Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Twisted-mass lattice QCD with mass non-degenerate quarks   The maximally twisted lattice QCD action of an $SU_f(2)$ doublet of mass
degenerate Wilson quarks gives rise to a real positive fermion determinant and
it is invariant under the product of standard parity times the change of sign
of the coefficient of the Wilson term. The existence of this spurionic symmetry
implies that O($a$) improvement is either automatic or achieved through simple
linear combinations of quantities taken with opposite external three-momenta.
We show that in the case of maximal twist all these nice results can be
extended to the more interesting case of a mass non-degenerate quark pair.

37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math