Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum evolution in spacetime foam   In this work, I review some aspects concerning the evolution of quantum
low-energy fields in a foamlike spacetime, with involved topology at the Planck
scale but with a smooth metric structure at large length scales, as follows.
Quantum gravitational fluctuations may induce a minimum length thus introducing
an additional source of uncertainty in physics. The existence of this
resolution limit casts doubts on the metric structure of spacetime at the
Planck scale and opens a doorway to nontrivial topologies, which may dominate
Planck scale physics. This foamlike structure of spacetime may show up in
low-energy physics through loss of quantum coherence and mode-dependent energy
shifts, for instance, which might be observable. Spacetime foam introduces
nonlocal interactions that can be modeled by a quantum bath, and low-energy
fields evolve according to a master equation that displays such effects.
Similar laws are also obtained for quantum mechanical systems evolving
according to good real clocks, although the underlying Hamiltonian structure in
this case establishes serious differences among both scenarios. Contents.---
Quantum fluctuations of the gravitational field; Spacetime foam; Loss of
quantum coherence; Quantum bath; Low-energy effective evolution; Real clocks;
Conclusions.

33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg