Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Canonical Lagrangian Approach To Three-Space General Relativity   We study the action for the three-space formalism of General Relativity,
better known as the BF\'O (Barbour--Foster--\'O Murchadha) action, which is a
square-root BSW (Baierlein--Sharp--Wheeler) action. In particular, we explore
the (pre)symplectic structure by pulling it back via a Legendre map to the
tangent bundle of the configuration space of this action. With it we attain the
canonical Lagrangian vector field which generates the gauge transformations
(3-diffeomorphisms) and the true physical evolution of the system. This vector
field encapsulates all the dynamics of the system. We also discuss briefly the
observables and perennials for this theory. We then present a symplectic
reduction of the constrained phase space.

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The categories of this paper are: eess
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The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
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The categories of this paper are: q-fin
3
The categories of this paper are: physics
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The categories of this paper are: bayes-an
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The categories of this paper are: patt-sol
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The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
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The categories of this paper are: supr-con
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The categories of this paper are: econ
15
The categories of this paper are: nucl-ex