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Moving the needle on colorectal cancer genetics: it takes more than two to TANGO.
Interacting partially directed self avoiding walk. From phase transition to the geometry of the collapsed phase
In this paper, we investigate a model for a dimensional
self-interacting and partially directed self-avoiding walk, usually referred to
by the acronym IPDSAW. The interaction intensity and the free energy of the
system are denoted by and , respectively. The IPDSAW is known to
undergo a collapse transition at . We provide the precise asymptotic
of the free energy close to criticality, that is we show that
where is computed
explicitly and interpreted in terms of an associated continuous model. We also
establish some path properties of the random walk inside the collapsed phase
. We prove that the geometric conformation adopted by the
polymer is made of a succession of long vertical stretches that attract each
other to form a unique macroscopic bead, we identify the horizontal extension
of the random walk inside the collapsed phase and we establish the convergence
of the rescaled envelope of the macroscopic bead towards a deterministic Wulff
shape.Comment: Accepted for publication in the Annals of Probabilit
Deconfining transition in two-flavor QCD
The order and the nature of the finite-temperature phase transition of QCD
with two flavors of dynamical quarks is investigated. An analysis of the
critical exponent of the specific heat is performed through finite-size and
finite-mass scaling of various susceptibilities. Dual superconductivity of QCD
vacuum is investigated using a disorder parameter, namely the v.e.v. of a
monopole creation operator. Hybrid R simulations were run at lattice spatial
sizes of , , and and temporal size , with
quark masses in the range .Comment: Lattice2003(topology), 3 page
Color confinement and dual superconductivity in full QCD
We report on evidence that confinement is related to dual superconductivity
of the vacuum in full QCD, as in quenched QCD. The vacuum is a dual
superconductor in the confining phase, whilst the U(1) magnetic symmetry is
realized a la Wigner in the deconfined phase.Comment: 4 pages, 4 eps figure
Twin Peaks: A possible signal in the production of resonances beyond special relativity
It is usually expected that quantum gravity corrections will modify somehow
the symmetries of special relativity. In this paper we point out that the
possibility of very low-energy (with respect to the Planck energy)
modifications to special relativity in the framework of a deformed relativistic
theory is not ruled out, and that, depending on the value of that scale, such a
possibility could be tested in accelerator physics. In particular, we take a
simple example of a relativistic kinematics beyond special relativity from the
literature, and obtain a remarkable effect: two correlated peaks ("twin peaks")
associated to a single resonance. We analyze this phenomenology in detail, use
LEP data to put constraints of the order of TeV on the scale of corrections to
special relativity, and note that such an effect might be observable in a
future very high-energy proton collider.Comment: 17 pages, accepted for publication in Symmetr
Magnetic charge superselection in the deconfined phase of Yang-Mills theory
The vacuum expectation value of an operator carrying magnetic charge is
studied numerically for temperatures above the deconfinement temperature in
SU(2) and SU(3) gauge theory. By analyzing its finite size behaviour, this is
found to be exactly zero in the thermodynamical limit for any T > T_c whenever
the magnetic charge of the operator is different from zero. These results show
that magnetic charge is superselected in the hot phase of quenched QCD.Comment: 4 pages, 6 figures, revtex
Antiferromagnetic O(N) models in four dimensions
We study the antiferromagnetic O(N) model in the F_4 lattice. Monte Carlo
simulations are applied for investigating the behavior of the transition for
N=2,3. The numerical results show a first order nature but with a large
correlation length. The limit is also considered with analytical
methods.Comment: 14 pages, 3 postscript figure
Asymptotic approach to Special Relativity compatible with a relativistic principle
We propose a general framework to describe Planckian deviations from Special
Relativity (SR) compatible with a relativistic principle. They are introduced
as the leading corrections in an asymptotic approach to SR going beyond the
energy power expansion of effective field theories. We discuss the conditions
in which these Planckian effects might be experimentally observable in the near
future, together with the non-trivial limits of applicability of this
asymptotic approach that such a situation would produce, both at the very high
(ultraviolet) and the very low (infrared) energy regimes.Comment: 12 page
Color confinement and dual superconductivity in unquenched QCD
We report on evidence from lattice simulations that confinement is produced
by dual superconductivity of the vacuum in full QCD as in quenched QCD.
Preliminary information is obtained on the order of the deconfining phase
transition.Comment: 4 pages, to appear in the Proceedings of Quark Matter 02 - The XVI
International Conference on Ultrarelativistic Nucleus-Nucleus Collision
Chiral transition and deconfinement in N_f = 2 QCD
The transition is studied by means of a disorder parameter detecting
condensation of magnetic monopoles in the vacuum. The deconfining transition is
found to coincide with the chiral transition and the susceptibility \rho,
related to the disorder parameter, is consistent with a first order phase
transition.Comment: 3 pages, 2 figures. Poster presented at Lattice2004(topology),
Fermilab, June 21-26, 200
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