163 research outputs found
Large Matrix Models and -Deformed Quantum Field Theories
Recently it was shown that an asymptotic behaviour of gauge theory
for large is described by q-deformed quantum field. The master fields for
large N theories satisfy to standard equations of relativistic field theory but
fields satisfy -deformed commutation relations with . These commutation
relations are realized in the Boltzmannian Fock space. The master field for
gauge theory does not take values in a finite-dimensional Lie algebra however
there is a non-Abelian gauge symmetry. The gauge master field for a subclass of
planar diagrams, so called half-planar diagrams, is also considered. A
recursive set of master fields summing up a matreoshka of 2-particles reducible
planar diagrams is briefly described.Comment: 17 pages, latex. To appear in "From Field Theory to Quantum Groups",
World Scientific. Proceedings to honor J.Lukierski in his 60th birthda
Shock waves in Lifshitz-like spacetimes
We construct shock waves for Lifshitz-like geometries in four- and
five-dimensional effective theories as well as in D3-D7 and D4-D6 brane
systems. The solutions to the domain wall profile equations are found. Further,
the study makes a connection with the implications for the quark-gluon plasma
formation in heavy-ion collisions. According to the holographic approach, the
multiplicity of particles produced in heavy-ion collisions can be estimated by
the area of the trapped surface formed in shock wave collisions. We calculate
the areas of trapped surfaces in the geometry of two colliding Lifshitz domain
walls. Our estimates show that for five-dimensional cases with certain values
of the critical exponent the dependence of multiplicity on the energy of
colliding ions is rather close to the experimental data observed at RHIC and LHC.Comment: 35 pages, 6 figures; v3: typos corrected. Version to appear in JHE
Holographic Non-equilibrium Heating
We study the holographic entanglement entropy evolution after a global sharp
quench of thermal state. After the quench, the system comes to equilibrium and
the temperature increases from to . Holographic dual of this process
is provided by an injection of a thin shell of matter in the black hole
background. The quantitative characteristics of the evolution depend
substantially on the size of the initial black hole. We show that
characteristic regimes during non-equilibrium heating do not depend on the
initial temperature and are the same as in thermalization. Namely these regimes
are pre-local-equilibration quadratic growth, linear growth and saturation
regimes of the time evolution of the holographic entanglement entropy. We study
the initial temperature dependence of quantitative characteristics of these
regimes and find that the critical exponents do not depend on the temperature,
meanwhile the prefactors are the functions on the temperature.Comment: v1:12 pages, 9 figures; v2:The title and abstract are slightly
changed, the discussion is enlarged, the pictures are changed to make
presentation more clear and refs. added , 22 pages, 4 figures; v3: typos
correcte
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