Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effective Theory Approach to the Spontaneous Breakdown of Lorentz
  Invariance   We generalize the coset construction of Callan, Coleman, Wess and Zumino to
theories in which the Lorentz group is spontaneously broken down to one of its
subgroups. This allows us to write down the most general low-energy effective
Lagrangian in which Lorentz invariance is non-linearly realized, and to explore
the consequences of broken Lorentz symmetry without having to make any
assumptions about the mechanism that triggers the breaking. We carry out the
construction both in flat space, in which the Lorentz group is a global
spacetime symmetry, and in a generally covariant theory, in which the Lorentz
group can be treated as a local internal symmetry. As an illustration of this
formalism, we construct the most general effective field theory in which the
rotation group remains unbroken, and show that the latter is just the
Einstein-aether theory.

12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
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The categories of this paper are: supr-con
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas