soft scales
partons in the plasma all cascade to small--values as indicated by strong
coupling SYM theory.Comment: 8 page
Deep Inelastic Scattering in Holographic AdS/QCD Models
We review the description of deep inelastic scattering using some AdS/QCD
phenomenological models.Comment: Talk presented by NRFB at Light Cone 2009: Relativistic Hadronic and
Particle Physics, 8-13 Jul 2009, Sao Jose dos Campos, Brazi
"A Theory of Commodity Tax Reform under Revenue Constraint"
Despite the development of the optimal taxation theory , few of the practicing tax economists question the traditional wisdom that making tax rates flat will lead to a more efficient tax system. Practicing tax economists seem to have an intuition that even if the uniform tax structure may not be the most efficient, it may be a close approximation. The present paper survey the literature that provides theoretical under-pinnings for the practitioner's intuition. Also, the paper simplifies the statements and proofs of theorems in literature.
Collinearly improved JIMWLK evolution in Langevin form
The high-energy evolution of Wilson line operators, which at leading order is
described by the Balitsky-JIMWLK equations, receives large radiative
corrections enhanced by single and double collinear logarithms at
next-to-leading order and beyond. We propose a method for resumming such
logarithmic corrections to all orders, at the level of the Langevin formulation
of the JIMWLK equation. The ensuing, collinearly-improved Langevin equation
features generalized Wilson line operators, which depend not only upon rapidity
(the logarithm of the longitudinal momentum), but also upon the transverse size
of the color neutral projectile to which the Wilson lines belong. This
additional scale dependence is built up during the evolution, via the condition
that the successive emissions of soft gluons be ordered in time. The presence
of this transverse scale in the Langevin equation furthermore allows for the
resummation of the one-loop running coupling corrections.Comment: 24 pages, 1 figur
Jet fragmentation and gauge/string duality
We consider an analog of e^+e^- annihilation in gauge theories which have a
dual string description in asymptotically AdS_5 space and discuss the nature of
jet fragmentation. We construct the timelike anomalous dimension which governs
the scale dependence of the fragmentation function. In the limit of infinite 't
Hooft coupling, the average multiplicity rises linearly with the energy and the
inclusive spectrum is peaked at the kinematical boundary.Comment: 9 pages, v2:comments and references adde
Proton number fluctuation as a signal of the QCD critical end-point
We argue that the event-by-event fluctuation of the proton number is a
meaningful and promising observable for the purpose of detecting the QCD
critical end-point in heavy-ion collision experiments. The long range
fluctuation of the order parameter induces a characteristic correlation between
protons which can be measured. The proton fluctuation also manifests itself as
anomalous enhancement of charge fluctuations near the end-point, which might be
already seen in existing data.Comment: 4 pages, version accepted in PR
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