Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The chiral phase transition for lattice QCD with 2 colour-sextet quarks   QCD with 2 flavours of massless colour-sextet quarks is studied as a possible
walking-Technicolor candidate. We simulate the lattice version of this model at
finite temperatures near to the chiral-symmetry restoration transition, to
determine whether it is indeed a walking theory (QCD-like with a running
coupling which evolves slowly over an appreciable range of length scales) or if
it has an infrared fixed point, making it a conformal field theory. The lattice
spacing at this transition is decreased towards zero by increasing the number
$N_t$ of lattice sites in the temporal direction. Our simulations are performed
at $N_t=4,6,8,12$, on lattices with spatial extent much larger than the
temporal extent. A range of small fermion masses is chosen to make predictions
for the chiral (zero mass) limit. We find that the bare lattice coupling does
decrease as the lattice spacing is decreased. However, it decreases more slowly
than would be predicted by asymptotic freedom. We discuss whether this means
that the coupling is approaching a finite value as lattice $N_t$ is increased
-- the conformal option, or if the apparent disagreement with the scaling
predicted by asymptotic freedom is because the lattice coupling is a poor
expansion parameter, and the theory walks. Currently, evidence favours QCD with
2 colour-sextet quarks being a conformal field theory. Other potential sources
of disagreement with the walking hypothesis are also discussed.
  We also report an estimate of the position of the deconfinement transition
for $N_t=12$, needed for choosing parameters for zero-temperature simulations.

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The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ