Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Zeno effect in atomic spin-exchange collisions   The suppression of spin-exchange relaxation in dense alkali-metal vapors
discovered in 1973 and governing modern atomic magnetometers is here
reformulated in terms of quantum measurement theory and the quantum Zeno
effect. This provides a new perspective of understanding decoherence in
spin-polarized atomic vapors.

21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg