Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On force-field models of the spacecraft flyby anomaly   Recently, Anderson et al. published an empirical prediction formula for the
so far unexplained parts of the velocity changes of spacecrafts during Earth
flybys. In the framework of a perturbational approach, we show that there is no
velocity-independent force field of the Earth - in addition to its Newtonian
gravity field - that is to reproduce this formula. However, we give examples
for fields modeling exactly the flyby anomaly which are quadratic functions of
the velocity of the spacecraft.

31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
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The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
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The categories of this paper are: stat
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The categories of this paper are: q-fin
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
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The categories of this paper are: cmp-lg
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The categories of this paper are: nlin
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The categories of this paper are: hep-ex
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The categories of this paper are: math-ph