Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Space-time uncertainty relation and Lorentz invariance   We discuss a Lorentz covariant space-time uncertainty relation, which agrees
with that of Karolyhazy-Ng-van Dam when an observational time period delta t is
larger than the Planck time lp. At delta t < lp, this uncertainty relation
takes roughly the form delta t delta x > lp^2, which can be derived from the
condition prohibiting the multi-production of probes to a geometry. We show
that there exists a minimal area rather than a minimal length in the
four-dimensional case. We study also a three-dimensional free field theory on a
non-commutative space-time realizing the uncertainty relation. We derive the
algebra among the coordinate and momentum operators and define a
positive-definite norm of the representation space. In four-dimensional
space-time, the Jacobi identity should be violated in the algebraic
representation of the uncertainty relation.

22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-th
1
The categories of this paper are: cs
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex