Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Glueball masses in 4d U(1) lattice gauge theory using the multi-level
  algorithm   We take a new look at plaquette-plaquette correlators in 4d compact U(1)
lattice gauge theory which are separated in time, both in the confined and the
deconfined phases. From the behaviour of these correlators we extract glueball
masses in the scalar as well as the axial-vector channels. Also in the
deconfined phase, the non-zero momentum axial-vector correlator gives us
information about the photon which appears as a massless particle in the
spectrum. Using the Luescher - Weisz multi-level algorithm, we are able to go
to large time separations which were not possible previously.

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The categories of this paper are: q-fin
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The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
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The categories of this paper are: eess
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con